Reid Welch
1 MW
Thanks to Tyler Durden for saving and offering a copy of this old thread from the ruined original VisforVoltage forum.
In time I'll format it into digestible chunks of several posting per form.
at present there's a lot of dross (my jokings) that I'll probably trim off later.
Start:
Posted by: Reid Oct 3 2006, 04:56 PM
This thread will detail adventures met training a 250W Unite Motor MY1018
to scream like a banshee without dying like a kamakazee.
By force-cooling of the armature (fechter taught me),
we'll uprate the motor's heat tolerance, but not it's electrical efficiency;
to allow the mite to live--as if it were a 600 to 900W motor.
No more charred windings, that's the main goal.
Secondary goal: a fast (25mph) cruiser bike which I won't have to pedal home dead after a hard ride.
Also planned: to experiment with advance of the brush timing--for better top-end power.
MY1018 weighs only 5 pounds. It bolts on, and is very easy to service.
TNC Scooters will be stocking the MY1018 24V gear motor begining this
month--Good for bottom bracket drives and rear hub drives.
ban blue smoke
Posted by: Reid Oct 3 2006, 11:06 PM
This motor is available from the maker wound for 36V, retaining the same characteristics.
Even so, I prefer the 24V version.
The 36V version will give the same performance specs. at 36V, as the
24V version does on 24V (so state the published specs--theory notwithstanding)
The Currie line of cheap ebikes, with the lone exception of the red "long range" cruiser, use the 24V Unite motor, so that's what I have to work with.
By adding another 12AH battery I got 36V and about 33% boost in torque and top speed,
both of which were exhilarating.
A gear motor has great advantage (impo) over typical BL hubmotors, (I write for newbie readers like myself now),
in that it has great torque from a standing start.
Direct drive hubmotors, except for the Giant Ampeaters,
do not do much to scoot you from a dead stop.
This tiny gearmotor overvolted to 36V whisks my 150lb self plus 85lb bike
right across a busy intersection--no need to pedal.
But... running a 24V MY1018 at full throttle for more than a few miles at a time at that higher voltage,
shoves lots more power through the armature and will char the windings pronto.
After seven miles of a motor destruct test:
__________________
Posted by: Reid Oct 3 2006, 11:19 PM
http://img395.imageshack.us/img395/2546/screenshot092is1xl6.jpg
The end result of over-baking the wire enamel.
The gray stuff is either smoke condensate, or, more likely, enamel
going to ash.
The black area over by the thumb and over at the seven o'clock area is
where the turns shorted badly.
As you see the entire thing was pretty hot--most of the visible wire
evidences heat damage.
The putty appears to be some sort of heatproof stuff for dynamic balancing.
Enamel can withstand, what? --Probably four or five hundred degrees
without appearing to burn, or make ash or smoke stains.
This motor was probably dissipating about four hundred watts of
electricity as waste heat in the armature (guesstimated).
Being sealed up a small housing, of poor thermal conductivity overall,
that much heat inevitably burns the wire--the temperature rise must be steady, and almost without limit--except that
the motor burns out, and that's it.
Short runs at high speed (overload is the same thing) will not cause
this.
A long, lugging haul of a grade on 24V will surely burn a motor like this in not too much time. Lugging puts over 750W through the motor, even at 24V.
But, the motor is nowise capable of withstanding that power level in stock form.
Cooling would prevent it all, just like that; simple.
Convective and radiant cooling is not enough here.
By forced air cooling it should be possible to avoid this from
happening to the new motor, which just arrived today.
fechter taught me how best to do this by his example.
Brushed DC motors particularly benefit from air-over cooling
Think of AC electric drills and saws and the like...they are fan cooled,
liberally-so, and handle much power, and make a lot of waste heat.
More later after system construction is in progress.
____________________________
Posted by: Commute20mile Oct 4 2006, 07:25 AM
Great posts. Keep 'em coming.
Posted by: Reid Oct 9 2006, 02:21 PM
Beginning to mod the Unite MY1018 today.
Figuring out things as I go along.
Good surprise: the housings are diecast zinc.
This means that it drills very easily and cleanly.
I won't have to remove, pry out/disturb the brush plate in order to
Swiss cheese its cover
(there's a few mm. of air gap between the inside of the cover and the
brush holding plate).
Diecast makes no curlycues of metal which could otherwise lurk and
remain under the brush plate,
to go adrift later on and cause mischief.
Pictures to be taken later today or tomorrow will make all of the steps
clear.
Swiss cheese the brush cover plate? Yes, to some extent.
This'll be the easiest way to put air into the motor.
I will recycle the old motor's brush cover plate--using it as a plenum
cover.
That is, it fits, Oreo-style, over the existing cover.
Spacers of a few mm. thickness... and a nipple for the air hose?
That'll mount in the former ball bearing's space in the recycled cover.
The finished result will look like stock, but protrude a half inch or
so more from the bike.
It will have a copper nipple press-fitted and epoxied into the center
of the cover.
I'll probably paint the whole thing with a light coat of Krylon flat
black, to further maximize radiant cooling.
The stock motor is painted silver.
The silver paint yields quickly to paint remover.
So it's bare as a baby right now.
Next step--ventilate the brush cover.
I'll also be advancing brush timing by about 7 to 10 degrees (roughly)
by re-indexing the new motor's brush plate/cover assembly.
This requires drilling just four new holes.
The old cover plate will guide my hand drill.
Pictures later, having too much fun right now.
Gee, what if this all works out?
Well, if it doesn't--if I burn up this motor too in torture testing to
come,
I'll buy a new one from TNC scooters. They should have stock of this
MY1018 very soon.
I consider it to be a consumable item (not like a BL $$ hub motor).
So, to have a spare, ready to slap on, it a good plan.
And if it doesn't burn up on 36V and flat-out running, after this
force-cooling mod?
How long will it last? I'm curious to find out.
Cheers,
Reid
----
Next posting will show pictures more or less self explanatory.
I'll caption them only as needed.
Posted by: Reid Oct 9 2006, 06:47 PM
The inside of the diecast motor cover carries the brush plate:
phenolic board standing about 3mm off from the inside surface of the
cover.
This plate has a 3mm air gap. It stands on four lugs, one of which is
noted by the white cursor.
The lugs are swedged a bit to hold the phenolic.
Removable by prying, but I didn't wish to disturb things--there is no
need to do so because the metal drills so cleanly.
http://img20.imageshack.us/img20/7898/screenshot045wr6.jpg
The cover has already been ventilated--air will pass around the
perimeter of the brush plate
and also around the center hole, hitting the commutator and brushes
with cool air.
____________________________
http://img176.imageshack.us/img176/5081/screenshot044ls4.jpg
On the right is the very same cover as above. See the phenolic board
peeking through the air holes.
Note the other cover--the gear-end cover of the motor has twelve air
exit holes.
These will be baffled to prevent ingress of water splash, no worry
about that.
____________________________
http://img242.imageshack.us/img242/2967/screenshot043xd6.jpg
Here are the major parts of the MY1018. So simple.
OK: the extra (leftover) brush end cover from the old motor is to be
used as a plenum cover;
that's it laying atop the new motor's brush plate cover.
It will get a 3/4" copper elbow fitted to its center, next step.
I will grind off its flange and attach it with self tapping screws to
the ventilated cover.
Air will be forced into the plenum, go through the holes, around the
brush plate, through the motor,
carrying off waste heat generated in the armature.
This is all done to allow the motor to live longer at high loads, high
speeds.
As a sealed motor, it gets to be like a miniature oven inside.
The modification will make it like an oven with an open door, and a fan
blowing on the turkey.
It should be less liable to roast turkey this way.
I am, of course, the turkey, if the armature...roasts!
Note how cleanly the diecast zinc drills. This was a great
troublesaver, to not have to pry out the brush plate.
Note the little gear case? That is to be packed with grease, per usual.
I will vent the case, though ,with a couple of small holes.
When a case is packed full of grease and then the gears are run,
thermal expansion plus the churning, forces excess grease out through
the "sealed" beaings
*there is no such thing, really*.
The bearing behind the output sprocket is of the metal shielded type.
It will pass excess grease readily, until the excess is relieved.
The bearing behind the drive pinion (integral with the armature) is of
the rubber "seal" type.
This type passes less grease, so relatively little grease gets into the
armature housing.
Anyway: by making two small grease holes remote from one another
I can "change" the grease in the compartment from time to time, if
thought needed,
without opening the case up.
Two small self-tapping screws will seal the holes when they aren't
needed.
Next step: mate the fake cover to the real cover and begin air flow
tests (that is, guess whether I've got a free enough passage for the
air pressure the blower will provide. If less restriction is called
for,
more holes will be drilled, no sweat.
So it goes...
fun!
Posted by: fukenfooser Oct 9 2006, 07:15 PM
"MY1018"
I'm following this with interest.
Because I just recieved my own MY1018.
Not the geared one, a different one.
"MY1018 CE
Voltage: 24VDC Rated speed: 2500 RPM
Rated current: 16.5A Output: 300W
Jx JX Motor Co.,Ltd"
Was picked up off E-bay
$.99 + S&H of $20.00
Black body, Silver end caps
about 4" Dia, and 3.4" long
Has 4 bolt mnt plate built on
Shaft= 15/32", with a .393" dbl flat sided sprocket mnt under 19/64"
threaded end
also has dbl flat spots on main larger shaft area about 3/8" across
flats
11T #25 chain size sprocket came on it.
ZERO air cooling as no holes at all
front end plate has 4 screws, rear has nothing
Spins either way with 12 VDC to wires, (cw or ccw).
When shorted, (wire held together) the motor is harder to turn.
This is a test we, (R.E. people, aka windmills ect,ect..)
do with DC motors to see if worth picking up when found in travels.
I was working on building a mini E-scooter or something like maybe
the "Sparky II".
So watching what you do to help cooling will be of interest !!!
The "Solar Scooter" I was given has gotten me bitten to have
a faster E-Ride Toy.
The ss has a motor with built in jackshaft like the newer MY1018's
have.
All belt drive, but limited speed as being a "old fart" type, 15 MPH,
but
hey, I't do wheelies if rode standing and being in turbo speed, (button
on)
when starting from dead stop just do like on a bike, pull back on
handle bars a bit
as motor starts to push it forward!
Would be great for parts if it wasn't a working E-ride.
I should just mod on it but hate to ruin it.
Still thing it would be cool chopped out.
http://www.visforvoltage.com/forums/uploads/post-22-1160435710.jpg
Attached Image
Posted by: Reid Oct 9 2006, 08:22 PM
Good! I'm glad that the general principle here is of interest to folks.
We are hot rodding mini motors.
Bearings:
The perversity of manufacturers...
The ball bearing, as a -general rule- should be a light press fit on
the shaft.
It should not be a slip-on fit or the shaft may at times spin in the
bearing's ID bore,
making wierd noises that come and go, and eventually possibly causing
shaft damage.
Unite had the bearings set up as a bare slip fit on both of the two
motors I've seen now.
A small sin in my opinion, but a sin nonetheless.
So, just as good, even better than press fit here, is to slip the
bearings back onto the armature shafts
using a locking agent. "Stud and bearing mount" is another name for
this thick red anerobic cement.
Use it sparingly--a dab'll do ya.
Now, the other side of the coin: as a -general rule- the ball bearing's
outer race should be a bare slip fit in the supporting cover's bore.
This allows for thermal expansion. IF both ID and OD of the ball
bearing are press fit-tight, there's no relief for strains engendered
when the motor heats or cools.
Shortened bearing life may result.
Radial load ball bearings like these are not meant to take much of a
thrust load.
On the other hand, the castings are thin and somewhat flexible/springy,
to a couple of thousandths of thermal growth----differential of
dimensional growth between armature shaft length and housing length.
Unite provides (correctly) a spring washer behind the brush-end ball
bearing, to keep it all lightly pressed forward, to prevent end shake
rattles that could otherwise occur
(and prevent the -wear- to the castings' bearing bores that woud
entail).
If the OD bore is worn or slopped, it -might be OK- to apply a bit of
silcone rubber type of glue.
If the parts are grease free... the silicone rubber is elastic enough
and yielding enough to allow thermal strain relief, while also
immobilizing the OD of the bearing from chattering or spinning out in
the bore (so long as the bearing runs without internal failure, ie:
grinding up. Then somthing's gonna give and you'll know it by loss of
power and terrible noises, probably.
See that Unite uses a rubber "sealed" pinion-end bearing here.
This is to better exclude gearcase grease.
However, such bearing seals are only rated to keep ball bearing grease
-in- the ball bearing.
They cannot prevent grease or oil migration shoving or leaking
-through- the bearing from an adjacent grease-packed case.
But, as noted in a prior posting, the output shaft bearing is only
metal "shielded", and so,
leaks excess grease to the outside world, in preference to the grease
going back into the motor.
So, no problemo.
If it were a critical application, an "umbrella seal" would be called
for.
Here there is no room for, nor any real need for an umbrella seal (It's
a sort of flanged rubber compression seal).
__________
Bearings cemented in place for silent running
http://img243.imageshack.us/img243/5867/screenshot046sc7.jpg
Posted by: Dom Oct 10 2006, 09:19 AM
Good stuff Reid
I must have missed a post somewhere -you finally got a proper
replacement motor??
With all your cool plans -this motor should be a rocket!!
I was surprised when i put my controller(which never felt like it got
warm ever) in my battery bag -the bike cut out after a few minutes
normal running.
Took me a while to work out it needs air running over it -even a small
amount!!
Cheers Dom
Posted by: Reid Oct 10 2006, 10:07 AM
Yeah, Currie at last sent a new motor.
I was just humbled by my ignorance again:
-motor partly assembled (sans output gear),
I ran it from a 12V battery, holding the brush cover in place.
Rotating the cover anti-motor rotation, the armature spins faster,
smoother!
Ooooo (I thought!) More power at speed!
Then I smelled smoke. Glanced at the clip leads.
Melting vinyl. I pulled off the brush cover pronto to prevent the
neighborhood from burning up.
hahahha.
Stufu just learned: advancing the brush timing much past (presumed
neutral?) factory setting,
increases no-load current draw enormously.
I will forego timing advance for now.
My fingertips are blistered! (not really)
I hate the smell of blue smoke.
Break---finish it later today.
Fume meanwhile.
Cogitate.
Grow Less Stupid
(maybe!)
--------
Currie seals the controller in an airtight cubby.
I don't know how they get away with that.
It's just above the b.b.; a totally closed box,
designed to hide the controller and...retain rain water.
cheers to Dom from me,
Mr. Dummy
Posted by: Reid Oct 10 2006, 07:27 PM
http://img353.imageshack.us/img353/6299/screenshot047hy0.jpg
http://img487.imageshack.us/img487/4360/screenshot049pl2.jpg
At this writing the brushes are running-in on a 12V feed, no load.
The plenum cover will be screwed on with sealant
and the unit painted with Krylon satin black for appearance and for
that little extra bit of cooling afforded by a thin coat of black paint
(black is a cooling color).
The 3/4" copper elbow is an interference fit. The slight protrusion
inside the cover is riveted over;
nicked with a chisel and cemented with red bearing locker.
It should hold OK. Don't want it to fall out, ever.
I've decided to mount the motor in a new orientation:
the big circle hanging down instead of up.
It'll look a little neater.
The blower will get mounted next
to the underside of the existing seatpost rack.
It is a 24V blower. The bike is 36V.
It was discussed here on forum, and determined earlier, that the
simplest way to drop 12V
for the blower is to run a 12V 1A auto lamp in series with the blower
supply.
The blower will be fed in parallel with the motor.
Therefore, its action will be entirely automatic, in sync with motor
speed/cooling needs.
The two long, protruding RH screws are temp. caps for the grease
input/output holes I just drilled into the gear case.
They'll be replaced with stubby screws. By this means I can regrease
the gear case as desired without stuffing it over-full.
It has occured to me that I -could- engineer a grease pumping
system--grease pumped by the pinion and driven gear, recirculating, and
shot out into the mesh of the pinion-to-driven gear.
That's for the next motor. This one I just want to run asap even before
installing the blower.
I'll just keep the speed down for now until the blower gets fitted,
holding my speedgreed to 17 or 18 miles per hour; it'll be OK at that
number.
Once blown? Full bore and 25 per!
Posted by: Reid Oct 10 2006, 10:38 PM
Here's a blowup of the Currie Izip cruiser motor drive
back when it was bone stock (Aug 13th)
http://img463.imageshack.us/img463/9148/screenshot052zp6.jpg
Now it's time to test the blower. "24V 10W", it cost about five bucks
from Marlin Jones electronics (thanks fechter for the lead)
The motor, even idling on 12V grows warm to the touch.
Next I lashed up the blower.
It's so quiet on 24V that I think it's wiser and better to
run it full power all of the time.
After five minutes the motor case was cool to the touch
http://img174.imageshack.us/img174/3953/screenshot053pu1.jpg
Quite a breeze is going through the motor.
The motor was stone cool after five minutes of blower operation.
The two units are running--the frash flozen motion.
How to mount the blower to the seatpost rack?
http://imageshack.ushttp://img140.imageshack.us/img140/4064/screensho...
"The thin' hay no room!" says Ren.
Never fear! I, Stimpy, have a hAcKsAW.
"You are a genius idiot"
Righty, Ren.
We are a team.
http://img183.imageshack.us/img183/1369/renandstimpytn0.jpg
"Dom will be so jealous...." (audio joke)
http://img174.imageshack.us/my.php?image=sound128ek8.swf
Posted by: goofproofpc Oct 11 2006, 12:19 AM
QUOTE
"Dom will be so jealous...." (audio joke)
http://img174.imageshack.us/my.php?image=s...sound128ek8.swf
LMAO............. Dude might want to consider seeing a
shrink.........lol
Matt
Posted by: Reid Oct 11 2006, 01:09 AM
Doktor Felix Risinggarter, consultant:
http://img142.imageshack.us/my.php?image=sound129rg1.swf
----
If Matt were here I would paint him like this (j/k)
http://img145.imageshack.us/img145/373/screenshot057zi9.jpg
for disrespect of a comedian.
Hanging? Mandatory of course.
I kid a lot.
The project should be basically finished by tomorrow night.
For the voltage dropping lamp I think I might use this 11W non-halogen
PAR lamp
already on hand:
http://img222.imageshack.us/img222/4794/screenshot058lt3.jpg
If I spritz the lens with red Krylon "Stained Glass Color" paint,
woot: what a nifty tail light. Wide flood too boot.
I -think- the blower motor will be audible enough, that I'll know it's
running.
That is, if the blower were to fail and I did not realize it (the lamp
was gonna be a tell-tale in my line of sight), I could fry the motor.
Let's see. One guess leads to another.
Matt, go have a beer and have fun.
BTW, is your sister free on Saturday?
no?
How about Wednesday?
Oh, nevermind, lol!
Posted by: Reid Oct 11 2006, 09:05 AM
OK, enough joking around; back to work:
There's not enough room on the seatpost rack.
http://img167.imageshack.us/img167/1674/screenshot063br7.jpg
The SLA battery is double-stick foam taped to the rack.
Man! It's really on there! I can't pull it off.
Why bother, anyway? It's in its best postion.
Hacksaw two sides...
http://img133.imageshack.us/img133/6008/screenshot064it8.jpg
Bend the flange and off it breaks...
http://img100.imageshack.us/img100/536/screenshot065vn4.jpg
Now there's room...
http://img218.imageshack.us/img218/4764/screenshot066cx8.jpg
The light bulb for a dropping resistor:
Did not work according to theory.
The blower's current draw is directly dependant on the load.
Since I've choked off the blower's output, it draws less current.
I found that even a .6A 12V bulb only dropped about four volts. Not
enough.
Trial with lightbulbs on hand showed that either a 150W 120V regular
bulb would work (too bulky!)
OR, that slim 100W halogen seen in the top picture.
Both give virtually identical voltage drops. Odd, eh?
It's because the relatively cold tungsten filaments have very different
resistances,
explained by the very different lamp technology between the two.
I'll use the slim halogen for a self-regulating dropping resistor.
There is -some small measure- of voltage regulation:
When tungsten is hot, like copper, its resistance increases.
This sort of application is technically called a "barreter" resistance.
Crude, but I don't have to go mess around with power resistors, etc.
The lamp only gets warm to the touch. I guess it's dissipating less
than five watts.
Where to stow it?
How about in here? Padded, of course.
It'll never break or burn out.
http://img144.imageshack.us/img144/8889/screenshot062oo3.jpg
___________
This is real-time reporting of home brew modding by a hacksaw and
solder guy.
I'm posting pictures as I progress and think it through one step at a
time.
Now I am wanting a DPDT switch so I might have the blower run either
from the motor supply (variable)
-OR- flip the switch to run full tilt.
That way I can have (or avoid) the soft turbine whoosh when the bike is
running slowly--when full cooling is not needed.
-OR- if the motor's hot I can cool it down fast, even while the bike
may be still.
I hope this is getting interesting in its humble, cheap-way manner of
style.
More later this AM
Reid
On to the blower:
http://img150.imageshack.us/img150/1541/screenshot061lp7.jpg
Posted by: Dom Oct 11 2006, 09:05 AM
QUOTE (goofproofpc @ Oct 11 2006, 12:19 AM)
QUOTE
"Dom will be so jealous...." (audio joke)
http://img174.imageshack.us/my.php?image=s...sound128ek8.swf
LMAO............. Dude might want to consider seeing a
shrink.........lol
Matt
Don't know if i went GREEN but i went pretty RED from LMAO double
time!!
You'll definately have a rocket there Reid!! Top Stuff!!
You need to have some of those wind ribbons so we can see the hot air
coming out!
Cheers Dom
Posted by: Reid Oct 11 2006, 09:22 AM
I'll hang 'em to me mouth...
http://img180.imageshack.us/img180/7492/mickymouselockwl5.jpg
mouse!
Posted by: Reid Oct 11 2006, 11:10 AM
While waiting for epoxy putty to fully harden so it may be filed:
To increase the pressure delivery of the blower
the inside of the cover, which has a uselessly wide air gap from the
cage,
is getting filleted with putty to decrease that gap.
Then I file and fit by hand and shoot for 1 mm or less of air gap.
Don't want it to scrape, but don't want to waste air.
The centrifugal principle depends on inertia of air put to great
velocity.
Curiously, but it makes sense: when we block the output of a
centrifugal fan, what happens?
-The motor unloads and speeds up greatly. It draws less current.
-But, as air delivery is progressively choked off, the pressure goes
up.
Makes sense, huh?
I want max pressure from the fan, to put max volume of air through the
restrictions of the hose, fittings and motor cooling path.
I figure to fiddle this project for these few days. It's all good.
Not sure just how much the fan-tuning really counts for. Maybe nothing.
Maybe just that little bit of extra air delivery---there can't be too
much but there could be too little.
Have to make a filter/bug excluder too.
And figure how to dress the seatpost rack over with fabric so it looks
half normal.
That leftover cover from the kiddie trailer--yellow ripstop nylon.
I can't sew but I can velcro and glue
and hacksaw and solder, lol
Posted by: Recumbenz Oct 11 2006, 12:36 PM
Reid:
This is really fascinating! The MY1018 promises to be a really
cost-effective motor for bottom drive applications so your hot-rodding
efforts are being closely followed.
Question:
Simply drilling holes as you've done will permit a certain amount of
air circulation through the motor to dissipate heat. Is it possible
that adequate ventilation could be achieved without the all the hassle
of a motor driven blower? Passive pressurization could consist of
nothing more than a forward-facing funnel directed into that copper
elbow. As soon as the bike is moving there'd be a lot more air moving
through the motor than stock.
A passive ventilation mod would be a lot easier to live with yet might
still do the job ??
Peter
Posted by: Reid Oct 11 2006, 12:45 PM
Hi Peter, best regards are offered to you for your ideas.
Yes, I thought of that too. I don't know. Somelse will take that
gamble.
Let's presume for a moment that a funnel (like old ships used) would
ram enough air in
at speed, to keep the motor cool enough.
OK, now the next scenario: Climbing a grade with the full force of 36V
jamming maybe 25 or more amps through the motor. And no headwind. Maybe
a tailwind.
I'd worry that it'd fry under adverse conditions.
I figure we must carry off up to 400W of waste heat at times.
If I don't burn this motor I'll learn in time just how long it lasts,
it being brushed and all.
Sort of a consumable thing, is how I look at it.
I would be delighted to get a thousand miles before the next motor
failure. Delighted and amazed.
Then put in a new motor---swap in a new brushplate and armature and
driven gear---that's all that wears (drive pinion being machined from
the armature shaft).
I don't think gear wear will be a problem.
I think it'll be heat strains, then commutation troubles.
Nearly ready to trial it,
cheers,
Reid
____
The motor is dry-fitted
The lamp-resistor is stuffed inside the seatpost rack's hollow tube.
The blower is mounted
The vinyl hose is getting wrapped in that sort of spiral black cable
wrap, to dress it up
The controller needs some sorting out of its wiring connections (TNC
controller giving me fits)
Hook the blower wires to the main battery supply (for now it'll be just
that one way).
Need to pump grease into the gearcase of the 1018,
install the grease retaining screws
and go for a ride.
Posted by: Buzzz Oct 11 2006, 01:13 PM
" Dom will be so jealous " lol... oh my god Reid.. you have just
surpassed any level of weirdness i have ever seen before !!!! top job !
lol... oh god.. my ribs hurt !
Posted by: Reid Oct 11 2006, 02:42 PM
I'm just being a funnyman. Not weird and not mental.
Some people, I swear! Like, so--I like pancakes. That's normal enough,
right?
Right??? OK. So I like pancakes.
I have trunks full of them.
_______________________________________________
Here's the general look at the moment
http://img196.imageshack.us/img196/7021/screenshot068yd9.jpg
I cannot get the TNC 36V controller to behave properly;
can't figure out why the throttle does not work correctly..
So I'll reinstall the Currie's stock 24V controller which worked
flawlessly on 36V.
Have to solder five little wires back together. Oh bother.
So while I break from tedium I just took these pictures.
It is a nice day in Miami. About 75F and partly cloudy, low humidity.
This is the beginning of our six months per year of about the best
weather in the USA.
Don't move here though. It's too crowded.
And no one speaks Henglish hanymore. Only Cockney. But that's only me,
joking again.
Pardon if I log off? I am hungry.
Pancakes, you know...
lol, but oww, I am tired of messing with the incompatible 36V
controller.
Into the bit bucket for it.
Just a few more connections and
http://img383.imageshack.us/img383/8241/screenshot069qn0.jpg
Captain! Didja see 'er? A great blue whale! Look!
THAR SHE BLOWWWWWS
*am looking now with imagesearch for a woodcut of Ishmael, the narrator
of Melville's "Moby Dick".
Will post the first image I find of "Ishmael".
OK.
Posted by: Reid Oct 11 2006, 02:47 PM
no one should ever not not hijack any thread of mine which I didn't
start in the first place.
clear enough?
Imagine him as a whaling sailor?
Captain! Didja see 'er? A great blue whale! Look!
THAR SHE BLOWWWWWS
http://img96.imageshack.us/img96/4651/ishmaelzm3.jpg
"Ishmael" is his name, it really is.
Forget whaling. Imagine him on one of Steve's monkeyshine bikes
---
Back to reality and the $*#*%*# controller issues...
PS: "thar she blows"
http://img279.imageshack.us/img279/4237/screenshot070ue7.jpg
get it now?
not funny?
well! you should try comedy sometime, mr. whoever you are who's running
up the read counter.
FIVE people are following this thread; no more than that. Who's running
up the read counter?
I'd like to know.
Lessee: there's me and Dom and Buzz and a couple others and then
there's me and me and me me and me and me me and me and me me and me
and me me and me and me me and me and me me and me and me me and me and
me me and me and me me and me and me me and me and me me and me and me
me and me and me me and me and me me and me and me me and me and me me
and me and me me and me and me me and me and me me and me and me me and
me and me me and me and me me and me and me me and me and me me and me
and me me and me and me me and me and me me and me and me me and me and
me me and me and me me and me and me me and me and me me and me and me
me and me and me me and me and me me and me and me me and me and me,
etc.
So I guess it's all my fault. Usually is!
I love to laugh and make people happy.
I love to laugh and if people don't like it?
(I cannot speak that language here)
g'day
Posted by: Reid Oct 11 2006, 04:55 PM
Before the rebuild this motor was notably noisier than the original
that came with the bike.
I just filled the gear case with Valvoline synthetic bearing grease.
One shot seems to be enough.
http://img516.imageshack.us/img516/8485/screenshot071db8.jpg
The motor had run for ten hours last night, unloaded, at low speed.
The shafts now have their bearing cemented to them
The bearing seats in the castings were given a smear of a synthetic,
rubber glue (oil and grease proof stuff). So I know nothing is spinning
or working in bores or on shafts.
The Currie controller has just been reinstalled. It works great.
This motor is positively quieter than its predecessor.
It makes but a fraction of the whine that it made a few days ago before
the teardown.
The bike runs -great-.
But yeah, the motor still makes a lot of waste heat.
After a two mile full throttle run the case temp. was 135F.
This is surely cooler than it would've been without the modest flow of
cool air blown through.
The blower is wired to the main battery. I left it running after
parking the bike.
The motor was exhaling hot air, as expected.
But it cooled down quite quickly--in five minutes or so.
I do not know yet whether the blower delivers -enough- air to ensure
the motor's survival at full, 36V throttle.
I don't want to risk burning this armature too, not until I get a spare
MY1018 from TNC scooters.
Once I have my spare? Time for another destruct test.
And -if- the armature burns up, I'll make another blower system. Forced
air---even positive displacement, such as a bellows is not out of the
question. A piston pump would be noisier.
This blower, though, makes a great TURBINE sound. It's sort of cool.
Summary to wind this up for now:
The motor does run cooler.
The blower cools it down.
The motor runs very much quieter than before.
The predominant whine seems as if it comes from the controller.
Do controllers whine? I suppose it's just transmission of noise from
the gear to the b.b.
Its a very speedy bike for what it is.
It feels solid as a rock and it is a happy bike once again.
So am I!
(happy, I mean. I am not a bike)
Posted by: jondoh Oct 11 2006, 05:36 PM
135 deg F is around 57 deg C which is in the somewhat safe range for
most electronics. Still a little warm-- but not warm enough to bake
cookies.
I have to think that even that heat will shorten the life of the motor
compared to larger motor or the same motor run at lower power. Maybe a
year or two depending on how often it's run. It would be nice to find
out. Keep up the good work!
Posted by: Reid Oct 11 2006, 05:56 PM
Yessir, I agree: overstressing a modest motor like this one will vastly
shorten its life.
Although the outside case temp. was 135F, it would have gotten hotter,
I think, had I run longer.
And does the outside case temp really -tell what the armature and
brushes and commutator are feeling?
I suppose the windings are much, much hotter.
At what temperature does modern wire enamel begin to char? Hmmm... 500F
perhaps?
I need to find that out.
If I had taken more time I'd have installed a temperature probe
to monitor the core of the motor housing: say, poking in between a pair
of the magnets.
Still, I can't say what the armature temp is running until
a) it fries and b) I learn what is the destruct temperature of enamel.
After all, the main place of heat production is in the commutator and
in the windings.
Good thoughts--thank you for helping me along.
The point of this exercise is to see if a cheap motor can live along
hostile terms,
and for how long. Seven miles is it for the stock motor.
We'll see... now if my "improvements" were worth the doing.
cheers,
Reid
Posted by: Nickf Oct 11 2006, 05:59 PM
Great thread Reid,
Nice to see all the photo's, I can see this developing into a a
trend....
I think maybe your new motor might work better with the blower. When I
fried my brushed motor it never worked the same and generated a lot
more heat. I've heard other saying the same thing - that no matter what
they do they never quite get the same performance. Maybe the heat and
current combo damage the magnets?
Posted by: csaudio Oct 11 2006, 08:12 PM
Reid
Controllers whine. If your ears are really good you will hear more of
it. The switching frequency of most controllers is less than 20kHz.
You can think of your controller housing as a tweeter.
Hub motors also whine for the same reasons. High freq switched signal
in to the motor turns it into a tweeter.
csaudio
Posted by: Buzzz Oct 11 2006, 08:31 PM
What are the effects of higher or lower frequency controllers ?
efficiency ? sound ? performance ?
Posted by: Reid Oct 11 2006, 08:36 PM
Hi Nick,
Please tell us about the circumstances that led to your damaged motor?
I've read that even one shorted turn will spoil a motor's performance.
As for heat damage to neodymium magnets? They are not the best for heat
resistance.
The four neodymium magnets of the Unite motor are, I suppose, mounted
the same way in all modern motors?: the core of the structure is an
iron or steel band, to which the magnets are cemented? or otherwise
fastened. The band is cast into the zinc housing of the motor.
If magnets weaken, yeah, the motor will weaken. But a shorted turn is
more likely (I think)
>From Wikipedia's entry on the subject:
QUOTE
A neodymium magnet or NIB magnet (also, but less specifically, called a
rare-earth magnet) is a powerful magnet made of a combination of
neodymium, iron, and boron - Nd2Fe14B. They have replaced marginally
weaker and significantly more heat-resistant samarium-cobalt magnets in
most applications, due mainly to their lower cost. These magnets are
very strong in comparison to their mass, but are also mechanically
fragile and the most powerful grades lose their magnetism at
temperatures above 80 degrees Celsius High temperature grades will
operate at up to 200 and even 230 °C but their strength is only
marginally greater than that of samarium-cobalt. Neodymium magnets (or
"neo" as they are known in the industry) are graded in strength
from N24 to the strongest N54. The number after the N represents the
magnetic energy product, in megagauss-oersteds (MGOe) (1 MG·Oe = 7,957
T·A/m = 7,957 J/m³). N48 has a remnant static magnetic field of 1.38
teslas and an H (magnetic field intensity) of 13,000 oersteds (1.0
MA/m). By volume one requires about 18 times as much ceramic magnet
material for the equivalent magnet strength. The neodymium magnet
industry is continually working to push the maximum energy product
(strength) closer to the theoretical maximum of 64 MGOe. Scientists are
also working hard to improve the maximum operating temperature for any
given strength.
Note that there are many grades. Inferred: the weaker grades are less
liable to heat damage.
__________
Henry's Model T generated its lighting and ignition current supply by
flywheel magneto.
The best magnetic then was glass-hard tungsten steel. Many were the T
magnetos
I'd remagnetize, using the coil sheet of series-wound bobbins, against
which it worked,
to produce the required magnetic field.
http://img133.imageshack.us/img133/1411/screenshot072te0.jpg
If a T overheated badly, the magnets often lost their mojo. Weak
ignition resulted.
The system generated AC current. In time, normal engine temperatures
and vibration weakened these magnets. However, they can always be
recharged.
I wonder (don't have a clue) how they put the magnetism into our
manufactured "nib" magnets?
Early radio speakers had U shaped hard steel magnets. By winding turns
of enameled wire around
an age-weakened magnet, and then goosing it with a fully charged
-large- capacitor of hundreds of volts potential, I found it easy to
restore the magnet--in a flash, literally. I'd always fuse the wire in
doing this trick. That quick -break- of the magnetic field is what
kicked the magnet to fully saturate.
I digress.
______
The bike battery is charging. Perhaps later tonight I'll go out and
make runs up and down a smooth, residential boulevard nearby. With the
Raytek IR thermometer, I'll check the motor housing temp at half mile
or so intervals. At full throttle, the temp is bound to rise---to some
point yet to be learned.
I just don't want to kill the little bugger quite yet.
Thanks for positive reactions to this mixed bag-of-a-thread.
I'm glad no one's complained of the "entertainment" aspects!
That'd be such a shame if they did. See,
I'd have ta go kill'm.
(jk!)
Posted by: Reid Oct 11 2006, 08:54 PM
QUOTE (csaudio @ Oct 11 2006, 08:12 PM)
Reid
Controllers whine. If your ears are really good you will hear more of
it. The switching frequency of most controllers is less than 20kHz.
You can think of your controller housing as a tweeter.
Hub motors also whine for the same reasons. High freq switched signal
in to the motor turns it into a tweeter.
csaudio
Understood and agreed, but no, this isn't that sort of high pitched
stuff.
I wouldn't hear above 10k anyway.
This sounds like the old motor whine I know so well from the Currie,
only now it
-seems- to be coming from the cubby where the controller resides,
instead of from the motor.
It's probably due to my having repositioned the motor: it hangs -down-
insead of aiming upwardly.
(see picture previous page). Just such a move as this, plus the
prop-supporting screw I've set to
prevent the heavy mass of the motor from vibrating--these things have
changed the acoustic of the bike frame.
It may account for why the motor is so much quieter.
More likely it's a combination of things.
I've heard odd whizzes and buzzes from the two Unite motors in the
past:
due to bearings squizzing in their cups bearing ID's slipping
intermittantly on the shafts.
Now with everything "right" there's nothing to make odd sounds.
Also, I paid attention to gear mesh in setting the two end plates.
There's a small amount of radial slop movement in the die castings.
I ran the motor on 12V, moving the plates a bit this way and that until
it was quietest
then cinched the screws and applied wicking grade locktite to the joint
to exclude water ingress.
Water will find its way into ungasketed joints.
Thanks for helping guy,
Reid
Posted by: Dart Man Oct 11 2006, 10:32 PM
This thread was very entertaining. Thanks for the laughs Reid. Did you
ever get your new V-brakes to work better?
Posted by: Reid Oct 12 2006, 05:19 AM
I got the rear brake (still all-stock) working better by following your
cue and scrubbing down the brake pads. They were glazing with rim
metal. The pads grip and are OK.
Front brakes: am awaiting delivery of a Bike Nashbar brake booster
(fork truss).
This'll make my front brake lever twice as stiff. The springer fork
really springs and twists badly at present
-----
Current local weather condition report. Why?
http://imageshack.us
An hour ago I took the bike to the local high school one mile away
(four AM local time).
The quarter mile running track... (idea from Paul and Scott).
Took along the Raytec thermometer.
motor case temperature, start of the track run: 98F
Cyclometer says:
3.46 miles
23.1 average speed
24.6 max speed.
9:04 elapsed time.
temperature at the finish of the track run: 108F
Summary: under these conditions I'm sure the motor would be just fine.
The commutation in damp air must be ideal
(graphite brushes need moisture to make good commutator film).
Am surprised the temp. rise was so little.
A dissimilar (less stressful) run yesterday afternoon took the motor
case up to 135F in less time.
Perhaps it is the cooler, damper night. Perhaps also that it was an
uninterrupted run?
The motor cooling goal may well achieved.
More runs, more data.
I need a Drain Brain.
Posted by: Reid Oct 12 2006, 05:34 AM
Musing aloud:
It is well known that graphite becomes abrasive if moisture is entirely
absent.
Brushed motors cannot be operated in outer space for this reason.
Now, if a bike motor is brushed, and if that motor is essentially
sealed (as they all are in stock form),
and if the motor is run, it gets hot in there. Heat drives out moisture
from the case.
The brushes go bone dry. Brush friction (and wear) increase.
Commutator filming (a continuous, constant process) suffers.
Electrical resistance heat increases. The commutator grows hotter.
The motor efficiency falls, owing to imperfect commutation.
----Now flip the coin:
The motor, ventilated and run in cool, damp night air:
All the bad things above are reversed. Low brush friction, high
commutation efficiency.
Low motor temperature rise.
Summary:
In the track run report above this posting there's enough data to make
this hypothesis plausible.
Point in formation:
A fully sealed brushed motor is a bad propostion, period.
For it will drive out water vapor as it heats, decreasing commutation
quality.
If I lived in a desert region and ran this bike in great dryness,
I'd make a trial comparing dry air running, against humidified air fed
into the motor.
By expedient of a simple evaporative pad above the blower intake
water vapor can be added to the motor's environment.
Posted by: Reid Oct 12 2006, 08:05 AM
I've posted a link to this page, and a synopis over at the Maintenance
Forums.
There are real electrical pros there. Perhaps one of them will add to
our knowlege.
If so, I'l trans-post the information here.
Beginnning to study wire enamels.
>From the earliest days (my 1887 C&C motor is one witness), the armature
wire required to be wound in slender cotton, or preferably, silk
thread. The armature was then dipped in a varnish or shellac.
This general sort of insulation was nearly standard up to about 1920 or
so, by which time phenolic resin baking varnishes had been developed.
I've a Violano Virtuoso of 1926 vintage. Its motors are all enamel
wired, no cotton or silk. The earlier Violanos, going back to 1912 were
similarly done. The makers of that machine were doing state of the art
motor winding with top quality materials. The survival rate of these
orgininal magnetic windings today is on the order of 99 percent---they
are that well done.
-----From the war years, great advances in wire enamel. Here...
QUOTE
http://www.chemcases.com/silicon/sil10one.htm
10. Small, Efficient Motors
Silicone materials exhibit unique properties based on their chemical
structure.
But those properties turned out to be less than ideal for insulation.
In less than sixty years, manufacturing grew to more than 1 billion kg
of silicone resins made by Rochow's process.
But only a small fraction, about 10%, of that production ended up in
the small, efficient motors. Silicone polymers failed to have the
properties suitable for widespread insulation uses.
The biggest issue for efficient motors was the insulation for magnet
wire;
the copper wire windings that wrap the rotating electromagnetic coils.
The rotating coils in a generator produce the current that can be sent
to motors.
In a motor, the process is reversed and the current causes the rotor to
rotate and produce work.
General Electric's engineers could develop a long list of ideal
properties for the magnet wire insulation.
They called this insulation 'wire enamel'.
Their ideal wire enamel should have as many of the following properties
as possible:
http://img101.imageshack.us/img101/7826/screenshot074mp9.jpg
At least two dozen factors needed consideration. Some were more
important than others.
In a wire enamel, resistance to the UV rays of the sun would be less
likely to cause a problem than,
let's say, low resistance to electrical current flow.
Before the fact, before Eugene Rochow had his magical laboratory day in
1940,
no one could predict the inventory of properties that silicone might
have.
But with silicones in hand, GE's scientists and engineers sensed
trouble:
they could make silicone resins and impregnate them into glass tape
with excellent overall properties. But wire enamels made from
silicones gave real problems. Wire enamels had the required heat
resistance, but they were soft, not hard.
The enamels were easily cut by adjacent wire. Silicones were porous to
gases and water.
Many of these poor properties were unexpected and sent the scientists
in two directions.
First to understand, if they could, why the silicones failed and to
try to improve those properties. Secondly, the scientists renewed
their quest for other compositions that would work
as wire enamels.
GE's first approach to try to fix the silicones did not work very well.
Their scientists became aware of a Canadian research development, a
resin called polyvinyl formal.
GE licensed the Canadian development. It certainly was not GE's first
choice to use technology
developed by others; what was more important, was finding the best wire
enamel.
This material met the test of the broad range of properties, and by the
early 1940's
this resin, now called Formvar® by GE, became the magnet wire enamel
of choice.
The one property that Formvar® did not have was the extremely high
heat resistance of the silicones.
It was only a Class F, 150 degrees Celsius insulation, not the Class H,
180 degree
insulation that silicones could achieve, in theory.
But the enamel applied so easily, performed so well and could be coated
in such thin layers
that smaller, more efficient motors and generators came forward.
>From the beginning, GE scientists saw that silicones would have
thousands of uses beyond electrical insulation.
They succeeded in opening up many opportunities. Scientists from
around the world began to look
at other polymers that would show the complex sets properties required
for our modern world.
Chemists and engineers developed marvelously improved materials.
Posted by: csaudio Oct 12 2006, 09:21 AM
Hi Buzzz
Higher switching frequencies yield higher efficiencies as well as
allowing less iron to be used in the inductors in power leg of the
circuit.
At higher freq the FETs switch quicker and can operate more safely at
high power compared to low freq switchers.
It costs more to make the driver circuits so the cheap controllers will
have lower frequency switchers.
In an airplane the AC power is produced and distributed at 400 +Hz in
order to reduce the needed iron weight.
csaudio
Posted by: fechter Oct 12 2006, 10:25 AM
There's always an optimum switching frequency. If the motor is big and
has lots of iron, the core losses will increase at a higher switching
frequency. Switching losses in the FETs also increase. You just want to
make sure the frequency is high enough so the flux doesn't have enough
time to completely build or saturate.
Interesting about moisture and motor brushes. I never knew that. I
guess that helps explain why the brushes in my Zappy motor look
practically new after 400 miles despite being run at over 4X the design
power.
Posted by: Reid Oct 12 2006, 11:13 AM
QUOTE
There's always an optimum switching frequency. If the motor is big and
has lots of iron, the core losses will increase at a higher switching
frequency. Switching losses in the FETs also increase. You just want to
make sure the frequency is high enough so the flux doesn't have enough
time to completely build or saturate.[/COLOR
This explains to me why the TNC 40A 36V scooter controller groaned my
bike at low throttle openings.
I had relatively little bottom-end torque. So, it was not a defective
controller. It was my defective crossover application of a big-motor
scoot controller to a small gearmotor.
QUOTE
Interesting about moisture and motor brushes. I never knew that. I
guess that helps explain why the brushes in my Zappy motor look
practically new after 400 miles despite being run at over 4X the design
power.
If it turns out to be true (a 'discovery') that great excess of
humidity actually aids commutation, great!
I should be able to do some rough-and-ready tests to "prove" the
hypothesis further:
If, on a dry day, the motor runs hotter--I can dampen the blower's
airstream by wetting the filter foam. Continue running just the same.
If motor temp begins to drop: proof that more than a mere trace of
water is wanted for best commutation. AND proof that a totally enclosed
brushed motor is a bad, bad proposition.
IF that's so *not likely to bear out in testing, alas*, we will have
taught the world of totally enclosed brushmotor makers
a valuable lesson.
Perhaps Howard Penrose at the Maintenance forum will have a direct
answer to this...
burning question.
NB: do not take out-loud thoughts too seriously;
although I -think- I see a solid trend/effect,
more testing is needed.
Rhetorical question: what is the available water vapor in a closed
brushmotor at, say, 100C operating in Arizona on a summer day? Not
much! Not like my COOL motor saw this AM on the quarter mile track.
Damp morning air; I never liked the feeling of damp so much as I do
today.
____________photo by fechter:
http://img156.imageshack.us/img156/3286/fechtersb1.jpg
This is fechter's cooling job from which I drew my plans.
Note that it is surely superior in air delivery
on account of larger, shorter hose,
and probably having more pass-through holes in the motor.
Yet his is a smaller blower by far.
Posted by: Reid Oct 12 2006, 02:57 PM
it's a rainy day
http://imageshack.us
Despite the noise factor of motors with spur gearing
I've come to like the Currie system for its neatness.
The extra freewheel--the left side freewheel of the special Currie rear
hub is silent running.
It does not click click click like the conventional freewheel on the
other side of this same hub.
Why is that? Say,
wouldn't it be nice to have a world of silent pedal bikes?
All bicycles I know click click click when the rider coasts.
http://img149.imageshack.us/img149/4227/screenshot076dm4.jpg
...have yet to shroud the air exit holes.
a rainy day perspective...
thanks for having a good day
despite personal difficulties we all live with;
very small troubles they surely are
for we who have time to play with our toys
Posted by: Deafscooter Oct 12 2006, 03:43 PM
Deafscooter have many Small Blower to cool the motor it much powerful
flow like hairdryer gun
It has fully ballbeaing on motor and heavyduty brush for long life time
and it run on 24 volts DC
the nozzle dia is Exact 7/8 Inches the Centrifugal is turbine 3 inches
Rotor, house is 4.5 inches
are you intertesting to buy the Centrifugal fan for your need to
project or need to cool the motor.
For asking price each on Fan --- Call ==>> Deafscoo...@yahoo.com
Thank for Visit this Picture .........
Here is Picture of 24 volts Centrifugal Blow Fan => You measure theFan
on Yellow Ruler as size
http://www.visforvoltage.com/forums/uploads/post-22-1160682205.jpg
Attached Image
Posted by: Reid Oct 12 2006, 04:49 PM
Well, we can always count on Craig for free enterprise!
Sell me one for review/promotion purposes...
...for free?
I see it's ancient, high quality N.O.S. Xerox copy machine stuff.
This'd be a fine blower for my bike;
retro rules.
What is the static pressure produced, Craig?
Can you do a U-tube manometer test, please?
Please determine the no-flow pressure, expressed in inches of water
lift, at 24V.
It's very simple:
http://www.dwyer-inst.com/htdocs/pressure/ManometerIntroduction.cfm
use any gauge of vinyl tubing, tacked to a board with ruled markings.
http://img517.imageshack.us/img517/2972/manometerintro1picte5.gif
If it is better than my blower (which I have not so-tested yet),
I would like to try one of your blowers.
Let me know here, in public, OK?
What is your selling price?
Thank you,
Reid
Posted by: Reid Oct 12 2006, 05:05 PM
A reader sent me an email through the Voltage forum's system.
Not sure how to reply to that...whether it would go to him or bounce
back
from the V system only. It is a question of wide interest to owners of
the old
Currie add-on system.
QUOTE
hi there i have an old black 24v curry. going to give it 36v soon. any
tips. did u have black one first or something else? thanks Michael
London
No, I have had only one Currie bike and it is of the current crop,
similar in the basic drive (motor hangs off the rear hub).
Otherwise, the only similarity is the reported fact that you'll fry its
motor
if you run it hard on 36V.
Am sure you can run it on 36V if you force cool the motor.
I think it'd be much easier to cool a brushless motor than a brushed
motor.
Too bad we have not yet figured a way to cool hub motors by air draft,
not without opening it to the elements.
"We" means VisForVoltage members.
This is a team effort after all.
Cheers,
Reid
Posted by: Buzzz Oct 12 2006, 05:19 PM
Don't really need to force cool just about any brushless hub motor i've
heard about as overheating them is just about impossible without insane
measures imposed.... ie: 100v x 40 amps x Time.... I manage to get mine
warm to the touch / slightly hot at 1000w + constant ( off-road does
this !! )
Posted by: Reid Oct 12 2006, 06:06 PM
Ah, but small hub motors have reportedly burned up if overstressed.
You're speaking of super duty hub motors, aren't you?
I mean, there are more anemic hub motors out there than husky ones.
___________________
Allow, please, a few minutes for human interest digression, non
fiction,
because this biking activity leads to our meeting people:
Just last night, on the return home from testing the bike at the H.S.
track,
passing the Amoco gas station,
"Hey!"
It was Harris hailing.
Harris (not his real name) is a 46 year old black man, self-admittedly
drug addicted.
He has only a shambling old bicycle to his name. I met Harris last week
when he politely asked, outside the conveniece store across the street,
whether
I might have any spare change. We chatted. "I'm so broke. I just had to
put new
wheels on the bike. The bearings were all falling out."
He's gentle and resigned.
This AM he mentions that he needs brake pads for the bike.
"I'll give you a take-off set from mine.
But since I don't see you regularly, how can I get them to you,
Harris?"
"Well, there's a spot over behind the Dumpster behind the store."
I followed him over there to the Dumpster.
"You could put them in that hole in the broken wall. I'll find them."
While we were there he opened the Dumpster.
I am holding the lid up now while Harris inspects.
He's got his hands in the garbage.
"Man, how can you do that?"
"That's what soap and water are for."
Harris is clean. He lives nearby with his aged parents.
"It's amazing the stuff people throw away.
Just the other day I got a TV and a VCR player and they worked.
I found a six pack of El Presidente beer. One time I found one of those
inflatable dolls---you know what I mean?"
"Yes, I've seen ads..."
" I traded that to the Panamanian clerk inside the store
for some food and stuff. And so that was a good deal. People waste so
much."
Harris is no philosopher. He's a poor guy lucky enough to have parents
who keep him under roof. He gets a few bucks and does his thing.
He doesn't harm anyone. His eyes are sad.
"My stomach hurts today. I have an ulcer. Do you have any cigarettes to
spare?"
I had no money on me at all. I had no cigarettes either. He asked for
no money.
He was delighted that I have unneeded brake pads.
"I guess I'd better ride on over to the other gas station now."
I joked (I thought): "Don't ride too fast, Harris" (my bike--with an
electric motor)
"No, I can't ride fast anymore at all." he replied without any trace of
irony.
Good night, Harris.
"Good bye"
__________________
----One hundred years ago Harris had a counterpart.
What follows is a poem that I'll read to you folks,
then its back to shallower topics
such as my selfish personal interest in ebikes.
__________________
A Vanished Calling
very slowly
recited by author/me
http://tinyurl.com/s35o3
A rag man re-
arranged his shuffle
-must look smarter
for rich Mrs. Doudy.
"Any rags today kindly Mizz Doudy?"
"My oldest silks
are too fine
for you."
"Thank you 'for you'
thank you Mizz Doudy."
A rag man re-
arranged his shuffle-
no one to-day adds cloth to his duffle.
He turned to rundown
lackaday lane-where no flowers
grow where a rag man has lain
long under stars-
stirred only by sweeps-
his fibers are rag pa-
per faintly inked
-it is here that he
weeps over all
and forever.
Posted by: Dart Man Oct 12 2006, 06:08 PM
Hey Buzzz, what was the outside temperature though, don't you live up
by the north pole?
Don't you get snow?
Posted by: Reid Oct 12 2006, 06:21 PM
Yeah! BUZZZZ, (Mr. Freeze)
we want to know...
ambient temperatures count for something, ha hahhhh!
Frostbite at the least.
Posted by: Nickf Oct 12 2006, 06:59 PM
Reid,
36 volts in a standard brushless currie motors is, as far as i know, a
very bad idea. The controller is inside the motor so it may be damaged
by heat, also the fets are, so I'm told, only rated for 30v.
Peeps run at 36 volts by using an external controller with a specailly
rewired currie motor. I was lucky enough to have someone make one for
me, but they can also be brought from http://powerpackmotors.com/
I think it might be cheaper to do it your way. how much is the unite
motor? and will it fit into the old USPD (spoke clip on) drive?
Good to know about the temp that neo magnets degrade I'll have to be
careful of temperature. Knoxie had a cut out at 48 volts and thats what
i'll be running at soon, with a bit of luck.
Very sad poem, but well read. You can tell its real poverty when people
are really happy to get stuff like used brake pads!
Funny just been watching a vid thats kinda related,
http://video.google.co.uk/videoplay?docid=7875774574550696048&q=rober...
Posted by: Buzzz Oct 13 2006, 09:58 AM
Lol... you guys crack me up.....
Yes.. we get winters and snow and - 40 celcius around these parts.. but
during these 3 or so months .. i park my bike and battery pack inside
my cozy igloo !!
Summer months are quite hot.. ( well .. i would call it hot.. some of
you would laugh at the idea of 30 celcius i guess. hehe ) but during
peak summer, i've used and abused both my WE and my c-lyte hubs and
have not yet gotten a controller cut-out or motor failure or even got
close to burning my hand on my motor..
I guess if you rode in the desert up hills full throttle with the
brakes on.. yeah.. you would probably need forced air cooling somehow..
Posted by: csaudio Oct 13 2006, 01:53 PM
Buzzz
I burned up two of the Crave Chopper brushless rear hub motors. They
are advertised as 24v 450w. The first one burned up at 36v. The second
one burned up at 48v. You might think I would have learned with the
fist one, but no, sure didn't.
Neither one smoked, just gave up with a whimper.
Posted by: Reid Oct 13 2006, 06:23 PM
Same as with the first Unite! There was neither smell nor smoke, it
being sealed.
It whimpered (perfect word!) to a final stop.
______________
Buzzz as a young WC Fields:
http://img521.imageshack.us/img521/9817/fields10nh2.jpg
Reminds me (funny) of a W.C. Fields movie.
Fields, in a Yukon cabin, opens the door to survey the great white howl
outside.
Dramatically, with stage histrionics, gravely intoned for comic effect:
"T'ain't a fit night out for man nor beast."
Pause. Then he gets a face full of stage snow.
Subsequently, through the film, every time Fields opens the door again,
(dramatically)
"T'aint a fit night out for man nor beast."
Again, an absurd pause.
Fields gets whalloped with obviously fake snow.
__________
Buzzz as Fields, or is it Fields as Buzzz?
up to date and in context
"T'aint no way a hub motor burns"
Pause. A racing bike plumes dense blue smoke.
________________
Fondly kidding,
r.
In time I'll format it into digestible chunks of several posting per form.
at present there's a lot of dross (my jokings) that I'll probably trim off later.
Start:
Posted by: Reid Oct 3 2006, 04:56 PM
This thread will detail adventures met training a 250W Unite Motor MY1018
to scream like a banshee without dying like a kamakazee.
By force-cooling of the armature (fechter taught me),
we'll uprate the motor's heat tolerance, but not it's electrical efficiency;
to allow the mite to live--as if it were a 600 to 900W motor.
No more charred windings, that's the main goal.
Secondary goal: a fast (25mph) cruiser bike which I won't have to pedal home dead after a hard ride.
Also planned: to experiment with advance of the brush timing--for better top-end power.
MY1018 weighs only 5 pounds. It bolts on, and is very easy to service.
TNC Scooters will be stocking the MY1018 24V gear motor begining this
month--Good for bottom bracket drives and rear hub drives.
ban blue smoke
Posted by: Reid Oct 3 2006, 11:06 PM
This motor is available from the maker wound for 36V, retaining the same characteristics.
Even so, I prefer the 24V version.
The 36V version will give the same performance specs. at 36V, as the
24V version does on 24V (so state the published specs--theory notwithstanding)
The Currie line of cheap ebikes, with the lone exception of the red "long range" cruiser, use the 24V Unite motor, so that's what I have to work with.
By adding another 12AH battery I got 36V and about 33% boost in torque and top speed,
both of which were exhilarating.
A gear motor has great advantage (impo) over typical BL hubmotors, (I write for newbie readers like myself now),
in that it has great torque from a standing start.
Direct drive hubmotors, except for the Giant Ampeaters,
do not do much to scoot you from a dead stop.
This tiny gearmotor overvolted to 36V whisks my 150lb self plus 85lb bike
right across a busy intersection--no need to pedal.
But... running a 24V MY1018 at full throttle for more than a few miles at a time at that higher voltage,
shoves lots more power through the armature and will char the windings pronto.
After seven miles of a motor destruct test:
__________________
Posted by: Reid Oct 3 2006, 11:19 PM
http://img395.imageshack.us/img395/2546/screenshot092is1xl6.jpg
The end result of over-baking the wire enamel.
The gray stuff is either smoke condensate, or, more likely, enamel
going to ash.
The black area over by the thumb and over at the seven o'clock area is
where the turns shorted badly.
As you see the entire thing was pretty hot--most of the visible wire
evidences heat damage.
The putty appears to be some sort of heatproof stuff for dynamic balancing.
Enamel can withstand, what? --Probably four or five hundred degrees
without appearing to burn, or make ash or smoke stains.
This motor was probably dissipating about four hundred watts of
electricity as waste heat in the armature (guesstimated).
Being sealed up a small housing, of poor thermal conductivity overall,
that much heat inevitably burns the wire--the temperature rise must be steady, and almost without limit--except that
the motor burns out, and that's it.
Short runs at high speed (overload is the same thing) will not cause
this.
A long, lugging haul of a grade on 24V will surely burn a motor like this in not too much time. Lugging puts over 750W through the motor, even at 24V.
But, the motor is nowise capable of withstanding that power level in stock form.
Cooling would prevent it all, just like that; simple.
Convective and radiant cooling is not enough here.
By forced air cooling it should be possible to avoid this from
happening to the new motor, which just arrived today.
fechter taught me how best to do this by his example.
Brushed DC motors particularly benefit from air-over cooling
Think of AC electric drills and saws and the like...they are fan cooled,
liberally-so, and handle much power, and make a lot of waste heat.
More later after system construction is in progress.
____________________________
Posted by: Commute20mile Oct 4 2006, 07:25 AM
Great posts. Keep 'em coming.
Posted by: Reid Oct 9 2006, 02:21 PM
Beginning to mod the Unite MY1018 today.
Figuring out things as I go along.
Good surprise: the housings are diecast zinc.
This means that it drills very easily and cleanly.
I won't have to remove, pry out/disturb the brush plate in order to
Swiss cheese its cover
(there's a few mm. of air gap between the inside of the cover and the
brush holding plate).
Diecast makes no curlycues of metal which could otherwise lurk and
remain under the brush plate,
to go adrift later on and cause mischief.
Pictures to be taken later today or tomorrow will make all of the steps
clear.
Swiss cheese the brush cover plate? Yes, to some extent.
This'll be the easiest way to put air into the motor.
I will recycle the old motor's brush cover plate--using it as a plenum
cover.
That is, it fits, Oreo-style, over the existing cover.
Spacers of a few mm. thickness... and a nipple for the air hose?
That'll mount in the former ball bearing's space in the recycled cover.
The finished result will look like stock, but protrude a half inch or
so more from the bike.
It will have a copper nipple press-fitted and epoxied into the center
of the cover.
I'll probably paint the whole thing with a light coat of Krylon flat
black, to further maximize radiant cooling.
The stock motor is painted silver.
The silver paint yields quickly to paint remover.
So it's bare as a baby right now.
Next step--ventilate the brush cover.
I'll also be advancing brush timing by about 7 to 10 degrees (roughly)
by re-indexing the new motor's brush plate/cover assembly.
This requires drilling just four new holes.
The old cover plate will guide my hand drill.
Pictures later, having too much fun right now.
Gee, what if this all works out?
Well, if it doesn't--if I burn up this motor too in torture testing to
come,
I'll buy a new one from TNC scooters. They should have stock of this
MY1018 very soon.
I consider it to be a consumable item (not like a BL $$ hub motor).
So, to have a spare, ready to slap on, it a good plan.
And if it doesn't burn up on 36V and flat-out running, after this
force-cooling mod?
How long will it last? I'm curious to find out.
Cheers,
Reid
----
Next posting will show pictures more or less self explanatory.
I'll caption them only as needed.
Posted by: Reid Oct 9 2006, 06:47 PM
The inside of the diecast motor cover carries the brush plate:
phenolic board standing about 3mm off from the inside surface of the
cover.
This plate has a 3mm air gap. It stands on four lugs, one of which is
noted by the white cursor.
The lugs are swedged a bit to hold the phenolic.
Removable by prying, but I didn't wish to disturb things--there is no
need to do so because the metal drills so cleanly.
http://img20.imageshack.us/img20/7898/screenshot045wr6.jpg
The cover has already been ventilated--air will pass around the
perimeter of the brush plate
and also around the center hole, hitting the commutator and brushes
with cool air.
____________________________
http://img176.imageshack.us/img176/5081/screenshot044ls4.jpg
On the right is the very same cover as above. See the phenolic board
peeking through the air holes.
Note the other cover--the gear-end cover of the motor has twelve air
exit holes.
These will be baffled to prevent ingress of water splash, no worry
about that.
____________________________
http://img242.imageshack.us/img242/2967/screenshot043xd6.jpg
Here are the major parts of the MY1018. So simple.
OK: the extra (leftover) brush end cover from the old motor is to be
used as a plenum cover;
that's it laying atop the new motor's brush plate cover.
It will get a 3/4" copper elbow fitted to its center, next step.
I will grind off its flange and attach it with self tapping screws to
the ventilated cover.
Air will be forced into the plenum, go through the holes, around the
brush plate, through the motor,
carrying off waste heat generated in the armature.
This is all done to allow the motor to live longer at high loads, high
speeds.
As a sealed motor, it gets to be like a miniature oven inside.
The modification will make it like an oven with an open door, and a fan
blowing on the turkey.
It should be less liable to roast turkey this way.
I am, of course, the turkey, if the armature...roasts!
Note how cleanly the diecast zinc drills. This was a great
troublesaver, to not have to pry out the brush plate.
Note the little gear case? That is to be packed with grease, per usual.
I will vent the case, though ,with a couple of small holes.
When a case is packed full of grease and then the gears are run,
thermal expansion plus the churning, forces excess grease out through
the "sealed" beaings
*there is no such thing, really*.
The bearing behind the output sprocket is of the metal shielded type.
It will pass excess grease readily, until the excess is relieved.
The bearing behind the drive pinion (integral with the armature) is of
the rubber "seal" type.
This type passes less grease, so relatively little grease gets into the
armature housing.
Anyway: by making two small grease holes remote from one another
I can "change" the grease in the compartment from time to time, if
thought needed,
without opening the case up.
Two small self-tapping screws will seal the holes when they aren't
needed.
Next step: mate the fake cover to the real cover and begin air flow
tests (that is, guess whether I've got a free enough passage for the
air pressure the blower will provide. If less restriction is called
for,
more holes will be drilled, no sweat.
So it goes...
fun!
Posted by: fukenfooser Oct 9 2006, 07:15 PM
"MY1018"
I'm following this with interest.
Because I just recieved my own MY1018.
Not the geared one, a different one.
"MY1018 CE
Voltage: 24VDC Rated speed: 2500 RPM
Rated current: 16.5A Output: 300W
Jx JX Motor Co.,Ltd"
Was picked up off E-bay
$.99 + S&H of $20.00
Black body, Silver end caps
about 4" Dia, and 3.4" long
Has 4 bolt mnt plate built on
Shaft= 15/32", with a .393" dbl flat sided sprocket mnt under 19/64"
threaded end
also has dbl flat spots on main larger shaft area about 3/8" across
flats
11T #25 chain size sprocket came on it.
ZERO air cooling as no holes at all
front end plate has 4 screws, rear has nothing
Spins either way with 12 VDC to wires, (cw or ccw).
When shorted, (wire held together) the motor is harder to turn.
This is a test we, (R.E. people, aka windmills ect,ect..)
do with DC motors to see if worth picking up when found in travels.
I was working on building a mini E-scooter or something like maybe
the "Sparky II".
So watching what you do to help cooling will be of interest !!!
The "Solar Scooter" I was given has gotten me bitten to have
a faster E-Ride Toy.
The ss has a motor with built in jackshaft like the newer MY1018's
have.
All belt drive, but limited speed as being a "old fart" type, 15 MPH,
but
hey, I't do wheelies if rode standing and being in turbo speed, (button
on)
when starting from dead stop just do like on a bike, pull back on
handle bars a bit
as motor starts to push it forward!
Would be great for parts if it wasn't a working E-ride.
I should just mod on it but hate to ruin it.
Still thing it would be cool chopped out.
http://www.visforvoltage.com/forums/uploads/post-22-1160435710.jpg
Attached Image
Posted by: Reid Oct 9 2006, 08:22 PM
Good! I'm glad that the general principle here is of interest to folks.
We are hot rodding mini motors.
Bearings:
The perversity of manufacturers...
The ball bearing, as a -general rule- should be a light press fit on
the shaft.
It should not be a slip-on fit or the shaft may at times spin in the
bearing's ID bore,
making wierd noises that come and go, and eventually possibly causing
shaft damage.
Unite had the bearings set up as a bare slip fit on both of the two
motors I've seen now.
A small sin in my opinion, but a sin nonetheless.
So, just as good, even better than press fit here, is to slip the
bearings back onto the armature shafts
using a locking agent. "Stud and bearing mount" is another name for
this thick red anerobic cement.
Use it sparingly--a dab'll do ya.
Now, the other side of the coin: as a -general rule- the ball bearing's
outer race should be a bare slip fit in the supporting cover's bore.
This allows for thermal expansion. IF both ID and OD of the ball
bearing are press fit-tight, there's no relief for strains engendered
when the motor heats or cools.
Shortened bearing life may result.
Radial load ball bearings like these are not meant to take much of a
thrust load.
On the other hand, the castings are thin and somewhat flexible/springy,
to a couple of thousandths of thermal growth----differential of
dimensional growth between armature shaft length and housing length.
Unite provides (correctly) a spring washer behind the brush-end ball
bearing, to keep it all lightly pressed forward, to prevent end shake
rattles that could otherwise occur
(and prevent the -wear- to the castings' bearing bores that woud
entail).
If the OD bore is worn or slopped, it -might be OK- to apply a bit of
silcone rubber type of glue.
If the parts are grease free... the silicone rubber is elastic enough
and yielding enough to allow thermal strain relief, while also
immobilizing the OD of the bearing from chattering or spinning out in
the bore (so long as the bearing runs without internal failure, ie:
grinding up. Then somthing's gonna give and you'll know it by loss of
power and terrible noises, probably.
See that Unite uses a rubber "sealed" pinion-end bearing here.
This is to better exclude gearcase grease.
However, such bearing seals are only rated to keep ball bearing grease
-in- the ball bearing.
They cannot prevent grease or oil migration shoving or leaking
-through- the bearing from an adjacent grease-packed case.
But, as noted in a prior posting, the output shaft bearing is only
metal "shielded", and so,
leaks excess grease to the outside world, in preference to the grease
going back into the motor.
So, no problemo.
If it were a critical application, an "umbrella seal" would be called
for.
Here there is no room for, nor any real need for an umbrella seal (It's
a sort of flanged rubber compression seal).
__________
Bearings cemented in place for silent running
http://img243.imageshack.us/img243/5867/screenshot046sc7.jpg
Posted by: Dom Oct 10 2006, 09:19 AM
Good stuff Reid
I must have missed a post somewhere -you finally got a proper
replacement motor??
With all your cool plans -this motor should be a rocket!!
I was surprised when i put my controller(which never felt like it got
warm ever) in my battery bag -the bike cut out after a few minutes
normal running.
Took me a while to work out it needs air running over it -even a small
amount!!
Cheers Dom
Posted by: Reid Oct 10 2006, 10:07 AM
Yeah, Currie at last sent a new motor.
I was just humbled by my ignorance again:
-motor partly assembled (sans output gear),
I ran it from a 12V battery, holding the brush cover in place.
Rotating the cover anti-motor rotation, the armature spins faster,
smoother!
Ooooo (I thought!) More power at speed!
Then I smelled smoke. Glanced at the clip leads.
Melting vinyl. I pulled off the brush cover pronto to prevent the
neighborhood from burning up.
hahahha.
Stufu just learned: advancing the brush timing much past (presumed
neutral?) factory setting,
increases no-load current draw enormously.
I will forego timing advance for now.
My fingertips are blistered! (not really)
I hate the smell of blue smoke.
Break---finish it later today.
Fume meanwhile.
Cogitate.
Grow Less Stupid
(maybe!)
--------
Currie seals the controller in an airtight cubby.
I don't know how they get away with that.
It's just above the b.b.; a totally closed box,
designed to hide the controller and...retain rain water.
cheers to Dom from me,
Mr. Dummy
Posted by: Reid Oct 10 2006, 07:27 PM
http://img353.imageshack.us/img353/6299/screenshot047hy0.jpg
http://img487.imageshack.us/img487/4360/screenshot049pl2.jpg
At this writing the brushes are running-in on a 12V feed, no load.
The plenum cover will be screwed on with sealant
and the unit painted with Krylon satin black for appearance and for
that little extra bit of cooling afforded by a thin coat of black paint
(black is a cooling color).
The 3/4" copper elbow is an interference fit. The slight protrusion
inside the cover is riveted over;
nicked with a chisel and cemented with red bearing locker.
It should hold OK. Don't want it to fall out, ever.
I've decided to mount the motor in a new orientation:
the big circle hanging down instead of up.
It'll look a little neater.
The blower will get mounted next
to the underside of the existing seatpost rack.
It is a 24V blower. The bike is 36V.
It was discussed here on forum, and determined earlier, that the
simplest way to drop 12V
for the blower is to run a 12V 1A auto lamp in series with the blower
supply.
The blower will be fed in parallel with the motor.
Therefore, its action will be entirely automatic, in sync with motor
speed/cooling needs.
The two long, protruding RH screws are temp. caps for the grease
input/output holes I just drilled into the gear case.
They'll be replaced with stubby screws. By this means I can regrease
the gear case as desired without stuffing it over-full.
It has occured to me that I -could- engineer a grease pumping
system--grease pumped by the pinion and driven gear, recirculating, and
shot out into the mesh of the pinion-to-driven gear.
That's for the next motor. This one I just want to run asap even before
installing the blower.
I'll just keep the speed down for now until the blower gets fitted,
holding my speedgreed to 17 or 18 miles per hour; it'll be OK at that
number.
Once blown? Full bore and 25 per!
Posted by: Reid Oct 10 2006, 10:38 PM
Here's a blowup of the Currie Izip cruiser motor drive
back when it was bone stock (Aug 13th)
http://img463.imageshack.us/img463/9148/screenshot052zp6.jpg
Now it's time to test the blower. "24V 10W", it cost about five bucks
from Marlin Jones electronics (thanks fechter for the lead)
The motor, even idling on 12V grows warm to the touch.
Next I lashed up the blower.
It's so quiet on 24V that I think it's wiser and better to
run it full power all of the time.
After five minutes the motor case was cool to the touch
http://img174.imageshack.us/img174/3953/screenshot053pu1.jpg
Quite a breeze is going through the motor.
The motor was stone cool after five minutes of blower operation.
The two units are running--the frash flozen motion.
How to mount the blower to the seatpost rack?
http://imageshack.ushttp://img140.imageshack.us/img140/4064/screensho...
"The thin' hay no room!" says Ren.
Never fear! I, Stimpy, have a hAcKsAW.
"You are a genius idiot"
Righty, Ren.
We are a team.
http://img183.imageshack.us/img183/1369/renandstimpytn0.jpg
"Dom will be so jealous...." (audio joke)
http://img174.imageshack.us/my.php?image=sound128ek8.swf
Posted by: goofproofpc Oct 11 2006, 12:19 AM
QUOTE
"Dom will be so jealous...." (audio joke)
http://img174.imageshack.us/my.php?image=s...sound128ek8.swf
LMAO............. Dude might want to consider seeing a
shrink.........lol
Matt
Posted by: Reid Oct 11 2006, 01:09 AM
Doktor Felix Risinggarter, consultant:
http://img142.imageshack.us/my.php?image=sound129rg1.swf
----
If Matt were here I would paint him like this (j/k)
http://img145.imageshack.us/img145/373/screenshot057zi9.jpg
for disrespect of a comedian.
Hanging? Mandatory of course.
I kid a lot.
The project should be basically finished by tomorrow night.
For the voltage dropping lamp I think I might use this 11W non-halogen
PAR lamp
already on hand:
http://img222.imageshack.us/img222/4794/screenshot058lt3.jpg
If I spritz the lens with red Krylon "Stained Glass Color" paint,
woot: what a nifty tail light. Wide flood too boot.
I -think- the blower motor will be audible enough, that I'll know it's
running.
That is, if the blower were to fail and I did not realize it (the lamp
was gonna be a tell-tale in my line of sight), I could fry the motor.
Let's see. One guess leads to another.
Matt, go have a beer and have fun.
BTW, is your sister free on Saturday?
no?
How about Wednesday?
Oh, nevermind, lol!
Posted by: Reid Oct 11 2006, 09:05 AM
OK, enough joking around; back to work:
There's not enough room on the seatpost rack.
http://img167.imageshack.us/img167/1674/screenshot063br7.jpg
The SLA battery is double-stick foam taped to the rack.
Man! It's really on there! I can't pull it off.
Why bother, anyway? It's in its best postion.
Hacksaw two sides...
http://img133.imageshack.us/img133/6008/screenshot064it8.jpg
Bend the flange and off it breaks...
http://img100.imageshack.us/img100/536/screenshot065vn4.jpg
Now there's room...
http://img218.imageshack.us/img218/4764/screenshot066cx8.jpg
The light bulb for a dropping resistor:
Did not work according to theory.
The blower's current draw is directly dependant on the load.
Since I've choked off the blower's output, it draws less current.
I found that even a .6A 12V bulb only dropped about four volts. Not
enough.
Trial with lightbulbs on hand showed that either a 150W 120V regular
bulb would work (too bulky!)
OR, that slim 100W halogen seen in the top picture.
Both give virtually identical voltage drops. Odd, eh?
It's because the relatively cold tungsten filaments have very different
resistances,
explained by the very different lamp technology between the two.
I'll use the slim halogen for a self-regulating dropping resistor.
There is -some small measure- of voltage regulation:
When tungsten is hot, like copper, its resistance increases.
This sort of application is technically called a "barreter" resistance.
Crude, but I don't have to go mess around with power resistors, etc.
The lamp only gets warm to the touch. I guess it's dissipating less
than five watts.
Where to stow it?
How about in here? Padded, of course.
It'll never break or burn out.
http://img144.imageshack.us/img144/8889/screenshot062oo3.jpg
___________
This is real-time reporting of home brew modding by a hacksaw and
solder guy.
I'm posting pictures as I progress and think it through one step at a
time.
Now I am wanting a DPDT switch so I might have the blower run either
from the motor supply (variable)
-OR- flip the switch to run full tilt.
That way I can have (or avoid) the soft turbine whoosh when the bike is
running slowly--when full cooling is not needed.
-OR- if the motor's hot I can cool it down fast, even while the bike
may be still.
I hope this is getting interesting in its humble, cheap-way manner of
style.
More later this AM
Reid
On to the blower:
http://img150.imageshack.us/img150/1541/screenshot061lp7.jpg
Posted by: Dom Oct 11 2006, 09:05 AM
QUOTE (goofproofpc @ Oct 11 2006, 12:19 AM)
QUOTE
"Dom will be so jealous...." (audio joke)
http://img174.imageshack.us/my.php?image=s...sound128ek8.swf
LMAO............. Dude might want to consider seeing a
shrink.........lol
Matt
Don't know if i went GREEN but i went pretty RED from LMAO double
time!!
You'll definately have a rocket there Reid!! Top Stuff!!
You need to have some of those wind ribbons so we can see the hot air
coming out!
Cheers Dom
Posted by: Reid Oct 11 2006, 09:22 AM
I'll hang 'em to me mouth...
http://img180.imageshack.us/img180/7492/mickymouselockwl5.jpg
mouse!
Posted by: Reid Oct 11 2006, 11:10 AM
While waiting for epoxy putty to fully harden so it may be filed:
To increase the pressure delivery of the blower
the inside of the cover, which has a uselessly wide air gap from the
cage,
is getting filleted with putty to decrease that gap.
Then I file and fit by hand and shoot for 1 mm or less of air gap.
Don't want it to scrape, but don't want to waste air.
The centrifugal principle depends on inertia of air put to great
velocity.
Curiously, but it makes sense: when we block the output of a
centrifugal fan, what happens?
-The motor unloads and speeds up greatly. It draws less current.
-But, as air delivery is progressively choked off, the pressure goes
up.
Makes sense, huh?
I want max pressure from the fan, to put max volume of air through the
restrictions of the hose, fittings and motor cooling path.
I figure to fiddle this project for these few days. It's all good.
Not sure just how much the fan-tuning really counts for. Maybe nothing.
Maybe just that little bit of extra air delivery---there can't be too
much but there could be too little.
Have to make a filter/bug excluder too.
And figure how to dress the seatpost rack over with fabric so it looks
half normal.
That leftover cover from the kiddie trailer--yellow ripstop nylon.
I can't sew but I can velcro and glue
and hacksaw and solder, lol
Posted by: Recumbenz Oct 11 2006, 12:36 PM
Reid:
This is really fascinating! The MY1018 promises to be a really
cost-effective motor for bottom drive applications so your hot-rodding
efforts are being closely followed.
Question:
Simply drilling holes as you've done will permit a certain amount of
air circulation through the motor to dissipate heat. Is it possible
that adequate ventilation could be achieved without the all the hassle
of a motor driven blower? Passive pressurization could consist of
nothing more than a forward-facing funnel directed into that copper
elbow. As soon as the bike is moving there'd be a lot more air moving
through the motor than stock.
A passive ventilation mod would be a lot easier to live with yet might
still do the job ??
Peter
Posted by: Reid Oct 11 2006, 12:45 PM
Hi Peter, best regards are offered to you for your ideas.
Yes, I thought of that too. I don't know. Somelse will take that
gamble.
Let's presume for a moment that a funnel (like old ships used) would
ram enough air in
at speed, to keep the motor cool enough.
OK, now the next scenario: Climbing a grade with the full force of 36V
jamming maybe 25 or more amps through the motor. And no headwind. Maybe
a tailwind.
I'd worry that it'd fry under adverse conditions.
I figure we must carry off up to 400W of waste heat at times.
If I don't burn this motor I'll learn in time just how long it lasts,
it being brushed and all.
Sort of a consumable thing, is how I look at it.
I would be delighted to get a thousand miles before the next motor
failure. Delighted and amazed.
Then put in a new motor---swap in a new brushplate and armature and
driven gear---that's all that wears (drive pinion being machined from
the armature shaft).
I don't think gear wear will be a problem.
I think it'll be heat strains, then commutation troubles.
Nearly ready to trial it,
cheers,
Reid
____
The motor is dry-fitted
The lamp-resistor is stuffed inside the seatpost rack's hollow tube.
The blower is mounted
The vinyl hose is getting wrapped in that sort of spiral black cable
wrap, to dress it up
The controller needs some sorting out of its wiring connections (TNC
controller giving me fits)
Hook the blower wires to the main battery supply (for now it'll be just
that one way).
Need to pump grease into the gearcase of the 1018,
install the grease retaining screws
and go for a ride.
Posted by: Buzzz Oct 11 2006, 01:13 PM
" Dom will be so jealous " lol... oh my god Reid.. you have just
surpassed any level of weirdness i have ever seen before !!!! top job !
lol... oh god.. my ribs hurt !
Posted by: Reid Oct 11 2006, 02:42 PM
I'm just being a funnyman. Not weird and not mental.
Some people, I swear! Like, so--I like pancakes. That's normal enough,
right?
Right??? OK. So I like pancakes.
I have trunks full of them.
_______________________________________________
Here's the general look at the moment
http://img196.imageshack.us/img196/7021/screenshot068yd9.jpg
I cannot get the TNC 36V controller to behave properly;
can't figure out why the throttle does not work correctly..
So I'll reinstall the Currie's stock 24V controller which worked
flawlessly on 36V.
Have to solder five little wires back together. Oh bother.
So while I break from tedium I just took these pictures.
It is a nice day in Miami. About 75F and partly cloudy, low humidity.
This is the beginning of our six months per year of about the best
weather in the USA.
Don't move here though. It's too crowded.
And no one speaks Henglish hanymore. Only Cockney. But that's only me,
joking again.
Pardon if I log off? I am hungry.
Pancakes, you know...
lol, but oww, I am tired of messing with the incompatible 36V
controller.
Into the bit bucket for it.
Just a few more connections and
http://img383.imageshack.us/img383/8241/screenshot069qn0.jpg
Captain! Didja see 'er? A great blue whale! Look!
THAR SHE BLOWWWWWS
*am looking now with imagesearch for a woodcut of Ishmael, the narrator
of Melville's "Moby Dick".
Will post the first image I find of "Ishmael".
OK.
Posted by: Reid Oct 11 2006, 02:47 PM
no one should ever not not hijack any thread of mine which I didn't
start in the first place.
clear enough?
Imagine him as a whaling sailor?
Captain! Didja see 'er? A great blue whale! Look!
THAR SHE BLOWWWWWS
http://img96.imageshack.us/img96/4651/ishmaelzm3.jpg
"Ishmael" is his name, it really is.
Forget whaling. Imagine him on one of Steve's monkeyshine bikes
---
Back to reality and the $*#*%*# controller issues...
PS: "thar she blows"
http://img279.imageshack.us/img279/4237/screenshot070ue7.jpg
get it now?
not funny?
well! you should try comedy sometime, mr. whoever you are who's running
up the read counter.
FIVE people are following this thread; no more than that. Who's running
up the read counter?
I'd like to know.
Lessee: there's me and Dom and Buzz and a couple others and then
there's me and me and me me and me and me me and me and me me and me
and me me and me and me me and me and me me and me and me me and me and
me me and me and me me and me and me me and me and me me and me and me
me and me and me me and me and me me and me and me me and me and me me
and me and me me and me and me me and me and me me and me and me me and
me and me me and me and me me and me and me me and me and me me and me
and me me and me and me me and me and me me and me and me me and me and
me me and me and me me and me and me me and me and me me and me and me
me and me and me me and me and me me and me and me me and me and me,
etc.
So I guess it's all my fault. Usually is!
I love to laugh and make people happy.
I love to laugh and if people don't like it?
(I cannot speak that language here)
g'day
Posted by: Reid Oct 11 2006, 04:55 PM
Before the rebuild this motor was notably noisier than the original
that came with the bike.
I just filled the gear case with Valvoline synthetic bearing grease.
One shot seems to be enough.
http://img516.imageshack.us/img516/8485/screenshot071db8.jpg
The motor had run for ten hours last night, unloaded, at low speed.
The shafts now have their bearing cemented to them
The bearing seats in the castings were given a smear of a synthetic,
rubber glue (oil and grease proof stuff). So I know nothing is spinning
or working in bores or on shafts.
The Currie controller has just been reinstalled. It works great.
This motor is positively quieter than its predecessor.
It makes but a fraction of the whine that it made a few days ago before
the teardown.
The bike runs -great-.
But yeah, the motor still makes a lot of waste heat.
After a two mile full throttle run the case temp. was 135F.
This is surely cooler than it would've been without the modest flow of
cool air blown through.
The blower is wired to the main battery. I left it running after
parking the bike.
The motor was exhaling hot air, as expected.
But it cooled down quite quickly--in five minutes or so.
I do not know yet whether the blower delivers -enough- air to ensure
the motor's survival at full, 36V throttle.
I don't want to risk burning this armature too, not until I get a spare
MY1018 from TNC scooters.
Once I have my spare? Time for another destruct test.
And -if- the armature burns up, I'll make another blower system. Forced
air---even positive displacement, such as a bellows is not out of the
question. A piston pump would be noisier.
This blower, though, makes a great TURBINE sound. It's sort of cool.
Summary to wind this up for now:
The motor does run cooler.
The blower cools it down.
The motor runs very much quieter than before.
The predominant whine seems as if it comes from the controller.
Do controllers whine? I suppose it's just transmission of noise from
the gear to the b.b.
Its a very speedy bike for what it is.
It feels solid as a rock and it is a happy bike once again.
So am I!
(happy, I mean. I am not a bike)
Posted by: jondoh Oct 11 2006, 05:36 PM
135 deg F is around 57 deg C which is in the somewhat safe range for
most electronics. Still a little warm-- but not warm enough to bake
cookies.
I have to think that even that heat will shorten the life of the motor
compared to larger motor or the same motor run at lower power. Maybe a
year or two depending on how often it's run. It would be nice to find
out. Keep up the good work!
Posted by: Reid Oct 11 2006, 05:56 PM
Yessir, I agree: overstressing a modest motor like this one will vastly
shorten its life.
Although the outside case temp. was 135F, it would have gotten hotter,
I think, had I run longer.
And does the outside case temp really -tell what the armature and
brushes and commutator are feeling?
I suppose the windings are much, much hotter.
At what temperature does modern wire enamel begin to char? Hmmm... 500F
perhaps?
I need to find that out.
If I had taken more time I'd have installed a temperature probe
to monitor the core of the motor housing: say, poking in between a pair
of the magnets.
Still, I can't say what the armature temp is running until
a) it fries and b) I learn what is the destruct temperature of enamel.
After all, the main place of heat production is in the commutator and
in the windings.
Good thoughts--thank you for helping me along.
The point of this exercise is to see if a cheap motor can live along
hostile terms,
and for how long. Seven miles is it for the stock motor.
We'll see... now if my "improvements" were worth the doing.
cheers,
Reid
Posted by: Nickf Oct 11 2006, 05:59 PM
Great thread Reid,
Nice to see all the photo's, I can see this developing into a a
trend....
I think maybe your new motor might work better with the blower. When I
fried my brushed motor it never worked the same and generated a lot
more heat. I've heard other saying the same thing - that no matter what
they do they never quite get the same performance. Maybe the heat and
current combo damage the magnets?
Posted by: csaudio Oct 11 2006, 08:12 PM
Reid
Controllers whine. If your ears are really good you will hear more of
it. The switching frequency of most controllers is less than 20kHz.
You can think of your controller housing as a tweeter.
Hub motors also whine for the same reasons. High freq switched signal
in to the motor turns it into a tweeter.
csaudio
Posted by: Buzzz Oct 11 2006, 08:31 PM
What are the effects of higher or lower frequency controllers ?
efficiency ? sound ? performance ?
Posted by: Reid Oct 11 2006, 08:36 PM
Hi Nick,
Please tell us about the circumstances that led to your damaged motor?
I've read that even one shorted turn will spoil a motor's performance.
As for heat damage to neodymium magnets? They are not the best for heat
resistance.
The four neodymium magnets of the Unite motor are, I suppose, mounted
the same way in all modern motors?: the core of the structure is an
iron or steel band, to which the magnets are cemented? or otherwise
fastened. The band is cast into the zinc housing of the motor.
If magnets weaken, yeah, the motor will weaken. But a shorted turn is
more likely (I think)
>From Wikipedia's entry on the subject:
QUOTE
A neodymium magnet or NIB magnet (also, but less specifically, called a
rare-earth magnet) is a powerful magnet made of a combination of
neodymium, iron, and boron - Nd2Fe14B. They have replaced marginally
weaker and significantly more heat-resistant samarium-cobalt magnets in
most applications, due mainly to their lower cost. These magnets are
very strong in comparison to their mass, but are also mechanically
fragile and the most powerful grades lose their magnetism at
temperatures above 80 degrees Celsius High temperature grades will
operate at up to 200 and even 230 °C but their strength is only
marginally greater than that of samarium-cobalt. Neodymium magnets (or
"neo" as they are known in the industry) are graded in strength
from N24 to the strongest N54. The number after the N represents the
magnetic energy product, in megagauss-oersteds (MGOe) (1 MG·Oe = 7,957
T·A/m = 7,957 J/m³). N48 has a remnant static magnetic field of 1.38
teslas and an H (magnetic field intensity) of 13,000 oersteds (1.0
MA/m). By volume one requires about 18 times as much ceramic magnet
material for the equivalent magnet strength. The neodymium magnet
industry is continually working to push the maximum energy product
(strength) closer to the theoretical maximum of 64 MGOe. Scientists are
also working hard to improve the maximum operating temperature for any
given strength.
Note that there are many grades. Inferred: the weaker grades are less
liable to heat damage.
__________
Henry's Model T generated its lighting and ignition current supply by
flywheel magneto.
The best magnetic then was glass-hard tungsten steel. Many were the T
magnetos
I'd remagnetize, using the coil sheet of series-wound bobbins, against
which it worked,
to produce the required magnetic field.
http://img133.imageshack.us/img133/1411/screenshot072te0.jpg
If a T overheated badly, the magnets often lost their mojo. Weak
ignition resulted.
The system generated AC current. In time, normal engine temperatures
and vibration weakened these magnets. However, they can always be
recharged.
I wonder (don't have a clue) how they put the magnetism into our
manufactured "nib" magnets?
Early radio speakers had U shaped hard steel magnets. By winding turns
of enameled wire around
an age-weakened magnet, and then goosing it with a fully charged
-large- capacitor of hundreds of volts potential, I found it easy to
restore the magnet--in a flash, literally. I'd always fuse the wire in
doing this trick. That quick -break- of the magnetic field is what
kicked the magnet to fully saturate.
I digress.
______
The bike battery is charging. Perhaps later tonight I'll go out and
make runs up and down a smooth, residential boulevard nearby. With the
Raytek IR thermometer, I'll check the motor housing temp at half mile
or so intervals. At full throttle, the temp is bound to rise---to some
point yet to be learned.
I just don't want to kill the little bugger quite yet.
Thanks for positive reactions to this mixed bag-of-a-thread.
I'm glad no one's complained of the "entertainment" aspects!
That'd be such a shame if they did. See,
I'd have ta go kill'm.
(jk!)
Posted by: Reid Oct 11 2006, 08:54 PM
QUOTE (csaudio @ Oct 11 2006, 08:12 PM)
Reid
Controllers whine. If your ears are really good you will hear more of
it. The switching frequency of most controllers is less than 20kHz.
You can think of your controller housing as a tweeter.
Hub motors also whine for the same reasons. High freq switched signal
in to the motor turns it into a tweeter.
csaudio
Understood and agreed, but no, this isn't that sort of high pitched
stuff.
I wouldn't hear above 10k anyway.
This sounds like the old motor whine I know so well from the Currie,
only now it
-seems- to be coming from the cubby where the controller resides,
instead of from the motor.
It's probably due to my having repositioned the motor: it hangs -down-
insead of aiming upwardly.
(see picture previous page). Just such a move as this, plus the
prop-supporting screw I've set to
prevent the heavy mass of the motor from vibrating--these things have
changed the acoustic of the bike frame.
It may account for why the motor is so much quieter.
More likely it's a combination of things.
I've heard odd whizzes and buzzes from the two Unite motors in the
past:
due to bearings squizzing in their cups bearing ID's slipping
intermittantly on the shafts.
Now with everything "right" there's nothing to make odd sounds.
Also, I paid attention to gear mesh in setting the two end plates.
There's a small amount of radial slop movement in the die castings.
I ran the motor on 12V, moving the plates a bit this way and that until
it was quietest
then cinched the screws and applied wicking grade locktite to the joint
to exclude water ingress.
Water will find its way into ungasketed joints.
Thanks for helping guy,
Reid
Posted by: Dart Man Oct 11 2006, 10:32 PM
This thread was very entertaining. Thanks for the laughs Reid. Did you
ever get your new V-brakes to work better?
Posted by: Reid Oct 12 2006, 05:19 AM
I got the rear brake (still all-stock) working better by following your
cue and scrubbing down the brake pads. They were glazing with rim
metal. The pads grip and are OK.
Front brakes: am awaiting delivery of a Bike Nashbar brake booster
(fork truss).
This'll make my front brake lever twice as stiff. The springer fork
really springs and twists badly at present
-----
Current local weather condition report. Why?
http://imageshack.us
An hour ago I took the bike to the local high school one mile away
(four AM local time).
The quarter mile running track... (idea from Paul and Scott).
Took along the Raytec thermometer.
motor case temperature, start of the track run: 98F
Cyclometer says:
3.46 miles
23.1 average speed
24.6 max speed.
9:04 elapsed time.
temperature at the finish of the track run: 108F
Summary: under these conditions I'm sure the motor would be just fine.
The commutation in damp air must be ideal
(graphite brushes need moisture to make good commutator film).
Am surprised the temp. rise was so little.
A dissimilar (less stressful) run yesterday afternoon took the motor
case up to 135F in less time.
Perhaps it is the cooler, damper night. Perhaps also that it was an
uninterrupted run?
The motor cooling goal may well achieved.
More runs, more data.
I need a Drain Brain.
Posted by: Reid Oct 12 2006, 05:34 AM
Musing aloud:
It is well known that graphite becomes abrasive if moisture is entirely
absent.
Brushed motors cannot be operated in outer space for this reason.
Now, if a bike motor is brushed, and if that motor is essentially
sealed (as they all are in stock form),
and if the motor is run, it gets hot in there. Heat drives out moisture
from the case.
The brushes go bone dry. Brush friction (and wear) increase.
Commutator filming (a continuous, constant process) suffers.
Electrical resistance heat increases. The commutator grows hotter.
The motor efficiency falls, owing to imperfect commutation.
----Now flip the coin:
The motor, ventilated and run in cool, damp night air:
All the bad things above are reversed. Low brush friction, high
commutation efficiency.
Low motor temperature rise.
Summary:
In the track run report above this posting there's enough data to make
this hypothesis plausible.
Point in formation:
A fully sealed brushed motor is a bad propostion, period.
For it will drive out water vapor as it heats, decreasing commutation
quality.
If I lived in a desert region and ran this bike in great dryness,
I'd make a trial comparing dry air running, against humidified air fed
into the motor.
By expedient of a simple evaporative pad above the blower intake
water vapor can be added to the motor's environment.
Posted by: Reid Oct 12 2006, 08:05 AM
I've posted a link to this page, and a synopis over at the Maintenance
Forums.
There are real electrical pros there. Perhaps one of them will add to
our knowlege.
If so, I'l trans-post the information here.
Beginnning to study wire enamels.
>From the earliest days (my 1887 C&C motor is one witness), the armature
wire required to be wound in slender cotton, or preferably, silk
thread. The armature was then dipped in a varnish or shellac.
This general sort of insulation was nearly standard up to about 1920 or
so, by which time phenolic resin baking varnishes had been developed.
I've a Violano Virtuoso of 1926 vintage. Its motors are all enamel
wired, no cotton or silk. The earlier Violanos, going back to 1912 were
similarly done. The makers of that machine were doing state of the art
motor winding with top quality materials. The survival rate of these
orgininal magnetic windings today is on the order of 99 percent---they
are that well done.
-----From the war years, great advances in wire enamel. Here...
QUOTE
http://www.chemcases.com/silicon/sil10one.htm
10. Small, Efficient Motors
Silicone materials exhibit unique properties based on their chemical
structure.
But those properties turned out to be less than ideal for insulation.
In less than sixty years, manufacturing grew to more than 1 billion kg
of silicone resins made by Rochow's process.
But only a small fraction, about 10%, of that production ended up in
the small, efficient motors. Silicone polymers failed to have the
properties suitable for widespread insulation uses.
The biggest issue for efficient motors was the insulation for magnet
wire;
the copper wire windings that wrap the rotating electromagnetic coils.
The rotating coils in a generator produce the current that can be sent
to motors.
In a motor, the process is reversed and the current causes the rotor to
rotate and produce work.
General Electric's engineers could develop a long list of ideal
properties for the magnet wire insulation.
They called this insulation 'wire enamel'.
Their ideal wire enamel should have as many of the following properties
as possible:
http://img101.imageshack.us/img101/7826/screenshot074mp9.jpg
At least two dozen factors needed consideration. Some were more
important than others.
In a wire enamel, resistance to the UV rays of the sun would be less
likely to cause a problem than,
let's say, low resistance to electrical current flow.
Before the fact, before Eugene Rochow had his magical laboratory day in
1940,
no one could predict the inventory of properties that silicone might
have.
But with silicones in hand, GE's scientists and engineers sensed
trouble:
they could make silicone resins and impregnate them into glass tape
with excellent overall properties. But wire enamels made from
silicones gave real problems. Wire enamels had the required heat
resistance, but they were soft, not hard.
The enamels were easily cut by adjacent wire. Silicones were porous to
gases and water.
Many of these poor properties were unexpected and sent the scientists
in two directions.
First to understand, if they could, why the silicones failed and to
try to improve those properties. Secondly, the scientists renewed
their quest for other compositions that would work
as wire enamels.
GE's first approach to try to fix the silicones did not work very well.
Their scientists became aware of a Canadian research development, a
resin called polyvinyl formal.
GE licensed the Canadian development. It certainly was not GE's first
choice to use technology
developed by others; what was more important, was finding the best wire
enamel.
This material met the test of the broad range of properties, and by the
early 1940's
this resin, now called Formvar® by GE, became the magnet wire enamel
of choice.
The one property that Formvar® did not have was the extremely high
heat resistance of the silicones.
It was only a Class F, 150 degrees Celsius insulation, not the Class H,
180 degree
insulation that silicones could achieve, in theory.
But the enamel applied so easily, performed so well and could be coated
in such thin layers
that smaller, more efficient motors and generators came forward.
>From the beginning, GE scientists saw that silicones would have
thousands of uses beyond electrical insulation.
They succeeded in opening up many opportunities. Scientists from
around the world began to look
at other polymers that would show the complex sets properties required
for our modern world.
Chemists and engineers developed marvelously improved materials.
Posted by: csaudio Oct 12 2006, 09:21 AM
Hi Buzzz
Higher switching frequencies yield higher efficiencies as well as
allowing less iron to be used in the inductors in power leg of the
circuit.
At higher freq the FETs switch quicker and can operate more safely at
high power compared to low freq switchers.
It costs more to make the driver circuits so the cheap controllers will
have lower frequency switchers.
In an airplane the AC power is produced and distributed at 400 +Hz in
order to reduce the needed iron weight.
csaudio
Posted by: fechter Oct 12 2006, 10:25 AM
There's always an optimum switching frequency. If the motor is big and
has lots of iron, the core losses will increase at a higher switching
frequency. Switching losses in the FETs also increase. You just want to
make sure the frequency is high enough so the flux doesn't have enough
time to completely build or saturate.
Interesting about moisture and motor brushes. I never knew that. I
guess that helps explain why the brushes in my Zappy motor look
practically new after 400 miles despite being run at over 4X the design
power.
Posted by: Reid Oct 12 2006, 11:13 AM
QUOTE
There's always an optimum switching frequency. If the motor is big and
has lots of iron, the core losses will increase at a higher switching
frequency. Switching losses in the FETs also increase. You just want to
make sure the frequency is high enough so the flux doesn't have enough
time to completely build or saturate.[/COLOR
This explains to me why the TNC 40A 36V scooter controller groaned my
bike at low throttle openings.
I had relatively little bottom-end torque. So, it was not a defective
controller. It was my defective crossover application of a big-motor
scoot controller to a small gearmotor.
QUOTE
Interesting about moisture and motor brushes. I never knew that. I
guess that helps explain why the brushes in my Zappy motor look
practically new after 400 miles despite being run at over 4X the design
power.
If it turns out to be true (a 'discovery') that great excess of
humidity actually aids commutation, great!
I should be able to do some rough-and-ready tests to "prove" the
hypothesis further:
If, on a dry day, the motor runs hotter--I can dampen the blower's
airstream by wetting the filter foam. Continue running just the same.
If motor temp begins to drop: proof that more than a mere trace of
water is wanted for best commutation. AND proof that a totally enclosed
brushed motor is a bad, bad proposition.
IF that's so *not likely to bear out in testing, alas*, we will have
taught the world of totally enclosed brushmotor makers
a valuable lesson.
Perhaps Howard Penrose at the Maintenance forum will have a direct
answer to this...
burning question.
NB: do not take out-loud thoughts too seriously;
although I -think- I see a solid trend/effect,
more testing is needed.
Rhetorical question: what is the available water vapor in a closed
brushmotor at, say, 100C operating in Arizona on a summer day? Not
much! Not like my COOL motor saw this AM on the quarter mile track.
Damp morning air; I never liked the feeling of damp so much as I do
today.
____________photo by fechter:
http://img156.imageshack.us/img156/3286/fechtersb1.jpg
This is fechter's cooling job from which I drew my plans.
Note that it is surely superior in air delivery
on account of larger, shorter hose,
and probably having more pass-through holes in the motor.
Yet his is a smaller blower by far.
Posted by: Reid Oct 12 2006, 02:57 PM
it's a rainy day
http://imageshack.us
Despite the noise factor of motors with spur gearing
I've come to like the Currie system for its neatness.
The extra freewheel--the left side freewheel of the special Currie rear
hub is silent running.
It does not click click click like the conventional freewheel on the
other side of this same hub.
Why is that? Say,
wouldn't it be nice to have a world of silent pedal bikes?
All bicycles I know click click click when the rider coasts.
http://img149.imageshack.us/img149/4227/screenshot076dm4.jpg
...have yet to shroud the air exit holes.
a rainy day perspective...
thanks for having a good day
despite personal difficulties we all live with;
very small troubles they surely are
for we who have time to play with our toys
Posted by: Deafscooter Oct 12 2006, 03:43 PM
Deafscooter have many Small Blower to cool the motor it much powerful
flow like hairdryer gun
It has fully ballbeaing on motor and heavyduty brush for long life time
and it run on 24 volts DC
the nozzle dia is Exact 7/8 Inches the Centrifugal is turbine 3 inches
Rotor, house is 4.5 inches
are you intertesting to buy the Centrifugal fan for your need to
project or need to cool the motor.
For asking price each on Fan --- Call ==>> Deafscoo...@yahoo.com
Thank for Visit this Picture .........
Here is Picture of 24 volts Centrifugal Blow Fan => You measure theFan
on Yellow Ruler as size
http://www.visforvoltage.com/forums/uploads/post-22-1160682205.jpg
Attached Image
Posted by: Reid Oct 12 2006, 04:49 PM
Well, we can always count on Craig for free enterprise!
Sell me one for review/promotion purposes...
...for free?
I see it's ancient, high quality N.O.S. Xerox copy machine stuff.
This'd be a fine blower for my bike;
retro rules.
What is the static pressure produced, Craig?
Can you do a U-tube manometer test, please?
Please determine the no-flow pressure, expressed in inches of water
lift, at 24V.
It's very simple:
http://www.dwyer-inst.com/htdocs/pressure/ManometerIntroduction.cfm
use any gauge of vinyl tubing, tacked to a board with ruled markings.
http://img517.imageshack.us/img517/2972/manometerintro1picte5.gif
If it is better than my blower (which I have not so-tested yet),
I would like to try one of your blowers.
Let me know here, in public, OK?
What is your selling price?
Thank you,
Reid
Posted by: Reid Oct 12 2006, 05:05 PM
A reader sent me an email through the Voltage forum's system.
Not sure how to reply to that...whether it would go to him or bounce
back
from the V system only. It is a question of wide interest to owners of
the old
Currie add-on system.
QUOTE
hi there i have an old black 24v curry. going to give it 36v soon. any
tips. did u have black one first or something else? thanks Michael
London
No, I have had only one Currie bike and it is of the current crop,
similar in the basic drive (motor hangs off the rear hub).
Otherwise, the only similarity is the reported fact that you'll fry its
motor
if you run it hard on 36V.
Am sure you can run it on 36V if you force cool the motor.
I think it'd be much easier to cool a brushless motor than a brushed
motor.
Too bad we have not yet figured a way to cool hub motors by air draft,
not without opening it to the elements.
"We" means VisForVoltage members.
This is a team effort after all.
Cheers,
Reid
Posted by: Buzzz Oct 12 2006, 05:19 PM
Don't really need to force cool just about any brushless hub motor i've
heard about as overheating them is just about impossible without insane
measures imposed.... ie: 100v x 40 amps x Time.... I manage to get mine
warm to the touch / slightly hot at 1000w + constant ( off-road does
this !! )
Posted by: Reid Oct 12 2006, 06:06 PM
Ah, but small hub motors have reportedly burned up if overstressed.
You're speaking of super duty hub motors, aren't you?
I mean, there are more anemic hub motors out there than husky ones.
___________________
Allow, please, a few minutes for human interest digression, non
fiction,
because this biking activity leads to our meeting people:
Just last night, on the return home from testing the bike at the H.S.
track,
passing the Amoco gas station,
"Hey!"
It was Harris hailing.
Harris (not his real name) is a 46 year old black man, self-admittedly
drug addicted.
He has only a shambling old bicycle to his name. I met Harris last week
when he politely asked, outside the conveniece store across the street,
whether
I might have any spare change. We chatted. "I'm so broke. I just had to
put new
wheels on the bike. The bearings were all falling out."
He's gentle and resigned.
This AM he mentions that he needs brake pads for the bike.
"I'll give you a take-off set from mine.
But since I don't see you regularly, how can I get them to you,
Harris?"
"Well, there's a spot over behind the Dumpster behind the store."
I followed him over there to the Dumpster.
"You could put them in that hole in the broken wall. I'll find them."
While we were there he opened the Dumpster.
I am holding the lid up now while Harris inspects.
He's got his hands in the garbage.
"Man, how can you do that?"
"That's what soap and water are for."
Harris is clean. He lives nearby with his aged parents.
"It's amazing the stuff people throw away.
Just the other day I got a TV and a VCR player and they worked.
I found a six pack of El Presidente beer. One time I found one of those
inflatable dolls---you know what I mean?"
"Yes, I've seen ads..."
" I traded that to the Panamanian clerk inside the store
for some food and stuff. And so that was a good deal. People waste so
much."
Harris is no philosopher. He's a poor guy lucky enough to have parents
who keep him under roof. He gets a few bucks and does his thing.
He doesn't harm anyone. His eyes are sad.
"My stomach hurts today. I have an ulcer. Do you have any cigarettes to
spare?"
I had no money on me at all. I had no cigarettes either. He asked for
no money.
He was delighted that I have unneeded brake pads.
"I guess I'd better ride on over to the other gas station now."
I joked (I thought): "Don't ride too fast, Harris" (my bike--with an
electric motor)
"No, I can't ride fast anymore at all." he replied without any trace of
irony.
Good night, Harris.
"Good bye"
__________________
----One hundred years ago Harris had a counterpart.
What follows is a poem that I'll read to you folks,
then its back to shallower topics
such as my selfish personal interest in ebikes.
__________________
A Vanished Calling
very slowly
recited by author/me
http://tinyurl.com/s35o3
A rag man re-
arranged his shuffle
-must look smarter
for rich Mrs. Doudy.
"Any rags today kindly Mizz Doudy?"
"My oldest silks
are too fine
for you."
"Thank you 'for you'
thank you Mizz Doudy."
A rag man re-
arranged his shuffle-
no one to-day adds cloth to his duffle.
He turned to rundown
lackaday lane-where no flowers
grow where a rag man has lain
long under stars-
stirred only by sweeps-
his fibers are rag pa-
per faintly inked
-it is here that he
weeps over all
and forever.
Posted by: Dart Man Oct 12 2006, 06:08 PM
Hey Buzzz, what was the outside temperature though, don't you live up
by the north pole?
Don't you get snow?
Posted by: Reid Oct 12 2006, 06:21 PM
Yeah! BUZZZZ, (Mr. Freeze)
we want to know...
ambient temperatures count for something, ha hahhhh!
Frostbite at the least.
Posted by: Nickf Oct 12 2006, 06:59 PM
Reid,
36 volts in a standard brushless currie motors is, as far as i know, a
very bad idea. The controller is inside the motor so it may be damaged
by heat, also the fets are, so I'm told, only rated for 30v.
Peeps run at 36 volts by using an external controller with a specailly
rewired currie motor. I was lucky enough to have someone make one for
me, but they can also be brought from http://powerpackmotors.com/
I think it might be cheaper to do it your way. how much is the unite
motor? and will it fit into the old USPD (spoke clip on) drive?
Good to know about the temp that neo magnets degrade I'll have to be
careful of temperature. Knoxie had a cut out at 48 volts and thats what
i'll be running at soon, with a bit of luck.
Very sad poem, but well read. You can tell its real poverty when people
are really happy to get stuff like used brake pads!
Funny just been watching a vid thats kinda related,
http://video.google.co.uk/videoplay?docid=7875774574550696048&q=rober...
Posted by: Buzzz Oct 13 2006, 09:58 AM
Lol... you guys crack me up.....
Yes.. we get winters and snow and - 40 celcius around these parts.. but
during these 3 or so months .. i park my bike and battery pack inside
my cozy igloo !!
Summer months are quite hot.. ( well .. i would call it hot.. some of
you would laugh at the idea of 30 celcius i guess. hehe ) but during
peak summer, i've used and abused both my WE and my c-lyte hubs and
have not yet gotten a controller cut-out or motor failure or even got
close to burning my hand on my motor..
I guess if you rode in the desert up hills full throttle with the
brakes on.. yeah.. you would probably need forced air cooling somehow..
Posted by: csaudio Oct 13 2006, 01:53 PM
Buzzz
I burned up two of the Crave Chopper brushless rear hub motors. They
are advertised as 24v 450w. The first one burned up at 36v. The second
one burned up at 48v. You might think I would have learned with the
fist one, but no, sure didn't.
Neither one smoked, just gave up with a whimper.
Posted by: Reid Oct 13 2006, 06:23 PM
Same as with the first Unite! There was neither smell nor smoke, it
being sealed.
It whimpered (perfect word!) to a final stop.
______________
Buzzz as a young WC Fields:
http://img521.imageshack.us/img521/9817/fields10nh2.jpg
Reminds me (funny) of a W.C. Fields movie.
Fields, in a Yukon cabin, opens the door to survey the great white howl
outside.
Dramatically, with stage histrionics, gravely intoned for comic effect:
"T'ain't a fit night out for man nor beast."
Pause. Then he gets a face full of stage snow.
Subsequently, through the film, every time Fields opens the door again,
(dramatically)
"T'aint a fit night out for man nor beast."
Again, an absurd pause.
Fields gets whalloped with obviously fake snow.
__________
Buzzz as Fields, or is it Fields as Buzzz?
up to date and in context
"T'aint no way a hub motor burns"
Pause. A racing bike plumes dense blue smoke.
________________
Fondly kidding,
r.
