Another cool 2spd Dog-box build

[boostjuice]

I happened to stumble upon this blog project using a Kollmorgan and a REALLY nice 2 speed dog box (oil bath sealed!). As far as I can tell this hasn't already been scooped, however knowing the size of the ES community, the builder is probably a member here :| Enjoy!

Parent blog >>>>>>> http://coppersnot.com/BikeTranny.html

 

[boostjuice]

His V1 build shows some nice/innovative machine work as well!

Parent blog >>>>>>http://coppersnot.com/Manufacture.html

 

[liveforphysics]

OMG.

Jaw drops.

Pants get tight in the front.

I have a fetish for dogboxes.

 

[AussieJester]

Very nice indeed, but why oh why waste such beautiful work on such a cheap ass bicycle :-| Luke, whats the go with aluminum dogs and sprockets wouldn't steel be optimal for wear? even considering they are in oil...

This just makes me wanna go pitch the tent out the front of my house so i don't waste a second getting my 2 speed dog box from the courier driver when he rolls into my driveway :wink: ...it could be here any day now...I is like a 8 year old on Christmas eve that knows he's getting a bike from Santa hahaa

KiM

 

[boostjuice]

It looks to me that the dogs/sprockets are made from steel judging by their colour. Kim, what makes you think they are aluminum?

I agree about the Walmart/Kmart bike not being the best foundation for custom machining of this caliber.

A gearbox of that strength/quality deserves more than a mere Kollmorgan pushing through it as well

 

[liveforphysics]

Well, KiM, under normal conditions, an aluminum dog would definately be a wear/failure issue just waiting to happen. From the looks of it, he sized this to equal the dog width, depth, diameter of what they run in vehicles with >1,000hp, so in practice it likely won't be a concern. Super over-building can make up for less than optimal metalurgy choices in this situation.

 

[amberwolf]

Made his own freewheel, too. 8) The pictures of the machining are very helpful...when I get around to redoing the CB2 drivetrain (or CB3 or whatever it ends up as), this will be useful.

 

[Hillhater]

Made his own freewheel, too.

Obviously has more time (& skills) than money ! :lol:
.. but making a complete freewheel is a little extreme !.

surely he wouldnot spend all that time machining and only use Al for the gears /dogs ? .. they must be steel !

 

[liveforphysics]

This is my tranny:

In first gear, this is holding over 1,200ft-lbs of torque on the counter-shaft.
I think his aluminum dogs will be just fine with a little 250w currie or whatever he is running on that bike. lol

 

[Hillhater]

Its not so much the strength, but the wear, and "gauling" that Al suffers from
If you are going to go to all that effort to design and machine up a component, you make it from the best material for the job so it will last a while.

I am sure the freewheel components are not Al !

 

[Miles]

If you're worried about wear with aluminium, have the parts hard-anodised.

 

[boostjuice]

He's not an idiot. The load bearing parts are almost certainly steel. Look at the colour of them. They have a more grey/gold coloured tinge to them than the aluminum parts that have more of a 'white' hue.

Thanks for your pics luke. this thread is really turning into 'Dog-porn' (i wonder how long before this thread is flagged for inappropriateness)

 

[AussieJester]

Firstly i wasn't implying he was, there are certainly some steel parts, the ratchet being one, he says on his blog when refering to it and i quote " Aaaahhhh! It's steel! I don't like steel! It's so hard!!! - the dovetail screams... (taken by Bill Bailey)" The dogs and sprockets have an aluminium look to them in some of the pictures. Pitty there is no contact info on his blog :-(

KiM

 

[liveforphysics]

Its not so much the strength, but the wear, and "gauling" that Al suffers from
If you are going to go to all that effort to design and machine up a component, you make it from the best material for the job so it will last a while.

I am sure the freewheel components are not Al !

I can understand his reasons for going with Al, and choosing to over-size everything rather than using steel.

Ease of construction. I personally wouldn't have a snowball's chance at making the needed parts from a proper high carbon steel. Yet, when I think about aluminum, it suddenly becomes an exciting option for something I have the tools and means to construct.

If you're worried about wear with aluminium, have the parts hard-anodised.

I think proper tip design on the dogs with an agressive back-cut to ensure the collar draws up tight before taking any notable torque, and a properly done HA3 coating would give a service life that exceeds any reasonable criteria.

 

[Thud]

I don't see aluminum anywhere but the mounts, cases & maybe the shift fork. Sprokets look like stainless to me (redily available)
But wow! what a realy nice job. (makes my stuff look like junk LOL) I love to see what 1-offs these kids knock out with access to tools that 99% of the population doesn't have. Add that with some creativity & the skys the limit. I am totaly impressed. (& realize how lucky I am to have the tools to make the stuff I need).

KIm: throw your unit on a scale when it shows up. I forgot to get an all up weight fully assembled. Thx.

 

[liveforphysics]

If that's all stainless this guy machined... omg... uber-machinist skills.

 

[Thud]

LOL luke,
You can buy stainless sprockets right out of the McMaster Carr catolog. (like 4x the price of normal & 10x the price of my china bulk stuff) & 416 stainless (typicle gun barrel stock) machines really well. You would have no issue with it.
for sure though...that is a shiny tranny!

 

[AussieJester]

Shall do ThudSTeR hopefully tomorrow :: fingers crossed::

He bought the sprockets from http://www.recycledcycles.com/ perhaps someone local could call on Monday and ask what the sprockets they sell are made from?... My votes still aluminum sprockets, i thought they looked too wide for steel compared to all the #25 sprockets i have seen and have here anyway plus he states in his blog he 'hates steel' .. but i'm wrong alot in fact more often than not LoL :wink:

KiM

 

[liveforphysics]

& 416 stainless (typicle gun barrel stock) machines really well. You would have no issue with it.

You over-estimate my machining skills. lol. I sometimes manage to break tooling and FUBAR parts doing soft plastics and doing 4000-series T-0 aluminum. lol

 

[Thud]

I hope you don't scare the postman shreiking like a 3 year old girl kim when the package arives. :lol:

I assume he bought the bike chain rings from the re-cycle cycle place...the size scales to #25 from my viewpoint. I don't mind machining steel so much.....if it decent steel. some guys buy cheap hot rolled crap, that tears & galls more than cuts.
but for sure stainless is redily available (used in food proccesing equipment all over) I think I i remember seen some shiny steel sprockets on matts PKripper. (but that doesn't mean they were stainless per-say).

 

[AussieJester]

I hope you don't scare the postman shreiking like a 3 year old girl kim when the package arives. :lol:

I would say the chances are better than good I will ThudSTeR :lol: I all but rugby tackled the courier driver that bought my Turnigy From HK as the box looked like it was about the right size to be the 2 speed box not just a motor haha...Can't be far away

KiM

 

[knoxie]

8)

Nice work!! really nice and yes that kol motors power will all but disappear by the time it hits the rear wheel, with the stock controller they are underwhelming, rip out the controller and run them on an external controller and they run great and he can keep the RPM down as he is using his gearbox, one thing those motors dont like is extended runs at 48V and upwards, the rotor magnets have a habit of cracking and flying off, been there done that.

I managed to pick a box of 6 of those motors a few years ago still got them in the loft and intend to use one with the stock controller to make a little car for my young son, so yeah I think he may look at changing the motor and the bike.

 

[kevo]

Pitty there is no contact info on his blog :-(

KiM

AJ,
His resume page indicates coppersnot@gmail.com.

 

[AussieJester]

Pitty there is no contact info on his blog :-(

KiM

AJ,
His resume page indicates coppersnot@gmail.com.

Cheers mate missed it, i have flicked off an email to the fella, have asked if he can confirm the
metals used and also invited him to join the forum. Shall report back when/if i get a reply.

KiM

 

[kevo]

I'm wondering if he would allow Birdwell Machine to sell this based on his design, or better yet open source the CNC code!