recumpence
1 GW
AussieJester said:
I don't see any reason why not, either.
Matt
A picture's worth a thousand words....... (title edited)
- Thread starter recumpence
- Start date
I don't see any reason why not, either.
Matt
MitchJi
10 MW
Hi Matt,
Have you talked to Pfeifer Industries (your neighbors). They can help you get at least 5.38:1 (26t/140t).
Can you use a smaller drive sprocket, something like 20t or 22t or 24t?
http://www.pfeiferindustries.com/capabilities.htm
Sweet!recumpence said:
Have you talked to Pfeifer Industries (your neighbors). They can help you get at least 5.38:1 (26t/140t).
Can you use a smaller drive sprocket, something like 20t or 22t or 24t?
http://www.pfeiferindustries.com/capabilities.htm
http://www.pfeiferindustries.com/contact.htm
recumpence
1 GW
Yes, they are the ones who made this pulley.
I could not even imagine what a 140 tooth pulley would cost. but, if I had to hazard a guess, I would think it would be in the range of $400 to $500 for one pulley that large. They have the capability to make pulleys larger than this, but they do not stock material to go that big, and I do not think they have ever made a pulley that large for a customer.
It is not big deal, though. The majority of my customers run 3 to 1 from jackshaft to the rear wheel.
Matt
I could not even imagine what a 140 tooth pulley would cost. but, if I had to hazard a guess, I would think it would be in the range of $400 to $500 for one pulley that large. They have the capability to make pulleys larger than this, but they do not stock material to go that big, and I do not think they have ever made a pulley that large for a customer.
It is not big deal, though. The majority of my customers run 3 to 1 from jackshaft to the rear wheel.
Matt
My God, that thing is incredible! I just saw the video, Man, does that thing... just... go! I'm so much more excited to get my setup working!!!
For the big Cog:
I tried the epoxy thing (using the belt as a mold to put teeth on a round blank) for a small robot I was doing, and the teeth stripped off.
I have no way of knowing why the teeth failed, but if I had to guess, I'd assume it was because the epoxy was too brittle, and too few teeth were engaged.
Why would custom jobbers make the cog out of round? It only looks about 3/4 thick or so. Why not use plate? Certainly much easier to get in whatever size you want.
Every time I look at those cogs, I see that the tooth valley is round at the bottom. Then I wonder, what if I laid out the holes very carefully and drilled...
Probably a terrible idea... Right?
Katou
For the big Cog:
I tried the epoxy thing (using the belt as a mold to put teeth on a round blank) for a small robot I was doing, and the teeth stripped off.
I have no way of knowing why the teeth failed, but if I had to guess, I'd assume it was because the epoxy was too brittle, and too few teeth were engaged.
Why would custom jobbers make the cog out of round? It only looks about 3/4 thick or so. Why not use plate? Certainly much easier to get in whatever size you want.
Every time I look at those cogs, I see that the tooth valley is round at the bottom. Then I wonder, what if I laid out the holes very carefully and drilled...
Probably a terrible idea... Right?
Katou
recumpence
1 GW
The pulley is 1.1inch thick. It can be made from plate. But it would still cost alot.
Yes, it really moves out. It is geared for right at 40mph with a full charge. It gets there in about 4 seconds.
I hope to make a newer style, updated reduction unit with a lower ratio to allow high KV motors to be used with this final drive ratio. Again, I need to say, 3 to 1 is what most people are running anyway.
Matt
Yes, it really moves out. It is geared for right at 40mph with a full charge. It gets there in about 4 seconds.
I hope to make a newer style, updated reduction unit with a lower ratio to allow high KV motors to be used with this final drive ratio. Again, I need to say, 3 to 1 is what most people are running anyway.
Matt
E-racer
1 kW
I have made large sprockets before with no cnc equipment relatively quickly and easily. You simply cut a disk the proper diameter for the number of teeth you need. I usually manually lathe aluminum but plastic would probably work out well. Prep the outside diameter of your disk for epoxy. Then cut a piece of timing belt to the number of teeth you designed your pulley to be. Coat the belt in mold release, then cover the belt in epoxy. Wrap the belt around the disk you made. let this dry then pull the belt off to reveal your custom teeth. I've had great success with this process. If I decide to go belt on my e-bike I'll be making one of these. I think I'm going to try to make one with carbon layed in the belt before I apply epoxy. Carbon teeth on a lightweight billet hub would look killer.
Kurt
10 kW
Looks and sounds great,
Quiet, strong and low maintenance. Not to mention neater Without the need for a chain tension idler. I am looking at a single stage reduction drive for my new Turnigy 80-100 powered trike project. If You put this new belt system into production it will be on my shopping list.
Kurt
Quiet, strong and low maintenance. Not to mention neater Without the need for a chain tension idler. I am looking at a single stage reduction drive for my new Turnigy 80-100 powered trike project. If You put this new belt system into production it will be on my shopping list.
Kurt
recumpence
1 GW
Yes, this will be put into production.
I am picking up the remaining three prototype kits today or tomorrow. Two are spoken for by Tommy from FFR trikes. So, I have one available. I was hoping to install it on either my Catrike or my Dahon folder. But, I am willing to sell it. I am confident that no more testing is needed to assure it is a good, solid assembly.
The only issue with production is, I need to order 10 kits at a time to keep the cost out of the stratusphere. So, I will take request for them. Once I have 4 or 5 requests, I will order 10 kits.
Bear in mind, these are not like Astro motors. There is precious little wait time. This shop turns orders around lightning fast. So, if anyone wants a kit (aside from a wait time to compile a few orders), they will be produced quickly.
Matt
I am picking up the remaining three prototype kits today or tomorrow. Two are spoken for by Tommy from FFR trikes. So, I have one available. I was hoping to install it on either my Catrike or my Dahon folder. But, I am willing to sell it. I am confident that no more testing is needed to assure it is a good, solid assembly.
The only issue with production is, I need to order 10 kits at a time to keep the cost out of the stratusphere. So, I will take request for them. Once I have 4 or 5 requests, I will order 10 kits.
Bear in mind, these are not like Astro motors. There is precious little wait time. This shop turns orders around lightning fast. So, if anyone wants a kit (aside from a wait time to compile a few orders), they will be produced quickly.
Matt
bobc
10 kW
I would try water jet cutting to make the big pulley - any size you like then......
A large 25mm thick pulley is going to cost quite a bit in material, but you can get at least some of that back by water jetting lightening holes into it. I would expect the water jet resolution to be good enough for a toothed belt,- in my experience it is very comparable with laser. I got some gearbox casings water jetted & 260x320x20mm was about £30 ($50)
If you put Nx3 lightening holes (let's say 6) you'll be able to hold the pulley in a sensibly sized 3 jaw chuck for finishing on the lathe.
PS - you'd be worried about the very slight angle that water jet cutting can put on the cut edge. get round that (if it turns out to be an issue) by making it 0.1 to 0.2mm oversize & finishing square on the lathe with a single light cut. (make the nobble cuttouts right obviously....)
A large 25mm thick pulley is going to cost quite a bit in material, but you can get at least some of that back by water jetting lightening holes into it. I would expect the water jet resolution to be good enough for a toothed belt,- in my experience it is very comparable with laser. I got some gearbox casings water jetted & 260x320x20mm was about £30 ($50)
If you put Nx3 lightening holes (let's say 6) you'll be able to hold the pulley in a sensibly sized 3 jaw chuck for finishing on the lathe.
PS - you'd be worried about the very slight angle that water jet cutting can put on the cut edge. get round that (if it turns out to be an issue) by making it 0.1 to 0.2mm oversize & finishing square on the lathe with a single light cut. (make the nobble cuttouts right obviously....)
recumpence
1 GW
The problem with water jet cutting is there is no way to machine the back side of the pulley for the proper recess though you maybe able to get the tooth profile even still I would be worried that the belt wouldnt track properly.
E-racer
1 kW
You could always stack a set of water jetted plates, much like a stator is constructed. Then you can just use one plate as the hub. 1/8 plate is cheap or you could go plastic (maybe aluminum hub and the rest of the plates plastic :-D). With thin stacked plates you don't have to worry about kerf angle. Then you could just wrap a belt around it to constrain the teeth. I would definitely bond them with epoxy.
Hillhater
100 TW
E-racer said:
Since the polychain is 8 mm pitch, you might also consider the above idea but using a "stack" of readily available 8mm or #219 chain sprockets
It may be necessary to "trim" the top of the profile, but it may just work ?
recumpence
1 GW
That is still not nearly enough offset however. The pulley actually needs to be dished to the side quite a bit.
j3tch1u
10 kW
recumpence said:This is Ben's bike.
http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=15233&start=390
I have ridden the trike a few miles. It is nearly totally silent. Under acceleration, you can hear the motor whine. But, when up to speed, all you hear is wind and a tiny bit of belt sound. It is very cool! It runs sooooo smooth. I am very happy with it. I am also happy with the Sprague one-way rather than a freewheel.
I do have a video of it. I need to upload it to youtube so I can link it here.
Matt
noooo....i didn't think you meant me. i think first prize should go to HAL! the man builds robotic fabs for a living!
very tight build matt--another home run! you have sold me on the conti's (and have thus set me back another month in development haha). now, do they come in Ducati red teeth?
what # sprags are you using and did you have to do any machining to them?
i'm trying out double 15mm ID sprags welded together and threaded on the outside...but after seeing this, i've decided to go with inner-sprag / outer sprag / pulley instead for my dual freewheel setup.
E-racer
1 kW
That design could be tweaked. You could also run a hub to get w/e offset you want. I cant argue though I love nice CNC pieces to!recumpence said:
northernmike
10 kW
Next step = custom hub / wheel.
With the pulley size approaching 2/3 the rim diameter, 2/3 of the spoke length on that side seems redundant, doesn't it?
Could the pulley and hub not be one piece?
Perhaps the "printing" technology Miles brought up the other day could facilitate?
If not, could it not be attached like so?
With the pulley size approaching 2/3 the rim diameter, 2/3 of the spoke length on that side seems redundant, doesn't it?
Could the pulley and hub not be one piece?
Perhaps the "printing" technology Miles brought up the other day could facilitate?
If not, could it not be attached like so?
recumpence
1 GW
I have looked into pulleys and sprockets attached to the rim. I like the idea alot and almost went in that direction. The only reason I did not is freewheeling. With a pulley that large, the countershaft freewheel/sprague would be spinning really fast when coasting. That would kill motor-off pedaling. But, I love the idea........
Matt
Matt
recumpence
1 GW
Here are some finished pics.
The disc brake caliper needed to be milled narrower (the back plate) to clear the pulley. But, it clears (barely).
The trike is very well finished right now. The only thing left is to replace my one pack with a bad cell and get my Zivan 1500 watt charger!
It runs like a champ. The motor runs at 125 degrees F with aggressive driving and much cooler cruising. It runs nearly silent and maxes out at 42mph hot off the charger and 40mph for most of the pack after that. It pulls pretty hard considering it is setup for mild sport driving, not the top-fueler setup it was running previously.
The only "Problem" I am having with it is front brake rotor vibrating. I have tried many cures. I think I will go with floating rotors (Hope brand). That will eliminate the resonance because of the two piece design.
Enjoy the pictures!
Matt
The disc brake caliper needed to be milled narrower (the back plate) to clear the pulley. But, it clears (barely).
The trike is very well finished right now. The only thing left is to replace my one pack with a bad cell and get my Zivan 1500 watt charger!
It runs like a champ. The motor runs at 125 degrees F with aggressive driving and much cooler cruising. It runs nearly silent and maxes out at 42mph hot off the charger and 40mph for most of the pack after that. It pulls pretty hard considering it is setup for mild sport driving, not the top-fueler setup it was running previously.
The only "Problem" I am having with it is front brake rotor vibrating. I have tried many cures. I think I will go with floating rotors (Hope brand). That will eliminate the resonance because of the two piece design.
Enjoy the pictures!
Matt
Attachments
Kurt
10 kW
That front chain ring looks as big as the 16" front wheels! Huge front chain rings are a visual statement saying FAST. A bit like when you see a supercharger poking out of a car bonnet.
I have the same issue with front rotor noise, left hand side is worse. It doesn't effect braking performance but is annoying and gives a cheap feel to things.That torque arm from the reduction drive to the rear drop-out. I take it there is a bearing on the jack shaft end hard to see from the pics?
Kurt.
I have the same issue with front rotor noise, left hand side is worse. It doesn't effect braking performance but is annoying and gives a cheap feel to things.That torque arm from the reduction drive to the rear drop-out. I take it there is a bearing on the jack shaft end hard to see from the pics?
Kurt.
recumpence
1 GW
Kurt said:
Two bearings side-by-side.
Matt
flyinmonkie
10 kW
Awesome Matt, what else is there to say. The pictures really don't do it justice. It looks so much better up close and in real life.
I like the belt final drive, very clean.
Clay
I like the belt final drive, very clean.
Clay
Hillhater
100 TW
recumpence said:
Have you tried reversing the rotors on their hubs ??
recumpence
1 GW
That is actually bad for the rotors. The way the center portion of the rotors is setup, that can cause the rotors to warp under hard braking. So, I have not tried reversing them yet.
I know it is a resonation issue, not merely a glazing problem. Before I replace the rotors, I will try adding a small amount of weight to each of the rotor center "Spokes". This will drastically reduce the resonant frequency of the rotors and should really help alot. If not, I am sure floating rotors will fix it. But, sheesh, I have spent sooooo much money on this thing. I need to just stop at some point and enjoy it.
Matt
I know it is a resonation issue, not merely a glazing problem. Before I replace the rotors, I will try adding a small amount of weight to each of the rotor center "Spokes". This will drastically reduce the resonant frequency of the rotors and should really help alot. If not, I am sure floating rotors will fix it. But, sheesh, I have spent sooooo much money on this thing. I need to just stop at some point and enjoy it.
Matt
Thud
1 MW
Also try a bit of the adhesive they hold pads to the calipers on auto stuff...the magnets on the bike stuff allow the pads to shake,rattle & roll.
(I use that on my rear brakes of all my CR's to keep em form squealing)
(I use that on my rear brakes of all my CR's to keep em form squealing)
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