Where to get 20 tooth sprockets for plaction wheels
 

Does anyone know where I can find 20 tooth sprockets that will fit on Andymark's 4 inch plaction wheels? I've looked for a while, but haven't found anything.

Thanks!

EDIT: It's #35

Re: Where to get 20 tooth sprockets for plaction wheels
 

I think you'll run into a problem with the chain contacting the hub, if you try to use that small of a sprocket. 22 is about as small as you can go, isn't it?

Re: Where to get 20 tooth sprockets for plaction wheels
 

Really? Huh. That limits us a bit. Now the only other option is either more gearing down through sprockets, or getting a double sprocket larger than 15 teeth.

Re: Where to get 20 tooth sprockets for plaction wheels
 

You could go ahead and use Mcmaster here: http://www.mcmaster.com/#roller-chain-sprockets/=fu73t2

You could take their CAD drawings and just edit the bore to fit your needs? sounds solid cuz they already have all the sprocket part done correctly and just export it to a machine shop

Re: Where to get 20 tooth sprockets for plaction wheels
 

It's kind of difficult to drill the standard robot 6 hole pattern into sprockets like that. Using sprockets from AndyMark or VexPro sure is handy.

Re: Where to get 20 tooth sprockets for plaction wheels
 

Yeah your right, but what do you think about having a machine shop making one? Just asking cuz we were hoping to do that, but is it possible? :/

Re: Where to get 20 tooth sprockets for plaction wheels
 

Would it be viable to add an extra stage of gearing to the wheels? Like another stage between the gearbox and the wheels?

Re: Where to get 20 tooth sprockets for plaction wheels
 

What are you trying to do? make the robot go faster?

Re: Where to get 20 tooth sprockets for plaction wheels
 

We are at 10.05 fps, and want to go around 12 fps.

Re: Where to get 20 tooth sprockets for plaction wheels
 

And you can't find a larger sprocket for the transmission?

Re: Where to get 20 tooth sprockets for plaction wheels
 

We're using CIMple boxes, so that's 12 tooth pinion gears on CIMs going to a 56 tooth output gear which runs a 15 tooth double sprocket, going to "x" tooth sprockets on the wheels, where "x" currently is 22 or 24.

We can't change the gearbox itself, so we either need a larger double sprocket to mount on the CIMple box output shaft, or smaller sprockets to go on the 4" AM plaction wheels.

Re: Where to get 20 tooth sprockets for plaction wheels
 

And you're stuck on using 4" wheels?

Re: Where to get 20 tooth sprockets for plaction wheels
 

or you could find 2 half inch bore sprockets with a key way (you could add that if you really had to) thin enough so that 2 would fit on the output shaft back to back.

Re: Where to get 20 tooth sprockets for plaction wheels
 

Yes.

Re: Where to get 20 tooth sprockets for plaction wheels
 

Hmm. That... Could work.