Re: #25 Chain Drive Experience ???
 

AM used to sell thicker sprockets with a chamfer. Now they are thinner with no chamfer.

-RC

Re: #25 Chain Drive Experience ???
 

Unfortunately I don't have a source for aluminum sprockets other than Andymark. I was just pointing out the change in quality in recent years.

These look interesting. Please let us know if you get pricing and availability. We tried using a large nylon sprocket from Mcmaster carr on our intake this year, and had trouble with the chain not engaging properly. The pitch seemed to be off for some reason.

This makes a lot of sense. Team 359 uses bike chain which is 0.5" pitch, but much narrower than standard #40 chain. I'd be curious to hear from them how much stretch they see (if any). My understanding is that bike chain is way stronger than #25, but lighter than #35. Unless you could adapt bike sprockets, you would have to make your own. Other than that, it seems to be a great compromise between #25 and #35 chain.

Rob

Re: #25 Chain Drive Experience ???
 

Sorry to pull up this thread again, but has anyone found a reliable source for chamfered #25 aluminum sprockets? Does anyone know about these RobotShop guys?

Re: #25 Chain Drive Experience ???
 

I've never heard of them, but I'd suggest checking McMaster-Carr.

Re: #25 Chain Drive Experience ???
 

Unfortunately, McMaster has never sold aluminum sprockets. (They're strictly steel/stainless and nylon.)

Re: #25 Chain Drive Experience ???
 

Sorry about that, missed the aluminum part of your post. It looks like many of the #25 sprockets on AndyMark are aluminum. Are they not chamfered, or the wrong size, or something?

Re: #25 Chain Drive Experience ???
 

Yes, AM changed their #25s at some point. They're now thinner and no longer chamfered, and we're having systematic issues with CNC notch defects. There was a bunch of talk earlier this month about it, but it was never resolved into a different supplier. We're currently looking either at fixing the bolt pattern and bore on the less expensive RobotShop ones or crossing our fingers and trying to lathe a chamfer on AM's thinner ones. Wondering if anyone found a different solution.

Re: #25 Chain Drive Experience ???
 

I've never ordered sprockets from them but I ordered a couple robots kits from them for work. The kits were backordered but other than that arrived fine and worked quite well. Just don't try calling their phone support, it's terrible.

Re: #25 Chain Drive Experience ???
 

Does anyone happen to know, off-hand, what the change in material thickness on AM sprockets was? I'm looking for the thickness of a sprocket with chamfer versus one without a chamfer.

Re: #25 Chain Drive Experience ???
 

I believe the new sprockets are .125" thick. I know they are waterjet.
I'm not sure however how thick the prior ones were.

EDIT: Sorry, I was talking about plate sprockets. Should have been more careful.

Re: #25 Chain Drive Experience ???
 

Waterjet?

There's no way they're waterjet, unless you're talking about plate sprockets. It would make absolutely no sense to waterjet the tooth profile then turn them down to create the hub.

Re: #25 Chain Drive Experience ???
 

I could believe that the larger plate sprockets are waterjet. As far as I know, the smaller sprockets with a hub are still machined, and still have a chambfer.

Re: #25 Chain Drive Experience ???
 

Is something wrong with the hubbed sprockets? I'd only had/noticed people discussing issues with the plate versions. (Type A for AndyMark)


And thank you, Andrew. We'll probably get one from them, then.

Re: #25 Chain Drive Experience ???
 

Oops. My bad. Poor reading comprehension on my part. Didn't realize which was being discussed.