pic: Better Sprocket Assembly with AndyMark Parts

[Rob Stehlik]

Originally Posted by DampRobot

Yeah, I'll echo what CalTrain is saying here. Seems like an interesting idea, but it looks like it has assembly/disassembly disadvantages. Although I don't like dead axle wheels, if I did, I'd probably just use the regular #10 screws that the wheels are designed for. If nothing else, they're easier to assembly, and you can replace them a lot more easily if they break.

True, this is slightly more difficult to assemble. It's not for everyone. But we liked how it kept things concentric and there was no chance of sheared bolts. The picture might be a little misleading since it shows the HiGrip wheel while we actually used 6" pneumatic wheels.

Originally Posted by DampRobot

On a separate note, those sprockets look poorly sized. With #25 chain, I would suspect that the smallest plate sprocket (32 teeth on AndyMark) would work just fine with 6" wheels. We ran roughtop 6" performance hex wheel with 16 tooth hex sprockets last year, and only ratcheted climbing the bridge. 60 tooth, or whatever you have here, looks like overkill.

Allow me to elaborate: We used the Cimple boxes last year because they were readily available. The student who designed the drivetrain was targeting a speed of about 9 ft/s. He found that for short distances, acceleration is more important than top speed. This dictated the rather large 48 tooth sprocket on the wheels to get the required reduction, since the Cimple box is only single stage.