pic: New wheel CAD
 

Re: pic: New wheel CAD
 

I'm sorry, did you say "way too heavy?" How light do you need to make your wheels? Even with a 6wd setup and a 0.5lb wheel, you're only saving 1.5lbs from your drivetrain over what you show here.

I think our wheels were about a pound each last year. Then again, we were concerned about machining time, and not weight. It would have taken twice the time on the lathe/bridgeport to take another 1/4lb out of each wheel... Not worth the effort for us, though YMMV. Good luck with the lighter wheel.

BEN

Re: pic: New wheel CAD
 

You could save even more weight by machining it out of polycarbonate instead of aluminum. It would also save a lot of time since feed-rates could be increased.

Re: pic: New wheel CAD
 

Our wheels weighed 0.23 lbs last year. granted they're 4" not 6". 1.5 lbs is a pretty significant amount of weight when you really start counting grams so to speak. Whether it's worth the time or not is another story

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That, my friend, is a gorgeous wheel! How many machining ops does this one take, and why did you decide to go with a 5 hole/spoke pattern instead of the standard 6?

I have the feeling I'll be seeing another sexy and competitive robot out of 114 again this year! See you at SVR

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Weight is everything. 1.5 pounds down low is 1.5 pounds of speed you can put into your scoring mechanism.

This one is a 2 op on the CNC. The rivet holes are all even mainly just for show. We actually just sort of drill them on with a power drill when installing the tread. It saves a lot of machine time, and cost.

The 5 pattern is far more stylish, and lighter. Besides, everyone else does 6 or 4, which is why I usually stick with 3, 5, or 7.

Re: pic: New wheel CAD
 

Hey...

I tried looking up blue nitrile tread on mcmaster but either got too much or too little, do you have a more technical name or part number for what you mean?

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Look on page 1189 of the McMaster online catalog.

Re: pic: New wheel CAD
 

Cool, thanks.

BTW how does the nitride compare against standard/gum-rubber in wear and traction?

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The Blue nitrile wears significantly less than the wedgetop (which I'm assuming you're referring to, right? the Brown stuff with criss crossed waffle-esque treading?), assuming you install it right. The reason ours doesn't wear nearly as much as others is how we attach it: rivets. When the tread is riveted at several points, it can flex and move, rather than immediately wearing as it would were it glued on it's entirety.