pic: New wheel CAD [Archive]

CraigHickman

17-12-2007, 20:55

[cdm-description=photo]29409[/cdm-description]

Ben Piecuch

17-12-2007, 21:02

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

=Martin=Taylor=

17-12-2007, 21:07

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.

Cory

18-12-2007, 00:05

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

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

Nuttyman54

18-12-2007, 11:22

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

CraigHickman

18-12-2007, 17:43

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

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

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

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.

PhilBot

18-12-2007, 22:13

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?

lukevanoort

18-12-2007, 22:24

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?
Look on page 1189 of the McMaster online catalog.

PhilBot

18-12-2007, 23:16

Cool, thanks.

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

CraigHickman

02-01-2008, 20:29

Cool, thanks.

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

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.