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Unread 06-07-2014, 12:31
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Re: pic: Off-Season Drive Project

Quote:
Originally Posted by AdamHeard View Post
Using a bolt to retain the wheels and take up all slop is a bad idea as it will preload the bearings. It's also more likely to loosen the fastener.
Compared to two snap rings, etc. it's definitely sub-optimal, but with regular maintenance (check the bolts before a match) and some Loctite, it's a decent enough solution that will retain wheels and account for manufacturing tolerances. Just don't over-tighten the bolts as the tighter they are, the more preloaded your bearings are, and hex bearings seem to be particularly temperamental in FRC.

By the way, the wheels in 11's photo are 2" wide black Colsons.

I'll third the notion of not using thin polycarbonate as a structural belly pan. Polycarbonate is great for some applications but in this one the thickness you need for polycarbonate to be sufficiently rigid makes it a poor choice compared to thinner sections of other materials, such as garolite. We still use an un-lightened 1/16th aluminium belly pan though this is suboptimal.
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Last edited by Chris is me : 06-07-2014 at 12:33.
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