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Unread 09-04-2012, 14:24
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Madison Madison is offline
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Re: Tube Versus Channel

Most of our machines are made from 1x1x.063 aluminum tube and 1/8" polycarbonate gussets that are fastened together with 1/4" rivets.

1/4" rivets are definitely overkill, but they make prototyping with 1/4" hardware and swapping in rivets at final assembly a cinch and our laser cutter doesn't always do such a great job when cutting smaller holes into some thicker parts -- a #10 clearance hole in 1/2" material gets pretty oblong by the end.

This year's drive pods were built from aluminum standoffs and 1/4" delrin plate; I was a bit worried about how well the plastic would handle side-loading, but it's been a champ so far.

With respect to tube vs. channel -- in almost all cases, I'd use tube if I could. Tube is much stiffer than channel in torsion.
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