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Unread 09-05-2010, 18:34
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AKA: Steven Greco
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Re: pic: 2228 Cougar cut on to sheetmetal (CAD)

Quote:
Originally Posted by 548swimmer View Post
If you have access to a vinyl cutter, that would be the way to go for this. 1/32 seems a bit small, but I'm not really sure. We tend to keep our walls at least 1/4, though for these parts structural integrity is an issue too. As far as other methods, no. Water-jetting will give you the cleaner edge than plasma, and a more reliably straight cut. With plasma, the edges are jagged, and may accidentally cut through a 1/32 wall. I think the wall thickness may be dependent on the precision of your water-jet, so I'd look for those specs if you can find them.
1/4 inch is overkill. My team used quarter inch side plates this year. We had 4 of them spanning the whole side of the robot and they were 3.5 pounds each after being cut and wouldn't break no mater what you did to them. CAD analysis I've done says 1/8 (if properly mounted and secured) should survive all FIRST type collisions. 1/32 is thin, but if it's just a backing for decoration it's not a problem. My team made our shooter in 09 purely out of 1/32 inch sheetmetal. It was really light and we had no structural problems (it didn't take any impact either though). For cutting it depends on the machine. Some might break it by accident, good ones won't. Any real machine shouldn't if used properly. The abrasive sand in waterjet can vary in tolerance and even abrasiveness, but it shouldn't shouldn't break a 1/32 inch piece of aluminum by accident. It can also depend on the PSI, waterjets PSI can vary by a couple 10 thousands. It can easily be adjusted to suit the material and its thickness.

Last edited by sgreco : 09-05-2010 at 18:42.
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