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Broderick
11-21-2002, 10:30 AM
Im trying to find more information on the crush zone designs that Cornell was running in preavous years. It looked like circle that was punched out but their was a lip that went in, instead of just a circle. I heard it might be called swauging(not sure about the spelling) or something like that. Sorry for the vagueness.

Broderick

Broderick
11-21-2002, 10:30 AM
Im trying to find more information on the crush zone designs that Cornell was running in preavous years. It looked like circle that was punched out but their was a lip that went in, instead of just a circle. I heard it might be called swauging(not sure about the spelling) or something like that. Sorry for the vagueness.

Broderick

Michael Jones
11-21-2002, 03:00 PM
Yes the last two crushables had indented holes, as you describe...the logic being that this is stronger than a simple hole...most of our testing was done on alternative designs, with this one being a fallback - a very simple box for a very vague rule that requires little.

As for the process, it's decidedly low tech. Drill a hole, find a cone slightly larger than the hole, hit cone through hole. Dunno if that merits a special name, but it's fun and gets acceptable results with some post-smashing filing.

Hope this helps.

Richard Lewis
11-21-2002, 08:55 PM
This is one rule I'd really like to see modified... these crush zones are a joke from a good 90% of the teams out there. (ours included) Is there anyway to quickly test these at the competition without crashing the car?

-------------------------
UVIC Formula SAE Team
http://members.shaw.ca/drax77/UVICFSAEcar.jpg
http://fsae.uvic.ca

zorr0
11-22-2002, 09:02 AM
This process is called flaring. It does make the structure stronger and more rigid than an identical structure with a plain hole. Done correctly, two conical (one convex, one concave) are pressed against the sheetmetal. These dies are a PITA to make.

http://www.auburn.edu/~zornmat/eagleside.jpg

]http://www.auburn.edu/~zornmat/pics/img_0399.jpg] (http://www.auburn.edu/~zornmat/pics/img_0399.jpg)

Michael Jones
11-22-2002, 10:58 AM
...agreed with Richard that the crush zone rules leave a lot to the imagination, and it shows. We attempt to put on something that isn't fundamentally retarded, but the letter of the law suggests a helium balloon of the right size would be perfectly OK. 2002 rules suggested that the 2003 rules would change to specify a minimum requirement. Guess they didn't get around to that.

Testing on site is certainly destructive, and would require that teams build multiple crush zones. But showing evidence of testing is certainly understandable. We've crushed various iterations of the Al box over the last couple of years, and our prototype crushable last year (not used due to packaging and manufacturability concerns...and the fact that it ripped pants on a regular basis and ticked people off) was backed up by decent theoretical and crush analysis.

Flaring, that's right...although I like the banging cones through holes process more. Wholly improper but way fun.

[This message was edited by Michael Jones on November 22, 2002 at 06:29 PM.]