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Unread 02-06-2014, 08:31
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JamesCH95 JamesCH95 is offline
Hardcore Dork
AKA: JCH
FRC #0095 (The Grasshoppers)
Team Role: Engineer
 
Join Date: Dec 2004
Rookie Year: 2001
Location: Enfield, NH
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Re: Weight Saving Techniques

Here's a little quip that has kept 95 underweight since I started as a coach in 2010: worry about the ounces, the pounds will take care of themselves.

Edit: *zips up flame suit* I don't like 'swiss cheesing' at all. It has some sort of appeal in FRC that I don't quite understand. It's not very strength-efficient and it takes a ton of extra labor to execute. When I see swiss-cheesing all I can hear in my head is: 'my designer didn't understand my strength requirements or my weight budget and decided to make me weaker by drilling holes in me than by simply remaking me out of thinner or less dense material.' I do not intend this in a condescending way, I used to swiss-cheese parts too, until that little voice popped into my head.

Edit pt2: here is a quick FEA I did of a swiss-cheeses 1x1x1/8 6061T6 tube (on the left) of nearly the same linear density as 1x1x1/16 6061T6 tube (on the right). The middle is fixed, and both tubes' upper surface as 100lbf applied to it. The Mises stress distribution clearly indicates that the 1x1x1/6 tube is experiencing about 1/3 the stress as the swiss-chessed tube. The thinner 1x1x1/16 tube is around 3x stronger than the swiss-cheesed 1x1x1/8 tube for the same weight. Keep that in mind the next time the 'thinner wall vs swiss-cheesing later' thought comes to mind, or when you think that cutting holes in the center won't affect it too much (looking at you MichelB)!

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Last edited by JamesCH95 : 02-06-2014 at 09:17.