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Unread 26-09-2013, 23:59
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AllenGregoryIV AllenGregoryIV is offline
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AKA: Allen "JAG" Gregory
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Re: pic: Spectrum Fall 2013 Drive V2

Quote:
Originally Posted by AustinSchuh View Post
Not a bad start.

I keep seeing people here make the same mistake, and it bothers me enough that I'm going to say something.

Think of sheet metal like paper. Go ahead and grab a sheet and play with it. Bends add lots of strength. Wherever you break the bend, you make the part significantly weaker.

The first thing that I see when I see the side rail parts is that you broke the bend both around the transmission and on the outer edge all over the place. This significantly weakens the frame. I'm going to make a wild guess and say over 2x weaker when in compression. (Props for anyone who does FEA to get a better estimate.) Do yourself a favor and figure out how to not brake the bend. Space the wheels in away from the edge, or whatever it takes to make that happen. That will take your frame to the next level and make it bullet proof and incredibly stiff, which is exactly what you want.

If you don't believe me, print your robot out on paper at partial scale, cut it out, and assemble it. Try twisting and bending it, and see what happens.
Thank you for the feedback, Austin. I agree with you and this is the type of feedback I hope to get by posting these, I'm still learning. However, I don't think it would be able to be assembled if the belly pan had a full flange along the outer edge of the wheel wells.
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