I haven't looked too far into this, but I was assuming that since the wheels will be tig welded together pretty solidly, we would be able to ignore the fact that the wheels are just layers of sheet metal, and just drill holes for the rivets. We would of course try to drill the holes through the centers of the layers and miss the gaps between the sheets, but I don't see anything wrong with drilling in the gaps between the sheets. If the wheel breaks because we drilled a couple holes in the wrong spot in the rim, we have MUCH BIGGER problems.
Thanks for your feedback.
Did I use the PEM nuts correctly? Our machinist recomended PEM nuts instead of threading metal, but since I have never used them before, I don't know if I used them correctly.
Also, I sent the design to our machinist for inspection, and he thought that I needed to strengthen the transmission case by making it more of a box. Is his concern valid?
(PEM nuts are cool parts that are pressed into a special sized hole in a piece of metal and presto, the hole now has threads.
http://www.pemnut.com/)