Originally Posted by UnCruel

An update, for anyone who is curious. The hanger (and the tent/bag) survived the trip, which turned out to be 6 days of mostly gravel. The hanger deformed a little, but did its job of keeping the bag off of the tire. One of the J hooks relaxed, or unbent a little. Also, the part that hangs over the handlebar bent more and tightened around the handlebar, so it had to be unbent a little to remove it from the bike. The conclusion is that this aluminum is too soft for the purpose. However, when I formed the hanger I had heated the aluminum to bend it more easily without cracking, and I suppose that might have annealed it to make it softer (what little I know about metallurgy is for metals other than aluminum).