I roll wood shafts initially to get them straight and have a roller to target broadheads, to get them straight. I have never been able to get an aluminum arrow, once bent, to roll flat. I got a a bunch of old target fiberglass arrows and shafts that were discarded from a college archery program, I was surprised how crooked many of them were, they made good tomato stakes. I had some chundoo shafts, that had kinks in them, I got them all passable, but they took more work than I was prepared for and a few of them still were not all that good.