I purchased a new, extremely heavy vise from Sears with jaws that are designed to be removed. I fabricated a new set of oak jaws, this time a lot thicker so that they can’t possibly hurt the yet-to-be delivered longerons. Since I now have a lot of spare longeron material, I cut off a piece and made some trial bends with no damage to the longeron.

I also re-evaluated my bending technique and decided to abandon the Orndorff method and go back to Vans’ instructions. When in doubt, RTFM!