A lot of cams pass thru my shop and many have beat-up threads. I made a die from a cam nut by cutting 4 grooves in the threads. I have 2 of these dies, one from a looser nut and one from a tighter (smaller i.d. nut). First I file any damaged threads at the front of the threaded area, then use the dies. It takes time and patience but gets the job done. All nuts, and all cams, are not the same. Years ago I received a cam from Canada with the gear and nut still in place. The gear had spokes, as opposed to a solid center area, and there was a thin hardened steel washer under the nut.