Not a machinist either so no help here, just a reminder that heat, such as that from a torch, can reduce or destroy the factory heat treating properties or temper.

Personally, I've never had good luck with JB weld and would try the permanent (red) Loctite first.

One of the places I worked at heated cylinder jugs and pressed them onto cylinder sleeves which were cooled with liquid nitrogen. As the jugs cooled they contracted and as the sleeves warmed up they expanded so the two parts became as one. Likewise for some bolts that hold aircraft engines onto the airframe. The bolts are frozen, installed and torqued, then become very tight after they warm up.