Re: Another busted bolt
Hi
Oxy /actelene heat is too much heat unless you have a very tiny fine torch. Pure aluminum melts with a propane torch, at 1100 degrees C. but oxidized aluminum hardly melts at all, so while you are blasting the oxidized thread seats in the casting, and nothing much appears to be happening, the rest of the casting could be about to melt. And you can warp things too.
One of the principles of freeing stuck fasteners is that you heat the fastener so it expands and breaks the oxidation's grip and when the fasteners cool they don't return to the same dimensions. This doesn't work as well in aluminum as it does in steel where one of the standard techniques is to weld a nut onto the broken stud. Pick on the broken stud. If there is enough of it sticking out weld a nut on it, or if you have the patience you can file it hex and put a socket on it, the vice grips tend to chew off what you have to work with, and you don't get as many chances. If you get it to wiggle take it slow, and use that pentrating oil. Sometimes a slight turn in to start with is a safer way to break loose stuck fasteners. Cheers.
