I live in the south where we have little rust problems, but my 2001 rear leaf spring hangars rusted out bad. I bought new ones and bolted them on with grade 8 hardware. They never moved since 2007. Everyone told me I'd better weld them on or else. Or else has never happened but this is a daily driver not a hot rod or offroader.
Mechanical engineering 101:
A lot of technology goes into what is welded and what is riveted and what is bolted
Originally bolted is usually for items expected to be removed during the expected life.
A lot of the frame is riveted to allow the tiniest bit of motion, especially twisting. If you weld what was riveted, two problems: first, you can get fatigue cracks since the metal assembly can’t give, and second, the heat can and will change the steel characteristics making it more susceptible to warping and/or fatigue cracks.
The big rivets are a factory item to save money. Not practical to replace in the field, so bolts are the option.
& finally, “torque” is actually more important then “strength,” with the assumption the nut/bolt/washer strength is adequate. Bolts (or anything) are torqued to maximize the tension on the bolt, the strength, with a safety allowance for further strain on the bolt before it fails. It’s not a matter of tightening as much as possible is better, it’s a matter of proper tension, not max tension.
The quality of the repair also relies on the bolt diameter and hole diameter being correct (not necessary the same size). Not challenging anyone, but bolts that are too hard/strong might not “give” and cause a fatigue crack in the frame. It all has to be matched.
& one last thought in mechanical engineering, the bolt actually rarely carries the load. The bolt pushes the two pieces together and creates the right friction level, and the friction actually holds the strength.
Having said all that, I have no idea how to look that up for a 30-yr old shock mount, but I know it should be bolted (to replace the rivet), not welded, if you want long life.
I forgot, did you want to know how to build a clock or did you just want to know the time?
Hope it helps!!!