Broken Welded nut in Frame repair?
Like many others before me, I broke off a captured nut from inside the frame. I was removing my skid pates and the bolt just kept spinning and spinning.
I was able to remove the bolt by drilling out the head until it fell off of the shaft, but now there is nothing there to attach the skid plate.
I've read that some people have used Crimp nuts or Rivnuts, but I a little hesitant to spend the $100 on the tool used to install them, just for this one nut. Is there a cheaper way to compress them then the special tool?
I could weld in a new nut, but I've never had to weld anything under my car before, so it is not the first thing I want to jump into. I'd like to see a repair that someone else has done before attempting the welding solution. So please send a link if you have welded in a new M8 nut into a hole. It seem like it would be hard to keep the nut square to the frame while you weld it in place. I also worry about the weld getting into the threads and then having to cut the whole mess back out again.
My other idea was drill a hole into a 1/4" thick bar about 1" wide, maybe 3" long and weld a M8 nut over the hole. I could then stick the bar into the frame through an access hole. Once I got the bolt started, the bar would just spin around in the frame until it his the side, providing a positive stop and the ability to tighten the bolt. I just wonder if this could cause problems long term, such as rusting or rattling.
I would appreciate any input, or links on a proper repair.