I was hanging a ceiling fan in this room when I discovered that the mounting screw holes in the electrical box are stripped. My dad has suggested using JB Weld putty, letting it cure, drilling it out with a small bit and then using wood screws. I’m a first time homeowner and have neither the confidence nor the expertise to completely replace the box. Is my dad’s route the best course of action or is it a waste of time and/or dangerous to go that route? Thank you!
Looks like a plastic box? I don't think there'd be a huge problem with your dads proposed solution as long as the screws go straight up. One problem with it is it's something that'll fix the problem until the next time the box comes out. That might be never if you aren't doing anything that'd need you to open the box again.
I bet you could get a tap one size up and just cut new threads at one size larger too. Nice thing about that is you still have nice machine threads and the original material so you can remove the screws if you need to.