what is the best way to strip the paint from a metal bumper?

 

what do you plan to do? If your going to repaint it or something, unless the paint is peeling off or has some other kind of issue, you should be able to just scuff the paint to get rid of the shine, clean it, and repaint.

 

I removed the undercoating from my entire metal frame with a wire cup brush chucked into an air grinder. It took a good 15 hours to get it stripped.

I'd recommend just scuffing the surface if a liquid stripper won't do.

 

That undercoating was a b1tch! It kept clogging up my wire wheel. I'd have to hit my skid plate oxidation a lil bit to get all the gunk off of it, lol.

 

i got into a little fender bender and wanted to spray it with bed liner.

 

Definantly take a wire wheel brush to that one, and get it down to bare metal. Then treat it with a cleaner, primer, and paint.