Removing underbody coating

[jeffball610]

What's the best way to remove this stuff myself? I'd love to be able to sandblast this thing, but don't have the money. I know an angle grinder could do it, but would take awhile. I don't want to mess around too much with chemicals, but won't count them out. I was messing around a little under the car and the stuff is so old (36yrs old) that I can pick some of it off with a screwdriver and even my fingers. Should I just get a sanding wheel for my grinder? Should I just knock off the loose stuff and put a new coat over it, or go all out and take it to bare metal?

[Bill Hincher]

your best off trying the chemical remover first Jeff, some aircraft paint stripper maybe,we have two places here that ' dip' complete cars and it aint a lot of money, but it cleans them down to bare metal.
using the grinder might thin the metal when you hit it, sand blast will definatly thin the metal
just clean it down as best you can with a scraper and paint it
I used some paint that is supposed to stop rust called ' pour 15' ( I think) but I was real careful about using a resperator with it

[DJpowerHaus]

A few rally guys on the specialstage.com construction board have recommended using liquid nitrogen to freeze it off. They've posted pictures of the process and it seems to work really well.

I've used dry ice on the inside of the car, but for the underside this might be pretty difficult without a rotisserie.