bumper stripping

[como]

the bumper paint on this car has to go, right down to bare plastic.

brake fluid didnt do it, plastic safe paint stripper cant get through the paint and still seems to damage the plastic on the backside, so i dont want to use it...


sanding with 80 grit on an orbital would take the rest of my life (3+ hours in im half done one of the two)

what can I do?

[328FTW]

In the end my solution was to use the big sander and 60grit. The 60 left deep sanding marks but a you lay the primer on thick to fill them.

The other solution (haven't tried on a 2 bumper yet) is a media blasting compound since the plastic deforms sometimes you can blast with certain compunds (or even a traditional sand blast) and the paint chips and comes off but minimal bumper material it taken off since it deforms instead. It really depends on the material though that works for some "flexable" materials but destroys others plus I don't know if you have a small sandblaster or not, I brought one for wheels I've never used I should have tried it myself then I could tell you if it works.

[como]

We've got a blaster but not an air compressor capable of powering it.

I'll see if I can track down some 60 grit that fits my "big" sander, but i'll be out there all night

[jasenklems]

if you go the blasting route you can use baking soda or walnuts that shouldnt hurt the plastic too much

[donnyavery]

your best will be just to bite the bullet and sand but use 180 grit if you any less even if you can fill marks with a good fill primer and sealer you'll get sand scratch swelling so that means you'll sent time and money to sand and filler primer the sealer then paint and in a month you'll do it again because all these little sanding marks will start to show up every where so just sand it with 180 clean and prep with a good adhesion promoter the prime block sand (yes this means by hand) it out then seal it and paint you have to do all the steps so why not do it right once instead of half a$$ed twice

[Carlz0r]

Originally Posted by donnyavery

your best will be just to bite the bullet and sand but use 180 grit if you any less even if you can fill marks with a good fill primer and sealer you'll get sand scratch swelling so that means you'll sent time and money to sand and filler primer the sealer then paint and in a month you'll do it again because all these little sanding marks will start to show up every where so just sand it with 180 clean and prep with a good adhesion promoter the prime block sand (yes this means by hand) it out then seal it and paint you have to do all the steps so why not do it right once instead of half a$ twice

QFT. Anything lower than 180 grit has to be either sanded down to 180 grit or filled with an actual plastic filler. Also, be careful sanding with any power tools, make sure to move around a lot. If you get the plastic too warm it'll tend to cause high spots which creates even more work.

Just out of curiosity, why do you have to remove all the paint?

[Maruki-kun]

Originally Posted by Carlz0r

Just out of curiosity, why do you have to remove all the paint?

cause he's going for that whole "bare essentials" look.

[v3gascane]

I cant find out how to get the stupid front bumper off... I know there are more screws behind the pop up headlights, but I can't get those stupid things off either. I know I'm just missing a few screws... but how the hell do I get to them?

[como]

you have to pull the bumper itself off before you can get the plastic out.

The bumper itself isnt held on by a whole lot- two big-ass bolts going straight down, and two going up into it at about a 40* angle.
once those are out, I belive the whole thing just slides/falls forward and off of the car.
protip: It's heavy.

I don't *think* there were any holding the sides to the fenders, but it's been a few weeks since I put mine back in.

[ice_mr2turbo]

240 grit is the sandpaper you use on plastic, i work fixing bumpers and crashed cars everyday, 80grit is way rough and heats up the plastic to much, you can go with 180 on it at first, but go with 240 over it