question about removing paint from metal parts

[rob650]

My stock black luggage rack needs a repaint.  I plan on going to one of the local bodyshops with the rack and ask them to "sand-blast"(?) it to get all the paint off, then repaint it myself with some engine enamel.

I don't have any experience with this.  Should I request something specific, like a certain kind of blast media thats less harmful to the metal?  Or just hand it to the guy and say "Here, take that gun full of sand and strip all the paint off.  Thanks Chief!"

[montmil]

My stock black luggage rack needs a repaint.  I plan on going to one of the local bodyshops with the rack and ask them to "sand-blast"(?) it to get all the paint off, then repaint it myself with some engine enamel.

I don't have any experience with this.  Should I request something specific, like a certain kind of blast media thats less harmful to the metal?  Or just hand it to the guy and say "Here, take that gun full of sand and strip all the paint off.  Thanks Chief!"

If the paint is still solidly attached, there's really no need for total paint removal. Wet sanding with 400 grit Wet or Dry, used wet, and a touch of any needed primer will prep the paint for a fresh coat of color.

If you're dead set on blasting, there are several "new" medias used other than sand... walnut shells, soda, plastic media, all these will not damage the substrate as will sand. Think "sand"paper. Also, few autobody shops do blasting these days. Custom car resto places may but most work is farmed out as the process is so nasty.

Once the part is blasted down to bare metal, primer needs to go on quickly or the oxidation process will get ya!

My 1981 R65 has some patina of age on the chassis and related components. I've been slowly rehabing them with the wet sand, primer (if needed) and rattle can technique. Looks factory, long lasting. BTW, Ace Hardware house-brand Semi-Flat Black is a ringer for the original BMW chassis paint!

Save some money and time by DIY'ing. Remember, wet sanding cures lots of painting ills.

Monte

[Jon_P]

wally world sells stuff called air craft remover. it eats paints off to the bare metal in no time, the stuff is amazing and becareful using it because it will burn the skin also. i wont use engine paint unless you plan on tosing it in the oven to bake a while (my wife is used to stupid stuff like that i do but most miss arent) your local aoutbody supply can mix auto grade single stage paint in a air bomb can and it will hold up way better than anything you get from wally world or hardware store.

other thing once you have it stripped to bare metal is to have it powder coated which will last longer than any auto grade paint.

[Ed Miller]

It's likely that the people at the shop will know more than us.  I suspect simple sand blasting won't harm something like a bag frame; the only real worries are with sheet metal which can warp.  

Jon is probably right about powder coating, though it hasn't held up that well on the valve cover of my '89 Honda car.  Maybe the combination of heat and oil were bad for it?  

Interesting avatar.  

[steve hawkins]

I have just stripped my seat base with nitromors -  a paint stripper.  Does what it says on the tin.  Worked okay for me.

I am using an acrylic paint from a rattle can primer+satin black - fine for under the seat.  Not sure I would use it for the fork legs though.

I have had a similar experience with powder coating - lower frame rails are not good after mild heating from engine and oil and petrol spillages.  

It depends on how big the parts are, where they are on the bike, how much work you want to 'contract out' at cost and how much you want to do yourself.

Horses for courses...

Steve H

Ruby - R65 Cafe Racer.
Gerty - grubby R100....