Ok, so it's not vintage but i reckon it's a classic. My chipped up '06 stumpjumper ht is gonna get a lovely new powdercoat soon and i dunno whether to chemically strip it first, or let the powdercoaters blast the old paint off.
will blasting (unsure of media) wreck my alu frame?

Your thoughts please

(searched like a madman and i'm still baffed.. This seemed the place to ask)

You can blast it but I'll bet that specifiying the media used is important. Seems like the powdercoater should have a handle on that issue.

if they are good, experienced blasters, they will use the correct media on your aluminum frame and will do no damage to it. If they use "one size for all" and are gorillas there's a chance they'll use too harsh an abrasive and will tear into the frames material, BUT there's usually so much "overage" in material in a Tig-welded AL frame that I doubt even with that you have much to worry over. They can strip the paint much faster and more completely than you or I can do with chemical strippers (and without chemical burns or fumes), but usually there's a charge for it.

cheers guys, i'll just have to have a more detailed chat with em tomorrow.
As for extra charges, the all-in strip 'n coat price is £45-50 which, assuming they do a good job seems very reasonable.

If you want to do it yourself, a citrus based paint stripper such as CitriStrip is cheap, easy to use and doesn't produce toxic fumes, but it will make a mess (I used it on furniture). The stuff has the consistency of fruit jam and works pretty well. You brush it on, let it sit for an hour, and the paint bubbles and peels off. If you go this route, use gloves and eye protection. Afterwards, you'll need to wipe down the frame and get the stripper out of the nooks and crannies.

Even with chemical strippers, I understand that paintshops need to scratch up metal so that the powder coat will stick. Presumably, since they aren't removing paint they can use a softer media.

Thanks, that's probably the way I'll go considering I found a much closer company who say they usually send the frame for stripping (at extra cost) before they prep (non blast) & coat it.
Considering I'm on a slight budget at the moment, I don't mind doing it myself.

If all goes well, expect some sexy pics in a couple of weeks

FWIW When I had my frame powder coated I sanded the chipped areas till the frame was smooth if there are slight dents in the aluminum where the paint is chipped the sandblasting will not take them out so the metal needs to be smooth. It really doesn't take much effort with a 150 or even 100 grit paper. The blasting will take off the paint and rough up the metal well enough for the powdercoat to adhere better.

Good call. How's your finish holding up? Any pics?

Just had it done last month and I'm waiting for a BB and some handlebars and the pedals I ordered. When I get those I can start the assembly its gonna be sweet