[tripower]

Anyone have experience with having a set of Rally II's or I's restored where the cores were acid dipped? Two of the five Rally II's I have have substantial rust on them. I was thinking acid dipping would leave a nice smooth surface for primer, but don't know if acid is as effective as sandblasting in removing rust. Thanks

[Loffen]

Acid will remove the rust, no problem, but sandblasting will remove and change the the metal surface.

So you might think that you should go for the acid, but I just had a discussion with my painter regarding acid and he said hi was sceptical to it since he had seen a lot of cases where the paint did fall of after some years since they had not been able to stop the acid process.

Here are some pictures from my last project, the wheel has been sandblasted and the fenderskirt has been acid dipped

[paint guy]

If you have the rust chemically removed, it is usually a 5 to 7 step process, not just an acid dip. one of the last steps will be a neutralization of the acid, then a phosphate conversion coating with rinses in between. If it is done correctly, you will have no prblems with paint adhesion, as a matter of fact, it will be greatly improved as compared to un-treated steel, as will the corrosion resistance. If you blast, have the blaster use new media (black diamond, which is coal slag, will work well as will sand), don't touch the blasted wheels with bare hands (use CLEAN gloves) prime ASAP (Within an hour or so if possible) with 2K EPOXY primer, at least 2 coats to provide 2-3 mils dry film thickness (Sufficient to cover the blast profile). You could do BOTH processes (Many mfrs do), blast first, then pre-treat, but it is probably overkill in this case. If I had to choose between the two, I would choose blasting, not because its a better process, but because the potential for things to go wrong is way less. (Not many shops with a 7 stage system in operation these days, contaminated tanks, improperly titrated, etc...See above post.)

[1971WARBIRD]

the one problem i had with sandblasting was ssome of the grains of sand got in the small gap between the inner rim and the outter rim.pain in the butt to pick out, besides that it worked great. the place that did mine, bakes them then puts them in a shotbead/tumbler which takes off everything.

[mrrat1]

If you have heavy scaly rust, after blasting there will be pits to be filled.....DK

[78 GHOST]

I acid dipped my frame.. never again.

Very expensive compared to blasting and the acid kept leaching out of hard to neutralize cracks and crevices.

I'm going to use sand blasting or soda blasting from here on out.

-Matt

[tripower]

Thanks, decided to get them sand & soda blasted. Seems acid can be a PITA

[raidex1]

I had mine sandblasted but it left a rough surface and I had to hand sand them (a lot) to get them smooth enough for paint.
Next time I would use a different medium instead of sand. Glass is good I hear and there are many others.