Author Topic: Acid Rain Spots  (Read 3632 times)

sixt9x33rs

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Acid Rain Spots
« on: December 10, 2013, 12:48:00 PM »
I have been polishing and buffing my original paint 69 Silver Z and have had some success. Especially on the sides of the car. The top side of the car has legacy acid rain spots from the early 70's when it sat outside in Louisiana. Does anyone have any ideas on how to remove these spots? Or what is needed to "cut" the top of the paint to get down to a surface that will shine?

Thanks

Lawrence
'69 RS Z/28 Olympic Gold, 711
Flat hood no spoiler, black top, endura, 4:10
POP 39,000
69 X77 Z/28 69 711 Original Paint Unrestored
'69 X66 Convertible Cortez Silver 712 black top Endura, auto, bumper guards, am/fm rear speaker 44k miles

69Z28-RS

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Re: Acid Rain Spots
« Reply #1 on: December 10, 2013, 02:53:50 PM »
The silver of that time frame was very susceptible to uv, rain, etc.. and of course, the original lacquer is very thin.   Be aware that to get past the oxydized level of paint, you will be *very thin*, and are likely to see 'thru' it to the primer underneath....    (but when I see primer peering thru very thin original lacquer, I see 'character'...  :)

Maybe someone here will have a more modern suggestion, but you're probably not going to 'make it perfect'..
If you want to 'cut faster', you might try some 'rubbing' compound on the top surfaces, and I'd suggest using it by hand, so you can more easily stop before going too far...   I'd rather leave a little silver even with spots  than have no silver left at all...?   Follow the rubbing compound with polish and I'd also put a good coat of wax over it once you find the right spot to stop..
Gary W / 09C 69Z28-RS, 72 B 720 cowl console rosewood tint
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lakeholme

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Re: Acid Rain Spots
« Reply #2 on: December 10, 2013, 04:13:41 PM »
X2 to Gary's comments. Chevy silver back in the day was often the first to show primer streaks.  If a good compounding doesn't work, a light wet sanding would be the next step, but that makes for "the character look" that Gary spoke of.
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Sauron327

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Re: Acid Rain Spots
« Reply #3 on: December 11, 2013, 12:53:03 AM »
If the spots are not removed easily with non aggressive compounding, leave it alone and live with the spots. Wetsanding will distrupt the uncleared metallic and cause blotchiness; and overly aggressive compounding will do the same. This is not BC/CC. If you have limited experience behind a buffer let some who has experience do the job. Aged lacquer that is nearing the end of it's life from abuse and exposure will not come back. I'll walk right by restored cars to look at an original paint or driven cars with a patina. Restored cars are a dime a dozen.

rsr

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Re: Acid Rain Spots
« Reply #4 on: December 11, 2013, 01:22:01 AM »
 I agree with Sauron327 and suggest not using any sand paper wet or dry. A clay bar will clean the surface very well but you'll need a good hand polishing after that. Remember paint back then wasn't trash or imperfection free so beware before you see the primer..Good luck!

sixt9x33rs

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Re: Acid Rain Spots
« Reply #5 on: December 11, 2013, 02:37:05 AM »
Thanks for the replies guys.

This is what I have done so far.

1. Clay barred the entire car
2. Polish compounded the entire car
3. Polished the entire car
4. Waxed the entire car

The sides of the car look really good. The hood and deck lid look second best and the roof needs the most work with the most paint fade and acid rain spots.

I may try a little rubbing compound on the roof and then try the polish compound then the polish and finally wax. I don't want to rub through the paint. i like the look of patina and like ya'll said there are just not many original paint cars left so certainly don't want to screw something up.

Thanks for the help

Lawrence
'69 RS Z/28 Olympic Gold, 711
Flat hood no spoiler, black top, endura, 4:10
POP 39,000
69 X77 Z/28 69 711 Original Paint Unrestored
'69 X66 Convertible Cortez Silver 712 black top Endura, auto, bumper guards, am/fm rear speaker 44k miles

bergy

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Re: Acid Rain Spots
« Reply #6 on: December 11, 2013, 11:57:18 AM »
If metal oxides are involved - acid wash might help.  Try HCl or even HF on a very small area first.  Be very careful not to breath the fumes and, of course, protect skin.  Don't get acid on any metal parts.  We wet sanded right through the paint when trying to remove metal oxide spots (problem is that metal oxides are harder then the old paint).  Tried acid & it dissolved them.  Might not work on your problem, but worth a try - be careful though!

PURESS

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Re: Acid Rain Spots
« Reply #7 on: December 11, 2013, 12:02:53 PM »
Just thinking outside the box...never have worked on this kind of problem.....but would a baking soda paste work?   Just like on a battery post