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View Full Version : Is this paint too far gone for wetsanding?



Shinystang
06-14-2010, 05:57 PM
I bought a '79 black trans-am that was repainted about 20 years ago. It seems to be a base/clear. The run-off after sanding was gray / white color.

The hood, roof and trunk are severly oxidized...water drops "stain" the surface of the flats and the reflection is almost nil. (attachment 1 and 2 are after washing and drying...the water stains)

I tried a light wet-sand with 1500 and polish with Megs wool pad and Megs 105 on a Makita rotary @ 1000rpm. The pad quickly got caked with black "gum" that wouldn't clean off with a spur. The results were marginal at best.

I wetsanded the drivers door (attachment 3) with 1000 and polished. It came out good, but it had only orange peel issues.

The next day the hood had a blotchy-haze that won't come off with hand rubbing. Probably oxidation?

Did I not wetsand enough or is the paint on the hood just too far gone to save?

Thanks for the input!

Rsurfer
06-14-2010, 06:20 PM
You really need a PTG to see how much paint you have to work with and is further wet sanding safe.

Mike Phillips
06-14-2010, 07:12 PM
I bought a '79 black trans-am that was repainted about 20 years ago.


Very cool car, saw a lot of these at these at the Barrett-Jackson event below...


Pictures from Barrett-Jackson 2010 - Mothers Virtual Power Tour (http://www.autogeekonline.net/forum/off-topic/24627-pictures-barrett-jackson-2010-mothers-virtual-power-tour.html)
There were quite of few Trans Ams at this auction, the Trans Am was made famous by Burt Reynolds and Sally Field in the movie, Smokey and the Bandit (http://www.imdb.com/title/tt0076729/)

http://www.autogeekonline.net/gallery/data/849/SmokeyBanditSallyBurt1.jpg

http://www.autogeekonline.net/gallery/data/849/2010BJM088.jpg

http://www.autogeekonline.net/gallery/data/849/2010BJM089.jpg

http://www.autogeekonline.net/gallery/data/849/2010BJM090.jpg




It seems to be a base/clear. The run-off after sanding was gray / white color.


white or milky whitish for a clear coat is normal. Gray could be an indicator of a problem or perhaps black overspray?



The hood, roof and trunk are severely oxidized...water drops "stain" the surface of the flats and the reflection is almost nil. (attachment 1 and 2 are after washing and drying...the water stains)


Clear coats will oxidize but the biggest problem with clear coats is swirls, single stage paints are a lot more prone to oxidize.

Often times people confuse clearcoat failure with oxidation and they are two different things.

Did the car sit outside in the sun since it's been painted or inside?



I tried a light wet-sand with 1500 and polish with Megs wool pad and Megs 105 on a Makita rotary @ 1000rpm. The pad quickly got caked with black "gum" that wouldn't clean off with a spur. The results were marginal at best.


Another bad indicator, especially the black colored residue.

What did you pay for the car? If you got a killer deal the downside might be having to get a quality paint job. Cross your fingers it's not ugly under the paint.




I wetsanded the drivers door (attachment 3) with 1000 and polished. It came out good, but it had only orange peel issues.


Vertical panels not as exposed to the sun or the elements...




The next day the hood had a blotchy-haze that won't come off with hand rubbing. Probably oxidation?


Leftover residue that wasn't removed? Otherwise not a good indicator.




Did I not wetsand enough or is the paint on the hood just too far gone to save?

Thanks for the input!

Hard to say without being there in person to do some testing... unless you start finding some combination of products and process that restores a hard shine, it's sounding like a nightmare.

:)

Shinystang
06-14-2010, 08:51 PM
Hi Mike!!!!

Thanks for the input!!

The history I got about the car is it spent its life in California and surrounding states. Believable because it has no rust AND the flat surfaces look rough. It looks like it sat outside for a lot of its life.

I did get the car for a good price and I knew the paint was "20 years old". The odometer shows 102,000 miles. I figured with a solid body, interior and a good motor, it was worth it. I've wanted one of these since they were new. Burt Reynolds, Jim Rockford, etc.......

I was thinking of trying the Unigrit 1500 and 3000 damp sanding with a PC7424. The worst that'll happen is I burn through and have to get it re-sprayed. What's your take? Since the car was repainted, I'm hoping to have a little room to sand without a problem.....we'll see.

If I do go with the damp-sanding, do I use the 1500 sandpaper, then 1500 polishing pad, then 3000 polishing pad?

I've attached some 20 foot pics....squint when you look and the paint doesn't look that bad!!