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Crazing repair


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I was spraying on a clear today and noticed that it didn't look right. I stopped and watched as it cracked and dried to a dull finish. Short of rerouting this build to a "barn find" to explain the dull coat and light paint damage, is there a way to fix this? I have used this clear coat before with no trouble. :-/

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it seems like the base coat was not compatible with the clear coat

or it was not 100% cured yet

(kinda like the base coat shrunk a bit and thats what caused the clear coat to crack)

i'd say give it a week to properly cureand then try to wetsand the clear coat off

hopefully the base coat is salvagable

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You can always dunk the body in Castrol Super Clean and strip the paint off,then start over. Had you used the clear over this particular paint before? That may be the problem.

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Tell us what paints were used, your procedure for spraying them, drying time between coats, etc. That will go a long way to understanding what happened and prescribing a potential cure.

Testors orange and white. Cured for a week (orange) and 3 days (white). Krylon clear. The cracking was almost immediate ; as soon as it hit the paint, I could see dark splotches and cracks.

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Testors orange and white. Cured for a week (orange) and 3 days (white). Krylon clear. The cracking was almost immediate ; as soon as it hit the paint, I could see dark splotches and cracks.

Testors Enamel? If so, that is the likely culprit. Also, Krylon paints, despite what most folks say, is too "hot" to use on plastic models and especially over enamel paint.

Testors enamels take a long time to fully cure. Could be weeks/months unless you use a food dehydrator to force the paint to cure. If you can still smell solvents, it is still not fully cured. I would recommend you switch to the Testors lacquers or Tamiya lacquer spray paints. They are light years ahead of the old Testors enamels that we all grew up with.

What model did you paint? I would recommend stripping the paint and starting over or trying to find a replacement body.

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Testors Enamel? If so, that is the likely culprit. Also, Krylon paints, despite what most folks say, is too "hot" to use on plastic models and especially over enamel paint.

Testors enamels take a long time to fully cure. Could be weeks/months unless you use a food dehydrator to force the paint to cure. If you can still smell solvents, it is still not fully cured. I would recommend you switch to the Testors lacquers or Tamiya lacquer spray paints. They are light years ahead of the old Testors enamels that we all grew up with.

What model did you paint? I would recommend stripping the paint and starting over or trying to find a replacement body.

It was enamel. Its all I ever use, and I've sprayed the clearcoat a day after painting without problems.

Its a 57 Chevy, easy enough to replace. Its just the time put into prepping... :)

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It was enamel. Its all I ever use, and I've sprayed the clearcoat a day after painting without problems.

Its a 57 Chevy, easy enough to replace. Its just the time put into prepping... ;)

Don't replace it, just strip it in brake fluid(let it sit over night) and repaint

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This will sound silly, it's just something I tried successfully. I tried a two tone paint job with Testors one coat. The top color krinkled up in a few spots. I needed it finished in a few days and did not have time to sand or strip and repaint. I took a flat wide (1/4"?) paint brush and dipped it in lacquer thinner then painted the affected areas. It liquified the enamel paint. I smoothed it out, blended it in. It re-dried smooth and looking fine.

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If you have an airbrush, I'd suggest buying the enamels in bottle form, and then thinning them with lacquer thinner. The lacquer thinner will accelerate the drying time exponentially.

If you're using spray, dry the body with a hair dryer. That will also help the paint dry faster.

With regard to clear-coat: the hardware store Krylon will cause trouble. At craft and art stores, you can find Krylon Crystal Clear, which is an all-acrylic clear. This is safe for use over any paint.

A lot of people also use Future floor wax and seem to like it quite a bit.

Charlie Larkin

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If you have an airbrush, I'd suggest buying the enamels in bottle form, and then thinning them with lacquer thinner. The lacquer thinner will accelerate the drying time exponentially.

If you're using spray, dry the body with a hair dryer. That will also help the paint dry faster.

With regard to clear-coat: the hardware store Krylon will cause trouble. At craft and art stores, you can find Krylon Crystal Clear, which is an all-acrylic clear. This is safe for use over any paint.

A lot of people also use Future floor wax and seem to like it quite a bit.

Charlie Larkin

It was crystal clear, now that you mention it. Perhaps I'm the exception. :) Thanks for the tips.

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yeah i agree on the krylon (crystal) clear: if you put that stuff on too fast, it will definately destroy especially if there are semi-dry enamels beneath it. unless like you say you want to use it as a "barn find", i think a time in the brake fluid (i dont think CSC will cut through the clear) will bring it back to base. then get a food dehydrator to dry your paint in...up there in vermont i bet the air is pretty moist to begin with and testors enamels are really slow drying...a dehydrator will cut that time down to a day or so.

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It was enamel. Its all I ever use, and I've sprayed the clearcoat a day after painting without problems.

Up until now, you've been lucky. As others have said, enamels can take quite a while to dry/cure/gas out. If you lay clear over enamel that hasn't finished the outgassing process, chances are you'll get the same results. When I used to shoot everything in enamel, I'd give a week for each coat to dry before moving on.

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This will sound silly, it's just something I tried successfully. I tried a two tone paint job with Testors one coat. The top color krinkled up in a few spots. I needed it finished in a few days and did not have time to sand or strip and repaint. I took a flat wide (1/4"?) paint brush and dipped it in lacquer thinner then painted the affected areas. It liquified the enamel paint. I smoothed it out, blended it in. It re-dried smooth and looking fine.

Did you have a clear coat on this? If you did, then I'm full of it, but it seems to me it wouldn't work with color/clear. To get rid of the cracks you would have to dissolve both coats. The lacquer thinner might craze the enamel more, or the two coats would mix and be muddy. Also, I thought the one coat was a lacquer, which would make a difference. Curious to know if I am wrong.

Edited by basher
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Did you have a clear coat on this? If you did, then I'm full of it, but it seems to me it wouldn't work with color/clear. To get rid of the cracks you would have to dissolve both coats. The lacquer thinner might craze the enamel more, or the two coats would mix and be muddy. Also, I thought the one coat was a lacquer, which would make a difference. Curious to know if I am wrong.

I did clear coat it - and that is what messed up the paint. I gave it some time, considered my options, and decided that this would be a great time to make a 57 that was" kept in grandpa's barn since he passed away in 1989." Sometimes you decide what the car will be, and sometimes the car has a word in edgewise. :D Time to scour the forum for weathering tips.

Also, having a surefire way to put a dull aged clear coat on a car isn't entirely a bad thing! :lol: Thanks for everyone's help.

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