Paint ignorance question
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Paint ignorance question
I have single stage urethane. If I touch up a “head of a pin” size interior nick with an artists brush will the paint ever dry hard enough to sand a bit without hardener added ?
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I believe the answer is NO. But if it does, it may take a few years before you can sand it.
Acrylic enamel without hardener will dry hard, but it takes weeks. With harder it is overnight. Synthetic enamel takes months or years.
Larry
Acrylic enamel without hardener will dry hard, but it takes weeks. With harder it is overnight. Synthetic enamel takes months or years.
Larry
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Are you sure the "touch up paint" is original urethane??
I would paint a bit on a solid metal surface (from my workbench) and then watch it over the following few days/weeks. That will tell you what you can ultimately do.
Larry
EDIT: Have your sample "color scanned" by local auto paint store and get it in acrylic enamel. You can even get this put into cans for a few extra $. It will be fine for touchup of nicks and rock damage etc. A good auto paint store can/will even do a bit of color matching by eye/experience if needed to adjust color. But the current color scanners are damn close........especially for non-metallic paint.
I would paint a bit on a solid metal surface (from my workbench) and then watch it over the following few days/weeks. That will tell you what you can ultimately do.
Larry
EDIT: Have your sample "color scanned" by local auto paint store and get it in acrylic enamel. You can even get this put into cans for a few extra $. It will be fine for touchup of nicks and rock damage etc. A good auto paint store can/will even do a bit of color matching by eye/experience if needed to adjust color. But the current color scanners are damn close........especially for non-metallic paint.
Last edited by Powershift; Apr 12, 2020 at 11:42 AM.
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I'm getting out of my comfort zone on paint, but lacquer and enamel will cure faster with heat by more quickly evaporating the solvent/thinner and (for enamel) promoting the gradual hardening reaction with air and sunlight exposure. Urethane is a true chemical reaction to harden and requires two parts mixed together to get the reaction started.
Larry
Last edited by Powershift; Apr 12, 2020 at 11:48 AM.
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Frankie, shake or stir you urethane base. If you stir it, let enough of the stirred paint drip into a small jar cap or other small container. I use a wooden coffee stirrer. Then dip the tip of your artist brush into the hardener at roughly the correct ratio (4:1 is a good ratio if you don’t know) and use the brush to stir it up. Dab the spot 2 or 3 times allowing a few minutes between dabs. Once it fully hardens, have at it to blend.
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It will harden - just a bit slower and not as hard. Think of it as acrylic enamel without the hardener added. I've done a little touch up with an air brush in a door jamb of my Cobra that a screw head nicked the paint when I closed it and blended/feathered it out over about an inch diameter. After letting it set for a week or so I sanded and polished it out to where there's nothing to see - no dimple, no ring, no color change, no nothing except smooth, black, shiny paint. I would not do it for a larger panel blending repair on an outer panel but for a small chip it's OK.
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I have two cars painted with the same stuff, Frank. One in 1985 and one in 1993. Both still look good. No clearcoat to peel off. My advise is to use matching touch up paint available in auto parts stores. I have an old can of Premium Decor PDL-21 "Americana" waterborne acrylic enamel that is an EXACT match for Roman/Riverside red, and it applies easily and dries quickly. It's made by the General Paint MFG C0.out of Cary, Illinois.
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One of those, "...why am I so stupid" situations. My 63's driver's side door handle was loose (never noticed it before) so I took the door panel off ans found out the window crank "U" clip was on backwards. (Damn). 10 minutes of fiddling to get that out of its incorrect position. Fixed the door handle and the Al Knoch repro door panels (the very early ones like I have) are not formed very well at the top front and rear and in positioning the door card to go on the interior metal edge hit the rear coupe door post just above the panel....a little bit of blue tape would have prevented it. My fault. I'll let the touch up "cook" for a week and see what happens, and, try some of the above suggestions if it doesn't work out.. Nobody else would prob even notice it, but I know its there.
Last edited by Frankie the Fink; Apr 12, 2020 at 12:21 PM.
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Do what Herman59, Barry, said. Mix paint and hardener. Put a hole in blue painters tape big enough to expose the damaged area. Dab the paint on. I sprayed acrylic enamel once without the hardener, very very bad idea.
I'll gladly trade my stupid situation for yours. I've been buffing trim. I wrapped the front header molding around the buffer 3-4 times having to straighten out the damage each time until I couldn't anymore. I may be able to patch it. Then I wasn't finished with stupidity I was buffing the lower windshield molding and wrapped it around twice. It takes me at least an hour to restraighten after screwing it up. I tried a guard and positioning and couldn't keep from doing this. Then I thought maybe I'll turn the buffer around. I said nope dummy that won't fix anything. Then the light clicked on, just move the wheels to the other end. DUH.
I'll gladly trade my stupid situation for yours. I've been buffing trim. I wrapped the front header molding around the buffer 3-4 times having to straighten out the damage each time until I couldn't anymore. I may be able to patch it. Then I wasn't finished with stupidity I was buffing the lower windshield molding and wrapped it around twice. It takes me at least an hour to restraighten after screwing it up. I tried a guard and positioning and couldn't keep from doing this. Then I thought maybe I'll turn the buffer around. I said nope dummy that won't fix anything. Then the light clicked on, just move the wheels to the other end. DUH.
Last edited by Robert61; Apr 12, 2020 at 01:51 PM.
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Frankie, I won’t claim any more knowledge about today’s paint than you. Had my 64 painted last year, Riverside Red. Painter intended to leave some paint for me ( I was buying the paint ). He used it all. So he had the supplier mix a small amount of the same urethane enamel, but with an additive (unknown what to me) that makes the urethane air dry. Still liquid in the can, and perfect match. So good that I had him do Rally Red for the 65. Air dries and after sanding, buffing and polish is so good I can’t see where I touched up. I’m usually not that good at touch up.