What is the best way to prep resin models to prevent the paint to peel off easily? Tried washing in detergent & cleaning in alcohol before painting, but the paint comes off very easily. I know sanding would be a good choice, but with such a small casting & various cast on detail it would be almost impossible. Thanks…jerry
Sounds like your prep should work, but I’m wondering about a primer helping you here. Resin seems to more than it’s share of issues without primer. I should know, because I try to skip it sometimes and it just doesn’t work well doing that on resin.
Here’s a link to instructions I used for painting a couple of Sheepscot Scale kits I built:
http://www.sheepscotscale.com/site/2009/08/20/painting-solid-urethane-truck-cabs
My Oshkosh tramway maintenance truck:
My Bucyrus-Erie Crane:
I’ve painted resin castings of junk vehicles so I’m no stranger to the peeling paint problem. I’ve had success by using any one of three of the following: Gray primer, red primer, Krylon Clear Flat.
Guess I should have used primer, but didn’t want to add another coat of paint to cover the details…have to try the primer. Don’t remember having this problems with the Magnison castings I did years ago.
Jerry,
Just to be clear you have two problems.
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Your prep work, DO NOT use alcohol to clean the part. What detergent did you use? Make sure you are using a very mild soap like Dawn.
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Make sure you prime the model. Don’t worry about obscuring the details, just spray on light coats.
You can use the primer paints that Jeff suggests. After you prime almost any model paint will work on resin. (enamel, acrylics, etc.)
Seems it would make life easier if the manufacturer would remove the release solution before selling it or at least give a specific soap or solvent you could use. I like to mask & the paint usually peels off no mater what I use to clean it.
If your usual methods are failing, are you using tap water? It’s possible that could be a factor, although probably not.
I would also get some TSP (tri-sodium phosphate) or, more likely these days, TSP-substitute, and give it a try. Mix per instructions on the package, scrub it in with a toothbrush, then rinse well.
Mold releases don’t generally stick to things too well, as they’re not supposed to do that. Always the possibility of something odd, though, I suppose.
I hear ya Jerry, it would make life easier if they would remove the release solution. But another reason you are cleaning parts before you paint is to get rid of any finger prints and skin oils that either you or the factory put on the parts through handling. Dirt and dust could also be present and thus marring a perfect paint job.
Let us know if using primer helps you out and post a pic of your project.
Good luck, Derek
I am using primer & I do have some TSP…I realize everything needs to be washed before painting, but resin seems to need something extra to minimize peeling…
Hey,
So far I have not got a definate idea of what the first coat of paint was, whether it was an acrylic, enamel, or lacquer primer. All of those bond differently & support other types of overcoat bonding properties.
As far as 1/24 modelling went, with resin parts, I used a dealer that had an etching primer that seemed to create a resin bond & also create a barrier coat, for any type of enamel or lacquer coat. Over the counter stuff called ‘self etching’ did not hold any overcoats in my experience…
Most of the time, I can clean with an ‘Ivory’ or ‘Dawn’ soap, then shoot a base coat of gray enamel or lacquer, & build up color coats from those. However, I do treat the surface as fragile, as that bond is not as firm as one on plastic surfaces. (as in mask it at your own risk, peeling lifting could occur)…
All resins are ‘fickle,’ some more than others.
Only experimentation will give you the strategies that will work for you, -on those particular castings…
Don’t be discouraged, but be open to experiment, it will be worth it…
Is the problem with resin models that the surface is too smooth to have enough “tooth” to hold a paint film? Would blasting with baking soda or some equivalent surface treatment provide the needed tooth?
Joe
Actually that is more of the problem than the mysterious release agent. Most of us casters do not use any release agent with the new silicone mold materials we use. In fact the can of release agent I bought several years ago has only been used once or twice and it is one of the paintable release agents as well. Not sure what vehicle kit you were having the problem with (OP) but, if the surface was glossy then a good plastic compatible primer may be needed.
Sylvan resin models suggests using a citrus based cleaner, maybe give that a try. I’ve also heard someone suggest Blechwhite.
I’m just wondering if maybe some of the silicone could transfer to the resin during hardening, & we know that not much of anything sticks to silicone.