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Old 03-04-2011, 04:41 PM
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John Brohm John Brohm is offline
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Quote:
Originally Posted by dbrent
...

When I went to remove the masking tape, the paint along the edges lifted and came with the tape leaving a ratty looking ragged line. My guess is since I was painting over a gloss surface that the black didn't get a good enough hold.

I have to admit, spray can painting baffles me. When I do a plastic models, I typically shoot Tamiya flat acrylics through a double action airbrush and never have any trouble even with the most complicated paint schemes. I don't even consider that my paint might attack the primer, or that removing masking material will ruin the paint edge.

Don


Hi Don;

I've never used the green masking tape, but the problem sure sounds like the solvent in the paint is too hot for the adhesive on the underside/edge of the tape. If the solvent dissolves the adhesive along the edge then no matter how much burnishing is done, the paint is still going to leak/wick under the edge.

An analogous problem could occur with the old formula Krylon paint. I typically like to use Tamiya masking tape, one of its properties being its thinness, which contributes towards some nice clean paint separation lines. But I found that if I laid the Old Krylon on too heavy, its hotter solvent would actually scald the surface of the underlying paint from above (the Tamiya tape being thin, and not being an adequate barrier in this case), leaving a rough patch when the making tape was pulled up. In this case, the problem wasn't the edge but the ability of the tape to be an effective barrier to the hotter solvent.

In your case, my money would be on trying a different masking tape with the paint you're using, and see what happens.
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