# polyurethane over latex paint ?



## gene (Oct 8, 2007)

I have a friend that wants to use a black water based stain and then apply Helmsman polyurethane as a top coat. The paint department at Home Depot sold her these products stating that she could do so. 
My question is whether anyone has done this in the past ?, and if so, could the same be done over latex enamel without blistering?
I know that you can use oil based paint over latex without a primer. I have always stayed away from using polyurethanes and a water based product on the same project myself. Therefore, I could not give her an answer, but thought someone here would know.
Thanks and God bless.


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## Dadoo (Jun 23, 2007)

I'd suggest taking a scrap piece of wood and trying it first, Gene. Then if it don't work, her project won't be in a mess and she can get her money back from the store.


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## Tangle (Jul 21, 2007)

I'm with Dadoo on this one. Always test an unknown finish. The poly might work if she scratches the paint with 220 grit sand paper. That's what we do with the second and third coats of poly. I use poly over shellac but never have over paint. I know she can go over it with shellac and then laquaer over that to her heart's content. Where's Douglas when you need him.


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## CharlesNeil (Oct 21, 2007)

It would do fine as long as the latex is dry and lightly scuffed, poly need's a scratch to bond, its totally mechanical in its bond,But i agree to test, and if needed a light coat of shellac as a seal coat between would work, but I feel sure as long as its dry and scuffed , say a 320 grit , it will bond fine


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## gene (Oct 8, 2007)

Thanks gang, for the response. Copied your responses and gave them to her. I advised her to go to a (REAL) paint store if she needed recommendations for any and all special projects.


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