water based Polyurethane problems

jpat | Posted in Finishing on January 28, 2008 02:08am

Hello everyone,

I was recently asked to build a pair of night stands to match an existing color. It was paint with a glaze. I was given a small factory sample. I proceeded by taking a little lacquer thinner and wiping off the glaze to get to the base color. I had the base color matched up by my local paint store. So far so good, I sprayed the latex paint and let it dry a day or so. I then glazed it with a mix of minwax colors, again so far so good a perfect match. I allowed it to dry about 48 hrs. I then proceeded to spray with latex polyurethane as a topcoat. The finished just beaded up as if I had waxed the piece first. I have used this topcoat over minwax stains on hundreds of other projects with great results, but never over the latex paint stain combination. Think I can spray a barrier coat of shellac? My only concern is the alcohol base will react with the latex paint. Any ideas??

Thanks,

John

Replies

craig | Jan 28, 2008 05:49am | #1
I have not had success with Latex and WB Poly or Enamels. I'd strip it & use a WB enamel or poly as the base coat.
MichaelTheFinisher | Jan 28, 2008 06:04am | #2

John- the problem is the latex base coat. And then the mimwax over it. I do not know why .I am not a chemist,I think its that the oils in the mimwax never really dries enough,because it is just sitting on top of the surface. And the paint does not allow the oils into the pores of the wood. That being said I have never had a problem when I sealed it with thinned shaellac.Then the poly over it.

http://www.michaelfoscone.com
hammer1 | Jan 28, 2008 02:18pm | #3
Try using a glazing liquid mixed with artist colors, not Minwax stain.

Beat it to fit / Paint it to match
jpat | Jan 28, 2008 07:29pm | #4
Thanks every one for the help... Did a test with a coat of shellac and all is good again !

Thanks,

john