Wipe-on poly over USL?

[Chip Olson]

I sprayed the doors for my kitchen cabinets with multiple coats of Target USL, and I haven't been very happy with the results: they're glossier than I'd like, despite using satin USL for the last couple of coats, and the surface is less than smooth. I expect the problem has to do with either my lousy sprayer or my lousier spraying skills (though the panels for the cabinet bodies came out OK). I've been experimenting with wet-sanding with 600 (to smooth out the surface), then 1000 and 1500, which is a definite improvement, but really time-consuming, and the samdpaper clogs up really easily and makes streaks.

Tonight I experimentally wiped a coat of Minwax wipe-on polyurethane on the backs of a couple of drawer fronts, one after sanding to 600 and another after 320. It came out more or less exactly how I want them to look, though the 320 piece would need at least one more coat. Can I get away with this, or is there some reason polyurethane varnish won't work over USL?

[Chris Friesen]

Tonight I experimentally wiped a coat of Minwax wipe-on polyurethane on the backs of a couple of drawer fronts, one after sanding to 600 and another after 320. It came out more or less exactly how I want them to look, though the 320 piece would need at least one more coat. Can I get away with this, or is there some reason polyurethane varnish won't work over USL?

Sand it to give a bit of tooth, and there's no reason why it wouldn't work.

[Joe Chritz]

Was the USL completely mixed when you sprayed it? I have noticed it takes a fair bit of mixing to get all the flattening paste mixed back in after the can sits for a bit. The fact that some are OK makes this a likely scenario.

Joe

[Matt Meiser]

I seem to remember an article in a magazine to that effect. The author opened a can of satin finish and found sludge in the bottom. He carefully strained off all the clear finish, sprayed it, and got the glossiest finish he'd ever seen. When he bought the next can and stirred in the sludge, he got exactly what he expected.

Take what I say with a few grains of salt because I'm no spraying expert, but I'm getting better at it. I noticed you mentioned a less than smooth surface. Some things that could cause that would be dry spray or dust. I've been suprised at how nicely USL levels out (and also that if I put too much on and get a drip at an edge I can litterally wipe it off wet, respray and you'll never see where it was.) What you describe sounds like what I've seen when I spray too thin of a coat. Oh, and I've gotten a rough finish by having the pressure turned up too high and creating a lot of overspray that resettles on the surface.

On the poly: A few of our kitchen cabinets were looking a little worn so I took Minwax wipe on poly and wiped them down a few times. That was almost 4 years ago and the ones I did that to still look like new. I've been planning to to the rest because I noticed some of them are starting to get the same look.

[Jim Becker]

What Matt said.

But to your original question, you can put the wipe-on varnish over the USL if you need to as long as you prepare the surface for it. Remember, anything with Polyurethane resins in it doesn't like to stick to even itself without a little "tooth" on the surface.