Painting over varnish/urethane

[edee em]

Want to paint my railing balusters. They are stained oak coated with what seems to be varnish or urethane. Can these be painted? Do they need to be primed? Which primer is best?

Thanks

[Hopkins]

I'd use 150-220 sandpaper to cut the gloss -- sand with the grain. And use an oil-based primer. You can use either oil or latex finish coat over the oil primer.

[scott_z500]

If you don't do some serious sanding then expect the paint to peel.

[Pop]

Well, maybe:

If the surfaces are dirty or covered with tree sap, bird droppings, hand oils, etc., it's often better to first wash them with a good product such as TSP, etc.. That stuff HAS to come off and sanding's the hardest way to do it. Can't find it now, but I have a can of stuff out in the garage that'll cut just about anything off the surface, plus claims to remove the need for sanding on varnish & urethanes. I've used it with great success so far (about 3 years). It removes the gloss in a hurry, plus gets down into the little cracks and splits that are impossible to "sand" into. Then you rinse it with a hose, give it a day, and paint away. Any bare spots of course need to be reprimed but well-adhered paint should be OK to paint over. I often prime even the well adhered paint so things like happened on my back porch floor don't happen: Top layer of paint coming off, exposing a slightly different shade underneath it. I shoulda cleaned/primed it better near the doorway where it's happening. Check around your local shops; it's nothing very special.

Pop

[Hopkins]

yeah, That slipped my mind. I haven't had the need for it, but there is a deglosser on the market.

[Eddie Marano]

I was at the home depot and noticed a primer, Zinn(?) 1-2-3 that claimed they are for "painted or varnished" surfaces. Any luck with them? I see the benefit of the deglosser but that adds a step not needed if the primer works.

[Hopkins]

I haven't tried ZIN for this purpose. And without knowing for sure it worked, I wouldn't skip the sanding/deglossing step. Many products make many claims that don't really work out.