Refinishing Waxed Table-Tops with Polyurethane
A furniture-maker waxed some bamboo restaurant table tops, then had performance issues. Now, how to strip the wax and prep for polyurethane? May 23, 2007
I am making 30 bamboo (plywood) tabletops for a restaurant. The problem is, I used a rub-on paste wax to finish them. This worked great when I tested staining them with wine and such at my shop, but after a week of the wait staff wiping them down with ammonia, of all things, the tables are taking slight stains. I want to refinish them with a polyurethane or something equivalent. Any way to do this without sanding all the wax off?
From contributor P:
Should be able to wipe wax with thinner to get off. Then varnish or poly over that.
From contributor T:
Polyurethane doesn't stick to much of anything, especially not wax. You'll need to get it off with a good wash of MS or naphtha with a scotch brite pad. It wouldn't hurt to apply a coat of dewaxed shellac as a barrier. Scuff sand before you apply finish and between coats to get a good mechanical bond.
From contributor M:
Contributor T is right on track with the naphtha scrub - it's less oily than mineral spirits and dries faster. Applying dewaxed shellac (Seal Coat) is not just a good idea, it is mandatory in your situation - two light coats with about an hour between, then a couple more hours to let that set up and you're ready for either regular poly or even some wb poly. I'd use Target's Super Clear Poly - the stuff's awesome! (If you go with wb topcoats, you'd be safer to let the shellac dry overnight just to be sure.)
From contributor R:
I use wb's only, but I'd be reluctant to use them where ammonia is used for cleaning.
From contributor K:
If you use SealCoat (which you should), let dry overnight, especially if you use Target's products. There have been some reports on Target's site of problems if not letting it dry thoroughly.
From contributor S:
Get some Prepsol from an auto paint store. Done deal. 35+ years in this great industry.