Rubbing Out Badly Applied Conversion Varnish
Rubbing out conversion varnish might work well under ideal conditions. But will it save a badly applied finish? October 28, 2014
Question (WOODWEB Member) :
I've been asked to fix a dining room table top by a client. He had someone re-finish it and they used CV. It was a poor job - lumpy, orange peel, depressions, etc. It's on pretty thick too. Is it possible to rub it out for a smoother finish? I said strip and re-do, but they had it for two plus months and wouldn't cover their own work at even cost so the client took it back. I've rubbed out regular varnish and nitro but never tried CV. Is it doable?
From contributor B:
You should have no problem with it. Typically with a CV we like to let it sit as long as we can after spraying - three days minimum. The longer you wait the harder and easier it usually is. Can you be sure of the product used on that top? I would tell the client very specifically that it may not work and that it may need to be cut back or taken to raw. Give prices on both. If the buffing doesn't work then you’re back to square one. At least you covered yourself.
From the original questioner
The person who did it says it's CV, and it looks and smells like it. I did give the client the warning and he's thinking it over. I really don't think I can improve it much beyond grinding off the orange peel; the depressions are too deep, bubble voids at the moulded edge, etc. It needs to be stripped and varnished, then rubbed out.
From contributor J:
One thing that could give you a problem if you have to cut it back a fair bit to lose the orange peel is you may end up with halos where you go through the last layer that was sprayed to the previous layer. You can't lose that by polishing it out with more compound (in my experience) as the halo just gets larger. That's the danger of cutting back too far prior to compounding, but it might be ok and save you a strip, just some time/material cost.
From the original questioner
Good point Contributor J. I'm beginning to think that trying to fix it is going to be near impossible. The sad thing is I told him not to send it out to do what they were trying, which was trying to darken the finish - get this - by staining over CV as a toner and then spraying again. The guy still didn't fix the depressions from the first job he did. Nobody liked it when I said not to use matte CV on a dining room table (should be varnish in my opinion) in the first place, liked it less when I said to strip it to fix it. The finish is simply trash but to be fair I had to ask the question of the pros here. Thanks!
From contributor M:
Why couldn't you simply sand it smooth and re-shoot it with something? Most clear CV's are compatible with other brands. Or just toss on a sandwich coat of clear vinyl to seal/bind and then top with a coat of your choice sheen CV. FWIW, I've found that the Dynabrade 3/32" (the tightest orbit they offer) sanders will effectively sand the clear coat without burning through to the stain. This should ("should") help reduce halos from burning through the coats, although I've had some brands of CV that would halo, no matter what you do.
From Contributor U
I just finished a bar top with CV and rubbed out with an Abralon pad for final finish. Sand what you have with 320 not to cut through toner, build a couple medium coats, and then sand them back to flatten finish. Reduce the CV at least 30 percent and put on two wet coats back to back. Let the coats dry 48 hours, wet sand with 600 and 800 and use an Abralon pad 1000 for satin (2000 for semi-gloss). My client was very pleased.