Fisheye with a Rattle-Can Repair

Advice on cleaning and sealcoating to prevent fisheye in a repair to an existing finish. February 1, 2015

I'm an oil finish kind of guy, but I'm repairing something for a friend and putting some rattle can varnish on to match the spray finish that's already there. I got orange peeling - spots where the finish pulled back, some as big as 1/8" diameter. My surface prep was wet sanding and washing with a damp cloth. I must admit I didn't think about orange peel. I'm thinking with the sanding I would have removed waxes, but not silicones, is that about the size of it? What should I do to deal with this? I've seen fish eye flow out, but this is spray can repairs, and I don't think that would play out well. Do I sand to bare wood, or is there something to wipe with? I'm a bit out of my element here, most of my repairs are my own work and I generally know what's been done to the piece, but this one is a mystery.

Forum Responses
(Finishing Forum)
From contributor I:
It sounds more like fish eye - you will have to sand back to remove and then clean the surface with silicone and wax remover prior to spraying, but the problem could be with what the previous finish was and you may even need to spray a shellac seal coat.

From the original questioner:
Thanks for the correction, fish eye is what I meant. Yes, this piece was probably polished a lot. I can't use a fish eye flow-out, I'm not set up for spray and using rattle cans. I was going to use either an acrylic or polyurethane spray varnish. Alternately, I can brush, though this is a piece best sprayed. Ah, how easy it would have been! But here I am. How can I put a decent finish on it? Is there a wash or an overcoat? Will shellac work? I'm all ears.

From the original questioner:
I meant to add, what specific product do you recommend as a wash? Do I sand the whole thing to bare wood first?

From contributor I:
Wash coat of shellac the 2k poly over the top sprayed on. To be honest the rattle cans will not give you a great finish - but if you plan to rub out the finish at the end and buff then this will not be a problem but may add more sanding time.

From contributor B:
There are a couple of ways to approach this. One, you could use a couple of light coats to avoid the fish eye then a couple of wetter coats. Or you could spray a coat or two of dewaxed shellac as a barrier coat topped off with the varnish. Personally I'd use a rattle can of bar top lacquer. It's much faster drying than the varnish and with enough build up it's pretty durable.

Also don't wet sand it you may be just rubbing the contaminate into the finish. Wet sanding may also be giving you the adhesion problems depending on what grit you're using. I wouldn't go any finer than 220 or a good rub down with synthetic steel wool (purple) and a (not knowing what is originally on there) quick rub down with lac thinner or acetone. The acetone won't bite as much so that may be the safer bet.

From the original questioner:
Thanks Contributor I. That was the ticket!