Barrier Coats for Preventing Fish-Eye
Advice on cleaning methods and barrier coat application when fish-eye rears its ugly head. November 14, 2014
From the original questioner:
I had to strip some drawer fronts and I washed them down with TSP and also some mineral spirits. I washed down again with TSP, let dry and sprayed lacquer. I encountered bad fish eye and I repeated this and still had fish eye. What can I do next?
Forum Responses
(Finishing Forum)
From Contributor B:
Strip all the lacquer off again, clean with lacquer thinner to remove any remaining lacquer and then wipe the parts down with Toluene. Use a clean rag that you fold every time you wipe so you don't use the same part of the rag twice.
From Contributor R:
If those drawer fronts are made out of a wood like oak or mahogany or a wood with a pronounced pore; you might try scrubbing out the pores with a brass bristle brush dipped in lacquer thinner or acetone. Silicone can be a devil of a problem so best of luck removing it.
From Contributor O:
You can also try adding a fish eye remover such as Smoothie to your lacquer, and re-spraying.
From contributor A:
If fisheyes are a problem, the easiest way to solve the problem is to spray very light wet coats. Let each "tack coat" dry for a few minutes and repeat once or twice. Watch what you're doing in case the fisheyes start to form but spray with a light touch and you should be alright. If you think you have silicone on the surface the worst thing you can do is flood the surface with lacquer. Spraying with a heavy hand actually causes fisheye.
From contributor G:
Coat with a vinyl sealer first.
From the original questioner:
I picked up a can of spray shellac. I was going to spray a couple light coats on them and then re-spray my lacquer. Do you think this will work?
From contributor G:
It'll work if you are spraying nitrocellulose lacquer. If you are spraying pre or post cat you'll end up with issues a few months down the line. Make sure it's dewaxed shellac if you go that route.
From Contributor Y:
We've had a couple of similar incidents recently. Contributor A's method worked well for us. Pre-cleaning with Wil-bond or DX-330 helped. If you sealer sand the coats you misted on lightly, be careful not to sand back through to the fish eyes you just covered.
From the original questioner:
To contributor G: I am spraying pre-cat lacquer and the shellac is in a Bull’s Eye aerosol can, and I didn't notice if it contained wax.
From Contributor R:
Having tried all the different routes suggested, here is my take in the order I would try them:
1. Add fisheye treatment. If you want to be really cautious by a gravity fed gun and use just that gun when using fish eye treatment - the stuff works.
2. Aerosol can of dewaxed shellac (Bull’s Eye). It is dewaxed if it's in the aerosol can, but the non-aerosol Bull’s Eye is not dewaxed. Use a light (super light) coat. Think as light as you can get it and then cut that in half. If you do that it will hold up under pre-cat.
3. Stripping it works most of the time but sometimes you still end up doing one or two.
From Contributor J:
A light barrier coat of shellac will need to be followed by super light coat of sanding sealer - two or three in the piss-coat style mentioned by Contributor A. Think dry-spray and just fog it on. The sealer solvents will burn through shellac like it isn't there if you go wet. Don't sand between. After you build up some crust, then a light wet coat. Then scuff lightly. Then go.
