Hi all. Just wondering about the real cause of fisheye. We do refinishing on old cabinet doors/drawers. There is a lot of conjecture as to the cause of, but not so much the cure for fish eye. We do add anti fish eye when refinishing and ususally helps, however, Idid a whole kitchen the other day and for the most part it came out perfect… one door ended up with fish eye which just causes greif and takes more time, eventually it never did come out perfect (just a couple spots)
All I did was resand and re-laquer. Any ideas cause/cure.
Van
Replies
Caused by silicone contamination. Put on coat of shellac to seal before the final finish.
What is the diff tween shellac and lacquer? Also, do you mean to put on before the lacquer or before the staining?
Thanks
Van
BE very careful If you get tempted by fisheye eliminator .It just adds silicone and makes the job one big fish eye .But once in your guns and shop it is a real source of trouble.It is a product used in the automotive field.
It is a product used in the automotive field.
AND in Pledge or other furniture polishes.
Gretchen
Van - fisheyes (small round holes in the finish) are caused by contamination in the wood that interferes with the finish. A common source is furniture polishes that contain silicone.
There are a couple ways to eliminate the fisheyes; you can wash the wood and seal it with shellac or you can add fisheye eliminator to your finish. Jeff Jewitt has an article at this link - Sealers and Sanding Sealers that discusses sealing fisheyes in the paragragh on barrier coats.
The alternative is to use a product like Smoothie or a similar Fisheye Eliminator. On kitchen cabinets it's a good idea to use vinyl sealer before the lacquer; if you use fisheye eliminator, add it to the sealer.
Paul
It's caused by anything that causes uneven surface tension on the surface of the finish.
Silicon contamination is one. Oily/greasy surfaces are another. Microscopic dust particles on the wood and in the air are another. Basically any contaminant that is incompatible with the finish your applying.
Various things you can do to help prevent it:
Don't use silicon carbide sand paper (I use garnet paper or scrapers).
Apply finish in a 'clean room'.
Wash and scrub the surface with a thinner that is compatible with the finish.
Use a strong solvent to take off old finishes, waxes, etc.
Blow the surface off with an air hose and/or pad it down with a tacky cloth.
Apply an undercoat to cover the contaminants (compatible sanding sealer, shellac, etc)
Wipe on the first couple of coats.
Thin the initial coats of finish (reduces surface tension).
And, prepare a piece of similar scrap wood in the same manner as the finished piece and finish it first to see if any problems develop. A simple step that can prevent hours of grief.
PlaneWood by Mike_in_Katy (maker of fine sawdust!)
PlaneWood
Planewood,
"Silicon" contamination is not a cause of "fisheye" in a finish. Contamination with "silicones," found in waxes, lubricants, and other formulations IS a cause.
Silicon is a metalic element. Silicone is a semi-inorganic polymer containing the element silicon.
Is your advice against using silicon carbide abrasives based on fear of contamination with Silicon? There is no need to avoid silicon carbide abrasives to protect against fisheye.
VL
That is correct..as far as the differences between the two "S" words..however it is the third "S" that Plane Wood may be confused on.."STERATED" silicon Carbide..The sterates are a soap like additive to reduce clogging..tho' not always a problem, that white silicon carbide paper is the culprit in some waterbased finishes. I still use it as well as the "gold"..aand IF there is a problem (rarely in my "new" work) the Zinnser Seal-Cote is the answer.
Very interesting... Very, very interesting. I recently had a fish-eye problem and, for the life of me couldn't imagine the cause. New work, and the second or third coat of poly had a number of fish eyes. I did use non-clogging paper when I sanded for that coat (but not a water-based poly). This last one came out fine, but I used Scotch-brite to scuff the previous coat this time.
Thank you for the interesting heads up.
Oh, ok. I use garnet paper anyway.
PlaneWood by Mike_in_Katy (maker of fine sawdust!)PlaneWood
thanks all for your very indepth analysis of fish eye.
When I had fisheye the other day on one door I used a little bit of varsol on the spots.
My boss said not to though he wasn't sure why. It had neither a negative or positive impact. but you gotta try.
But I will try wiping it down with the same thinner we add to the laquer next time.
The trouble is that refinish is an already big job, and rarely do we get all that many in a batch with fisheye, (and you can't tell untill you've sprayed) so going through the trouble of wiping all of the pieces with thinner beforehand is too much time to make a buck.
But I certainly will try wiping down the problem spots.
All we usually do now is apply a tiny tiny bit of water based laquer on the trouble spots, let dry , scuff lightly and shoot again. The water base tends not to be rejected and can fill the little void.
The result is usually mediocre but adequate; usually enough in an old kitchen where they are just very happy to be rid of the "old" look.
Van
Try looking at automotive precleaners .I used to use a silicone removing cleaner on autobody prep.Use it before scuff sanding as sanding drives the silicone further in to the surface
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