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Fisheyes/craters
Started getting pretty bad fisheyes when spraying wb lacquer. Usually pretty careful with silicone. Can it be caused by baby oil? I sometimes put some on the seal around the needle of my gun after cleaning.
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Quote:
Originally Posted by was2ndlast
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Started getting pretty bad fisheyes when spraying wb lacquer. Usually pretty careful with silicone. Can it be caused by baby oil? I sometimes put some on the seal around the needle of my gun after cleaning.
Thanks Steve...as always. I'm hesitant to fisheye control. ..I don't ever do refinishing and am worried about adding more silicone to my gun etc. The fisheye's are everywhere, on all panels so I think it either is:
- my gun blowing it out. Going to clean it in acetone.
- through sand and dust off prep got it on the wood. I find this one hard to believe as I use the same sandpaper that never caused any fisheye.
- the wood (ply) was contaminated or the lacquer itself is bad. I'm going to try to spray on glass or other piece of wood to test.
Hopefully will localize the source. In any case, 8 doors need to be sanded back to wood and started over.
- my gun blowing it out. Going to clean it in acetone.
- through sand and dust off prep got it on the wood. I find this one hard to believe as I use the same sandpaper that never caused any fisheye.
- the wood (ply) was contaminated or the lacquer itself is bad. I'm going to try to spray on glass or other piece of wood to test.
Hopefully will localize the source. In any case, 8 doors need to be sanded back to wood and started over.
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Senior Member
Quote:
Originally Posted by was2ndlast
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Thanks Steve...as always. I'm hesitant to fisheye control. ..I don't ever do refinishing and am worried about adding more silicone to my gun etc. The fisheye's are everywhere, on all panels so I think it either is:
- my gun blowing it out. Going to clean it in acetone.
- through sand and dust off prep got it on the wood. I find this one hard to believe as I use the same sandpaper that never caused any fisheye.
- the wood (ply) was contaminated or the lacquer itself is bad. I'm going to try to spray on glass or other piece of wood to test.
Hopefully will localize the source. In any case, 8 doors need to be sanded back to wood and started over.
- my gun blowing it out. Going to clean it in acetone.
- through sand and dust off prep got it on the wood. I find this one hard to believe as I use the same sandpaper that never caused any fisheye.
- the wood (ply) was contaminated or the lacquer itself is bad. I'm going to try to spray on glass or other piece of wood to test.
Hopefully will localize the source. In any case, 8 doors need to be sanded back to wood and started over.
When I had a refinishing shop I would have six to eight tables in my spray room at one time and have to spray one of them with the silicone additive. The overspray wouldn't contaminate the other tables and if I rinsed the sprayer out afterwards as described above none of the other tables got contaminated. Now, ever once in a while I screwed up and sanded a table that was contaminated and then sanded another table with the same pad so then that table had to be sprayed with the silicone additive. It gets on the sandpaper and you can spread it to other work. This is why I started spraying the back side of the sanding pads with red paint to note they were contaminated.
What is a mystery is where your silicone is coming from. The only time I experienced silicone contamination on new work is one shop I worked at was using silicone lubricant on and around the machinery they were using. The finisher was having fits trying to figure out where the fisheye was coming from not realizing they were doing it there. I pointed out the use of the spray lubricant so they suspended using it and the fisheye problem went away. It is possible to get fisheye from other substances than silicone. You might think of any products you may be using for lubrication on your saws. Even Johnson paste wax can cause fisheye if enough gets on the wood. I normally wax a machine and then come back with a clean cloth and wipe off the excess. It's also possible the wood was contaminated by someone where the wood was purchased.
I'm going to try another piece with a clean gun and see what happens. I do use paste wax but I always have. BTW, it's pigmented lacquer. If I prime the doors over the lacquer could that seal the contamination in and then I just spray over top?
Wait a minute, wouldnt oil in the gun cause fisheye when using a water-based finish? Personally i think thats your problem, the oil repels the water in the finish the same way that silicon repels everything.
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The problem with silicone is it sits on the surface and anything you spray over it the silicone will float to the surface and cause fisheye so primer wouldn't help. If you are not going to use a fisheye control solvent your best bet would be to put several very thin coats of wb lacquer on. By just dusting a few coats on you don't give enough thickness to fisheye. Little by little it thins out the silicone to a tolerable level.
epicfail48, yes oil can make a finish fisheye however a slight trace of oil in the gun won't spray enough to cause a problem with the finish. If though you have a problem compressor that is dispensing oil in the air this would have the potential. A person could spray air into a clean white rag and see if the compressor is spraying oil.
epicfail48, yes oil can make a finish fisheye however a slight trace of oil in the gun won't spray enough to cause a problem with the finish. If though you have a problem compressor that is dispensing oil in the air this would have the potential. A person could spray air into a clean white rag and see if the compressor is spraying oil.
OK, I will try and spray a fresh piece and see if it happens again. I'll also sand down the doors and start laying down a few thin coats.
I'm using an HVLP turbine so ambient air humidity is all the moisture coming through the hose. I spray in my currently unfinished basement that runs a dehumidifier so it should be OK.
As for sources of the contamination I have to do some testing. I will see if it's the sandpaper, the wood itself, the gun, my shop vac attachment I use to clean off dust between coats or the lacquer itself.
I have to find the source. I could just get through it for this job but I would be risking every project after this if I don't.
I'm using an HVLP turbine so ambient air humidity is all the moisture coming through the hose. I spray in my currently unfinished basement that runs a dehumidifier so it should be OK.
As for sources of the contamination I have to do some testing. I will see if it's the sandpaper, the wood itself, the gun, my shop vac attachment I use to clean off dust between coats or the lacquer itself.
I have to find the source. I could just get through it for this job but I would be risking every project after this if I don't.
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Quote:
Originally Posted by was2ndlast
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OK, I will try and spray a fresh piece and see if it happens again. I'll also sand down the doors and start laying down a few thin coats.
I'm using an HVLP turbine so ambient air humidity is all the moisture coming through the hose. I spray in my currently unfinished basement that runs a dehumidifier so it should be OK.
As for sources of the contamination I have to do some testing. I will see if it's the sandpaper, the wood itself, the gun, my shop vac attachment I use to clean off dust between coats or the lacquer itself.
I have to find the source. I could just get through it for this job but I would be risking every project after this if I don't.
I'm using an HVLP turbine so ambient air humidity is all the moisture coming through the hose. I spray in my currently unfinished basement that runs a dehumidifier so it should be OK.
As for sources of the contamination I have to do some testing. I will see if it's the sandpaper, the wood itself, the gun, my shop vac attachment I use to clean off dust between coats or the lacquer itself.
I have to find the source. I could just get through it for this job but I would be risking every project after this if I don't.
Fisheyes can occur if there is contamination on the surface of the wood. Rod builders have to clean the rod blank thoroughly with DNA before applying epoxy finish. So far, I have been very lucky.
Edit: I recall an appliance manufacturer having a problem with swaging tubing. I suggested some silicone lubricant to prevent the collapse of the tubing. I was told that silicone on metal surfaces plays heck with paint.
Edit: I recall an appliance manufacturer having a problem with swaging tubing. I suggested some silicone lubricant to prevent the collapse of the tubing. I was told that silicone on metal surfaces plays heck with paint.
A diamond is how coal reacts under pressure.
Quote:
Originally Posted by Steve Neul
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I feel for you. It can drive you nuts trying to find a mysterious problem like that. One time we were refinishing mahogany tables which took a lot of coats of finish. When we would get close to the right thickness the finish would get cloudier and cloudier. Sometimes it would get so cloudy we would have to take the finish off and start over. I even got the rep from Star Finishing Products out to my shop and the consensus was it was common blush. I tried using retarder thinners but it didn't help. Then one day one of my guys pulled too hard on an air hose and pulled it off the compressor. When that happened it blew oil all over the place. I realized then the cloudy finish was due to the compressor putting oil in the air. I replaced the compressor and the problem was solved.
I will post back with any findings.
May have figured out the source. I raised the grain by wetting down the wood with a soft rag. Tonight I notice my wife pledging with....a rag from the same stash. They get washed but I bet it doesn't get all the silicone of it. So I basically rubbed silicone all over the doors.
Senior Member
Quote:
Originally Posted by was2ndlast
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May have figured out the source. I raised the grain by wetting down the wood with a soft rag. Tonight I notice my wife pledging with....a rag from the same stash. They get washed but I bet it doesn't get all the silicone of it. So I basically rubbed silicone all over the doors.
Dusted 4 coats but still got fisheye. Looks like I have to get fisheye eliminator. Steve, how do I clean my gun after?
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Quote:
Originally Posted by was2ndlast
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Dusted 4 coats but still got fisheye. Looks like I have to get fisheye eliminator. Steve, how do I clean my gun after?
Eff home Depot. I did more testing tonight and did all steps with clean everything on a new piece of ply and it did it again. I've wasted about $70 worth of finish trying different things and it was not the rags. Cleaned my setup with acetone, tested the lacquer on glass etc and a new piece still does it. I'm so pissed right now.
Senior Member
It's starting to sound like the lacquer is defective. I could have believed the manufacturer of the plywood used silicone spray lubricant on their equipment which got on the plywood. Since you are getting fisheye on other materials it just leaves the lacquer itself. I have doubts now if the fisheye control solvent would help. You might do another test on a 2x4 or some other scrap wood to see what happens. Glass is a bit unpredictable how wb would respond to being coated.
I cleaned my gun with acetone and sprayed a different lacquer and it sprayed smooth so yeah. Weird thing though was that I even sprayed it over a piece that had fisheye on it and it still went over it smooth. Does that make sense?
Senior Member
Quote:
Originally Posted by was2ndlast
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I cleaned my gun with acetone and sprayed a different lacquer and it sprayed smooth so yeah. Weird thing though was that I even sprayed it over a piece that had fisheye on it and it still went over it smooth. Does that make sense?
Sounds like a material problem to me.
WB finishes will also "crater" if you reduce too much and spray too much on......the finish will separate and crater without having a contamination problem. But if your misting the finish on, I bet its the WB material itself and not contamination.
WB finishes will also "crater" if you reduce too much and spray too much on......the finish will separate and crater without having a contamination problem. But if your misting the finish on, I bet its the WB material itself and not contamination.
Matching colors on different substrates is easy. All it takes is patience and beer.

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