Need troubleshooting help

[Jim Tobias]

I'm hoping that someone here can give me some help with this finishing issue. I have been wrestling with it for 2 days and cannot seem to find the culprit. The finish is Target Superclear 9000 WB Poly. The equipment is Fuji Q4 Pro with XT Gun. I sprayed it on 2 small sets of upper cabinets and it was fine. Then I built the base cabinet and started to spray the drawer faces and this is what(picture below) I am getting. I ordered fresh product after cleaning gun multiple times did not resolve issue. While waiting on finish to get here, I sanded the drawer faces back to fresh wood. I sanded with Festool sandpaper. I wiped down with 50/50 DNA/water mix after sanding. So today after receiving new finish, I stirred it up, sprayed and got the EXACT SAME ISSUE again. Dimples/fish eyes/craters....whatever you want to call them. It looks likethe finish is spreading away from a small spot.
When I say I cleaned the gun.... I took it apart and cleaned off all parts with water and then DNA.
Oh, and I called Jeff at Target and he thinks it's contamination. I explained about my process and he seemed to agree that I was following correct process. I later called Fuji and they had no suggestions as to problem other than "clean the gun real good".
I cannot figure out what the culprit is that's causing this.........as you can tell.
Any suggestions, thoughts would be greatly appreciated.

Jim

Finish Issue.jpg

[Ed Edwards]

Hello Jim,
You cleaned the gun and then re-cleaned it, sanded the faces back to bare wood, sprayed the same panels again with new product. Have you tried to spray a completely different panel, or a piece of scrap wood or even a piece of cardboard? I would try spraying the backs of the upper cabinets maybe.
To me I'm thinking contamination i.e. silicone, or something along that line. 'cause sure looks like fish eyes to me.
Please post the resolution so we may all learn. I hate it when a plan goes south.
Ed

[Wayne Lomman]

Jim, this almost certainly contamination. I use 2 methods to fix this.

The first way is simply to add anti-silicone drops to the coating. They are available at any auto paint shop in Australia but you will have to check what they are called in the US.

The other way is to dust an almost dry coat just on the spots. You do this by turning down the air and fluid on the spray gun and very delicately building up successive layers of almost dry spray. Leave it for a few minutes to dry out and then apply a light coat to the whole surface. Let that cure and then apply a final coat and the job is done. This method exploits the fact that the coating has to be wet to separate - keep it too tacky to do that and you have it beaten. Takes a bit of practice but I have been doing this for at least 30 years and it works. Cheers

[Jim Tobias]

Wayne,
I tried your idea today after cleaning the gun again and spraying lacquer thinner through it and then spraying 2 rounds of water through it to clean all the lacquer thinner out. I then tried the thin "dust" coat ideas. At first I could not see any craters so I thouht it was working......but as soon as I got to building a surface, it started cratering again.
I'm going to keep trying to test different ideas until I find the culprit. I solved the immediate issue by going out and buying 3 rattle cans of spray poly and put the finish coat on the drawer faces.
But I have to resolve the problem long range so I can use my Fuji again.

Any other thoughts and ideas are more than welcome.

Jim

[John TenEyck]

Hi Jim,

Your last post suggests that the contamination is not on the wood as the rattle can poly came out OK, right? So the problem is in your gun. Could it be coming from the turbine air? I have no clue about turbines but since you've repeatably cleaned the gun and the problem is still happening, the only thing left is the air.

Try brushing the finish on one half of a piece of scrap. If it dries w/o fisheyes, try spraying some on the other half. If you get fisheyes then it's in the gun. I'm betting the air is your source. You might be able to prove that by blowing just air with no finish onto another piece of wood. Then try brushing some finish on that piece of wood. If it fisheyes you'll know the air is culprit.

John

[Jim Tobias]

John,
I will try that tomorrow. I wondered that also but in talking to someone at Fuji, the guy there told me that the turbine blades are sealed and that the air could no be contaminated. But, it has to be coming from somewhere and the possible sources are being eliminated.
I am also going to sand and spray a different species(walnut or something) to be sure that this batch of Maple wasn't somehow contaminated when they milled it. I know that seems highly unlikely, but I'm running out of ideas.
Thanks for the idea.

Jim

[Wayne Lomman]

Jim, I agree with John. There aren't many options left. Cheers

[Prashun Patel]

Are you thinning the finish at all?

[Jim Tobias]

The first batch I had thinned maybe 5% with water.
The new can I did not thin at all.....straight from can.

Jim

[Prashun Patel]

Have you cleaned the air filter? Mine collects a lot of white powder that I am shocked doesn't cause me more problems.

[Conrad Fiore]

I'm still curious about the suggestion to spray another piece of like material to see if you get the same problem.

[Jim Tobias]

Prashun,
I did clean the filter(actually washed and dried it) after receiving the new batch of finish. It was dirty, but not out of the ordinary.

Conrad(and others),
I'm going to finish attaching drawer faces, etc. today so I can be finished with this cabinet. Then I'm going to begin going down the list of suggestions to try and find the culprit. I'm also going to call Fuji again about the air line and any other possible turbine issues that could be contributing to the problem.
I will post results as I test.
Thanks,
Jim

[Andy Giddings]

Jim, are the fisheyes always in the same area of the panel, or are they random? Can't see any comment on this in the thread but if they are always in the same area it would seem to indicate the contamination of the wood is deep and not just on the surface

[Jon Nuckles]

Jim,
Don't leave us hanging, man! This is a mystery that needs a satisfying resolution.
Jon

[Jim Tobias]

Jon,
I haven't forgotten.....just been putting the cabinet together and he just now came by and picked it up.
I am headed back down to shop and will try brushing a few coats and also spraying a few coats on different species/boards.
I will report back as soon as I find any results/or not.

Jim