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Hello all,

I'm finishing a test piece before starting on the larger project. The test piece is just an 8x20 piece of 3/4" Oak Veneered plywood. I started out sanding to 220 grit, applied a stain; I let the stain dry for several days, then began applying multiple coats of water-based gloss polyacrylic. I'm using my new Fuji Mini-Mite 4 turbine sprayer to apply the poly and I load up the test piece with enough poly so it looks 'wet' in reflected light, i.e. perfectly smooth and reflective. After it dries for about an hour, I begin to notice very tiny closely spaced dimples over the whole surface; I think the term is 'orange peel.'

I don't know why this orange peel effect is occurring. I've sanded it away and re-applied poly but the same thing happens. I'm letting the coats dry overnight so I don't think it's due to the poly not being dry.

I'm pretty much a newbie at this finishing game so any help is much appreciated.

Thanks,

Kevin H.
 

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If you spray your object piece in a horizontal position (laying flat), and get enough material to puddle, that can be the problem. It can't be sprayed heavy enough to run if in the vertical position.

Other problems could be not enough material (the surface can get rough), or being too close, moving too slow, or, too much air pressure at the tip of the gun.

HVLP produces a less visible spray than a conventional spray gun. I try to spray pieces in a vertical position . I use a lot of light so I can see how wet my passes are. The first few coats over a stain I usually use just a thin cover coat to get some build. Thereafter, wet coats that look nice and shiny but not wet enough to run.

You might try thinning with 10% water for a better flow.






 

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I would bet your problem is your are either spraying to heavy of a coat, or the Plywood is sucking up the finish as you apply giving it an uneven texture which compounds as you build more coats. I always use a Sealer whenever I spray anything, so I get a good even coat with the clear.


I spray WB Polyacrylic on guitars from time to time, and I don't have any orange peel problems with it through my Gravity gun. With that stuff, I like spraying it till the surface starts getting shiny. Then reapply when its dry enough not to run.

That Polyacrylic sands very easily, so I would take some 320 girt paper to it and sand it even. Then throw some more coats on there.
 

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Generally, orange peel is from spraying too heavy, which is real easy to do on a small piece 8"x20". However, these closely spaced dimples might be over the pores in the grain which is somewhat common on red oak and really possible on lesser grades of red oak plywood found at discount lumber yards.
If this be the case it can be remedied with a paste wood grain filler or just leave like it is. Some people like the pores telegraphing through.
 

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Discussion Starter #7
It appears from these replies that I am spraying too heavily. In my attempt to be brief, I left of the part where I applied a wash-coat of shellac after the stain had dried and then applied a pore filler. I don't think the orange peel is from the pores.

I think the suggestion that I am applying the WB poly too heavily is right on the mark. I thought that if I put enough on so that it formed a nice wet coat I'd get a smooth finish. I'm going to sand it smooth tonight and try applying a lighter coat. I'll let you all know the results.

Thanks for all the helpful replies.

Kevin H.
 

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you need to aply a sanding sealler over the oil stain. paneling is laminated and very porus
i personally never mix oil and water product
 
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