How Do You Get A Smooth Finish With Polyu
 

What technique do you guys use to apply a light, smooth finish with Polyu (Polycrylic) on Koveral. I've tried foam brushes and high quality bristle brushes but can't seem to get a good finish. How wet do you get your brush, light pressure, heavy pressure, what angle do you how the brush, one stroke, multiple strokes, back brush????? Describe the technique that works best.

Chuck

The 1st thing is to make sure the surface you are going to poly is GLASS SMOOTH - (if it isn't glass smooth you will not get a smooth finish). Then I normally spray the poly on. Your spray setup will determine the pressure and amount of thinning you will need to use. (A tip - when you can spray a VERTICAL piece of glass without any sags, runs or orange peal, you are ready to spray the plane.)

FWIW - Oil base poly WILL start to yellow in about 6 months (or less). Water base poly WILL NOT yellow. A poly finish is fuel RESISTANT, NOT FUEL PROOF.

Campy,

Are you trying to fill the weave by spraying the poly or are you just spraying a coat over the paint? I'm trying to fill the weave before applying paint.

Chuck

Chuck, I found for me to get a smooth finish,I fill the weave with rattle can sandable primer. This may take several coats with sanding off most in between coats. When i'm finished, its smooth as glass & ready for paint. You can vary this if you want some areas to look like fabric with some visable weave.....Gene

Like Campy says... the base surface has to be smooth first. If it's not smooth anything on that surface seems to be magnified buy the following layers. I find 320 grit to be "smooth enough" to lay glass and WBPU over.

Ken