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Dan2+2
05-30-2007, 11:33 PM
The big dummy painting my dads Skybolt fuselage got 3 big runs on the turtle deck. With polytone paint how long should this big dummy wait to wet sand them out? Or is their a better way to fix them? I was on the final coat and tried to spray a little wetter to let the paint flow better. That white paint in the sun is hard to see while painting, is my excuse!

cruiser
05-31-2007, 07:27 AM
My guess is that you have 2 options. Wet sand them out or take the material off with MEK or reducer on a rag and wet sand for "smoothness" and spray again. Removing with reducer will go down to the poly brush. Depends upon how much material has been applied and how bad the runs are. All poly fiber products seem to work best when applied in mist coats. Gloss is achieved by spraying cold material in the coolest ambient temps you can which slows drying. Refer back to mist coats again. Heavy coats = runs. If you cannot see the weave of the fabric when complete, too much material was applied. :(

Jon B.
05-31-2007, 07:40 AM
When someone put runs in my Poly-Tone, I rubbed out as much as I could with a finger while it was still wet. The next day, I wet-sanded the rest of the marks out and applied the next coat.

I disagree with Cruiser's "mist coat" technique. That's fine for a first coat of urethane paint but the Poly-Tone goes on pretty wet. How wet? Wet enough, but not so much that it sags or runs.

That's the beauty of Poly-Tone finish; you can sand it and re-spray for fixing boo-boos and not have to take it down to the pink with sandpaper.

Jon B.

cubscout
05-31-2007, 09:27 AM
Boy, glad I've never had runs in Polytone :bad-words: , and wish't this website had been around when I "might" have.

The quicker you sand out, the better. "Green" polytone really loads up the sandpaper fast, but better than the alternatives. And RTFM (read the Polytone manual) for more helpful suggestions.

Best luck, eh? cubscout

Steve Pierce
05-31-2007, 11:25 AM
I would wet sand today and re-shoot. I always carry a roll of masking tape in the paint booth with me. If the paint runs I can get the run off most of the time with the tape and re-shoot.

cruiser
05-31-2007, 06:36 PM
Guess I should have added an "in my opinion". Actually the poly-fiber manual recommends a mist coat for the first color coat followed by a wet coat. "To wet" causes runs while "to misty" by a new painter is generally about right. The manual also recommends chilled material for gloss rather than more spraying. I guess the most neutral advice is to follow the manual.

Dan2+2
05-31-2007, 09:18 PM
I wet sanded today with 400 grit and a little dishwater detergent for lubrication. Came out flat as can be. I will probably final spray tomorow. I bet the chilled paint works best because I know it dried way too fast with the fuselage in the sun. The hot surface didn't give the paint time to flow out. Wish I had a spray booth. Thanks for the replys. Steve P, How does the masking tape work to take off the sags and runs? I have wiped the polytone with a clean finger for small runs or bugs, and that works ok but big 4 or 5 in runs are too big to wipe it seems to me.

Steve Pierce
05-31-2007, 09:37 PM
It is usually a tad bit tacky because I usually see it after I have finished spraying the whole thing but it takes the run off and leaves slight imperfections in the surface which if caught in time will flow out when another coat is applied. I have use this trick with several different paints with usually good results.

Dan2+2
05-31-2007, 10:19 PM
Steve, thanks. I will try that next time. I know the polytone will kinda peel off when it is still kinda soft so the tape thing makes sense. Danny