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Polyfiber Hole Patch Questions

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Feb 1, 2007
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I am just about to finish up my Acro Sport II restoration project. There was a hole in the back, bottom of the tail where the crankcase breather tube used to exit. It was only about 2.5" in diameter. I bought a Polyfiber practice kit to get all of the materials to patch the hole with.I followed the limited directions that came with the kit, and some hole patching directions that I found in the EAA Sport Aviation archives. I have thepatch cut, glued on, shrunk, and I have 3 coats of Poly Brush on. I still need to apply the Poly Spray and the Omni CV urethane top coat, and that is where the questions come in.

Question 1. Do I need to sand or scuff up the Poly Brush before I apply the Poly Spray?

Question 2. Will the Poly Spray act as a primer for the Omni CV urethane top coat that I am going to use? (By the way, I know that Omni CV is no longer available, but the airplane came with a couple quarts of it.)

Question 3. If the Poly Spray won't act as a primer for the Omni CV, what should I use, something from Polyfiber, or an automotive primer of some sort?

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