James wrote.
Do you have any experience with Concept 70 polyuerethane from PPG?
I've seen some gliders painted with it and they still look newly
finished 3-4 years later.

I used it (PPG, Concept 70) on my Genesis 2 and Williams Soaring's repair shop
has used it for years now. I like it a lot, not cheap, though. Two gallons of
Super white (Toyota 041)+ catalyst and thinner cost $600 bucks. That mixes up
to 3.75 gallons though and more than enough to refinish a 15 meter sailplane. I
sprayed on 3 medium to wet, coats and then wet sanded with 600 wet and 800 wet,
followad by buffing. Finatics will go to 1000 wet and even 1200 wet. I'm happy
at 800.

I no longer recommend Prestec (sprayable gel-coat) for ships that are left out
all the time (FBO's) after seeing a ship that was refinished with Prestec,
crack and checker after only 4 years of outside tie-down. The acrylic urethanes
like Concept 70, have held out well in the same outside environment. Williams
has an ASK-21, that was refinished with urethane, well over 10 years ago. It is
a bit worn, but still operational and she never sees inside storage.
Hope this helps,


JJ Sinclair