Blistering of Finish

I painted my Apis 13 kit with Prestec. I think this is referred to as
a "gel-coat" but is really just a thickened polyester high gloss top
coat. The stuff sprays easily and wet sands easily too, and it is not
that expensive.

But..............it seems really prone to the blistering that everyone
is talking about. These are not particularly large, somtimes they
appear as a sheen if you look at the wings at the right angle, in
other places they are maybe a mm in dia and .003 tall, true bumps. The
first time I noticed them was after the first winter it was painted;
we pulled the sailplane out of the trailer, and the L.E. of the wings
were covered with them, luckily the smaller version of the bumps. I
unfortunately have no place other than the trailer and the outside
ramp to store the glider, and there is no electrical source for a
small heater or de-huminidifier in the winter.

The "good" news is these bumps mostly dissapear by mid-spring. Luckily
only a small portion of the airframe has them, and they seem to be
random as to where they show up. Guess at some point I'll have to
bring everything home and spend a winter sanding and re-painting.

Happy Holidays everyone.

Brad
199AK