Fabric shrinkage affecting the paint surface I have experienced here in mid-florida summer sun. But, it occurred only where tape overlapped the fiberglass tip. On the wing I am now finishing I plan to heat such locations to the point where the pinked edge just recedes slightly.
I also wonder about the observation that light showed through at the pinked edges of a finally painted wing. Could this be a result of ironing the pinked edges down after the poly spray silver application? I iron the pinked edges before poly spray. After that I only lightly sand pinked edges if they feel slightly rough, avoiding anything more than just smoothing. No sanding after the final poly spray silver coats. The final color coat should after this fill enough to leave a visible but smooth pinked edge. Ironing pinked edges of every tape applied, even those covered by later taping I have found to be the key to a smooth finish. Butyrate on my ceconite used in my last project seemed easier as I suspect it is thicker than poly spray. And, since weight was not a consideration, I was able to lay on many coats of the silver allowing frequent sanding of rough spots. Not an option with the kitfox.