Hi Terry I have had Moneycoat stick to the poly u just fine. but would use something other than poly U for glassing center section of the wing. Poy U makes a strong glassing material for covering sheeting but I would not use it in a high stress area like joining wing halves. I would use CA or epoxy or some other GLUE. Poly U is not a glue thus I wouldnt trust it. Not saying it wouldnt work just hat I have never used it that way and would be leery to try it for something like that since there is a lot of stress on it.

Joe