I would like to know if I should seal my U.S. polyurethane blank that I just shaped with a mixture of microbaloons and epoxy before I glass it? I'm a strong believer in epoxy but this is my first time I have glassed a polyurethane blank with it. There are some posts on the subject but they are a bit dated so can anybody update me on this subject?
No there is no need to do that!
It is a requirement of the blank not of the resin.
What Hans said. No sealing is necessary with PU.
Not necessary.
Not necessary. Just a good, clean sanding and screen will make her ready for glass lay-up. Let us know how it goes. Always interested in the results of an Epoxy lay-up on a Poly Blank. Which blank did you use?
Did a 6’2 US Blanks blue PU a few weeks ago with RRKK. Single 4oz bottom used 11oz of resin. Double 4oz deck used about 15oz. Tight, flat, no drainage issues… no pinholes.
I would. I do. I just finished a 6’2" a week ago that I shaped from a US Blank, sealed w/ epoxy/cabo/qcell and it turned out great. It will turn out lighter than if you don’t seal it. I don’t think sealing is a requirement, but I do think they turn out better.