This is an incredibly common procedure in the model airplane world when doing layups on composite and foamcore wings. Primary reason is the use of lighter weaves that like to deform or pull when snagged. The 6oz stuff y'all use isn't as picky, and the process is pretty unnecessary.

As for bonding, some of the aircraft built see some really incredible loads, with lots of flexing and movement- I haven't heard of any problems arising from a _light_ coat of spray77, nor have I seen any hazing.

However- Sample it for yourself! Nothing like practice.

: Hi Charles,
: I've never done it (and will never do it).
: Firstly I think spray adhesive will somehow remain visible under the epoxy.
: Secondly It will prevent the epoxy from soaking into the wood
: Thirdly, I doubt whether it will help much to stop the wrinkles, because you
: have to lay the glass down on the adhesive and get it to drape. I reckon
: that you will be tearing your hair out and your fibreglass off after a
: while.
: JohnK