Fiberglassing MDO

[drs3317]

Just starting a project which will include using MDO which I will epoxy and then fiberglass cover.

Should I buy the "primed" MDO and how should the MDO be preped before epoxy.
Thanks,
Danny

[PAR]

I've used MDO quite a bit, though the quality has dropped dramatically in the last several years. Do not get the primed stuff, you'll just have to sand it off. I've scuffed up the rosin coating with 60 grit and wet out over it with success, but technically the rosin face should be removed for the best bond. Of course, it should be cloth set in epoxy as poly doesn't stick well to wood and has issues when around moisture. I've pealed layers of MDO glued face to face with and without the paper coating and both had very good bonds, though the wood to wood bond is better then the rosin to rosin bond, but not enough to warrant wholesale removal on every sheet, when a good scuff with an aggressive paper seems to work well enough to lift the fibers of the wood during separation tests.