Just for the record, yes we know it is OSP, not traditional plywood, and yes we know that the dual 7/16" layers will separate over time, and yes we know that just the undercoating will not prevent this or 100% stop the moisture.
This is just to test and finish the season out to see if we should pursue a more expensive single sheet marine plywood fiberglassed version with pad and probably grab rails.
If we do make that, we figure we will have materials enough to make two, so one will most likely end up for sale on here for anyone who likes the idea and wants one too without the labor.
I am currently waiting at the boat ramp for Trayson to get here to test this sumbyatch out and here he is posting a build thread lol.
Will post pics of the results of todays testing soon... If he gets here before dark.