Posted by JimM on September 05, 2002 at 06:23:41:
In Reply to: Advice on mounting seats posted by Andrew Murchie on September 04, 2002 at 18:50:19:
I'd use a 3/8 or 1/2 plywood doubler, a couple of inches bigger than the footprint of the pedestal. Make it wider if you think the sole isn't strong enough. Bond it with thickened epoxy applied with a notched trowel, and glass over a couple of inches past the doubler.
BTW, most people don't use marine grade ply for the sole - a good exterior is just as rot-resistant and strong enough. Your's is probably pretty strong, although I've seen some "marine" plywood at lumber yards which made me wonder how the ratings are determined. 5-ply is pretty good for 3/8" ply, so you probably have a very sturdy sole, if it's well-attached. Let us know how you make out!