I am replacing a boat transom, old 18' monark aluminum boat, transom rotted. first thought was to use a 2x12, but someone told me it would check and crack and that wasnt a good idea several people have told me to use marine plywood, i was going to double 3/4", but stuater boat works, who has built probably thousands of wooden boats, told me it. A look at what is possible when removing rotten plywood board from the fiberglass transom/stern. there is no better way that doing it correctly. this is fiberglass boat improve construction. here. Find great deals on ebay for boat transom plywood. shop with confidence..
The tango 17’s boat plans call for a transom assembled from 3 1/2″ thick layers of marine plywood. each layer was rough cut as per instructions resulting in one panel that had a couple of “ears” on the upper portion.. For a transom, the part of the boat that is supporting 300+lbs (and offset at that)and 200+hp i would make sure it was strong. $100 for a sheet of plywood isn't that bad. consider that you can cut enough pieces out of it to laminate the entire thickness of the transom.. The next step in the rebuild is the removal of the old plywood core and inside fiberglass transom skin. you will need access to the entire transom plus at least 12" up the side and bottom of the boat. depending on the boat's construction, you may be able to remove the deck cap, or you may need to make a cut through the deck and sole..
