I found some rot in my transom earlier, and attempted to repair it today. I'm not completely happy with the outcome and would appreciate some advice.
In the center of the transom there is a piece of plywood, whose main purpose is to reinforce the area where the rudder attaches. There was an area of rot in the plywood about 2" square. When the boat was built, fiberglass was laid up overlapping the perimeter of the plywood by about an inch. As far as I can tell there is no way to remove the wood without cutting away this glass.
Lacking an angle grinder, I attacked the glass with a Dremel with cutoff disk and spiral cutting bit. That didn't do much good, so I tried a sabre saw and a random orbital sander with 40 grit paper. No luck.
Finally in desperation I made a sister repair with a piece of Redneck Teak (pressure treated pine). The sister is attached to the remaining solid transom wood with wood screws, and will also be held by the machine screws that attach the gudgeons. It's plenty strong, but I feel like it's a second-rate repair in terms of quality. What are your thoughts?