Originally Posted by
gcarter
Sorry I wasn't clearer. I meant cut away the wood around the TRS cutouts, and cut one large hole in the glass per drive. Actually, I think all you would have to do is remove the glass between the larger lower hole and the upper tiller slot. Grind and taper the perimeter of the drive hole to a ratio of 12:1 on the inside of the transom. Buy some melamine paneling from your favorite big box store, cut a piece slightly larger than the drive cutout including the ground tapered area, and screw the smooth side of the paneling to the outside of the transom. Use some #6 machine screws, or a similar size for through bolting the panel on. Use lots of screws, maybe 2" apart as you don't want anything to move. The resin will not stick to the paneling, and the paneling gives a very smooth surface to your patch.
This is where burning a sample becomes important. After you determine the original layup schedule from your burnt sample, starting w/a couple of layers of mat, make some patch pieces of glass that are slightly larger than the opening. Then each succeeding piece is to be slightly larger until the inside piece is the same size as the outside perimeter of the ground area.
After all these pieces are cut, you're almost ready to start. This method works so well you can even use matched, tinted gel for your first course. At least use a couple of coats of resin, if not gel. As soon as it starts to kick, start w/the mat. what ever you do, don't stop until you're finished. This whole layup process shouldn't take more than 5 minutes from start when the gel/resin kicks.
After the patch is cured (it'll get hot too since all the courses go on at once), carefully grind the inside so that the inside of the transom is level and smooth.
After this, you can patch the wood w/the new ply,
Coosa, or whatever.
Hope this helps to clarify.