Hello from the summer of repairs! After 4 great seasons of sailing my '77 DSII out of St. Albans bay on lake Champlain, I decided to tackle some repairs, including fixing the jib tracks, barrier coating and painting the bottom (not blistered), a few gunwale dings, and reducing wobble in the CB. Oh yeah, and there were a couple little leaks from previously plugged holes near the lower gudgeon on the transom. Not having a garage or barn, this project had to wait through the coldest, snowiest April we've had in a long time. Since then, work has been very sporadic. I decided not to mess with the CB too much but did my second replacement of the downhaul (posted that story in the recent-ish thread.) I will be happy to answer questions and post more detail about my barrier coating experience, done with West 105 and 422 additive. Later.
So I started poking around and drilling out the failed plugs in the transom and then removed the gudgeon to find about 7 old holes plus the 2 currently used ones! In hopes of making a small repair in just that area, I cut out a small section of the transom skin(s) around the gudgeon, which revealed that my transom is a double plywood sandwich on 3 slices of fiberglass! See pictures. I cut out one more section since that direction had obvious rot The other direction (right side) actually is hollow about 2 inches past where I cut. So there is a lot going on in there that I don't understand. Maybe the left side has more plywood for motor support, because I've drilled pretty far to the left and am still hitting rotten plywood.
So my next (and what maybe should have been my first) step might be to cut most of the transom skin off and attack the whole thing. Yes, I know most people do this from the inside, but too late for that now, and access is much nicer on the outside. I guess I would cut following the lower profile of the bottom about an inch higher like I already started. Not sure if I would go all the way to the top corners of the transom, or how close under the transom cap I would cut. The cap seems very beefy. I do NOT plan on grinding a 12:1 bevel ratio for the skin replacement. I just want the boat to be sound and don't care if the repair is obvious.
Has anyone else seen or worked on a triple-skin transom like mine? I don't see how one layer of both ply and glass could have been added after production, but it's possible. Any ideas on how much should be removed side to side? And I'm really not sure about the cap. If I cut below the cap, I suppose replacement plywood/epoxy will be more difficult if I have dug out the last inch, like at the bottom. Maybe I should just cut the cap off first. Ouch.
The other option is to leave some of the rot and patch what I've done, but it wouldn't be easy since I have to maintain the draining ability of the bilge. I can't just pour thickened epoxy in between the inner and middle skins or it will plug the area in front of the drain. Fitting pieces of epoxy coated plywood in there won't be easy either unless I can grind out some squarer angles. Between the middle and outer skins is less of an issue since the middle skin ends flush with the front of the drain tube.
Any suggestions or information are very welcome, and commiseration helps a little too.
Thanks and enjoy the water!