newbie transom help please

The areas you haven't yet exposed, by removing the interior skin will be the usual places to see the worst of rot, in the core. So, yep, this means cutting away the sole, any supports, braces, etc. and getting at the inner skin and core.

 

Hi Par. apoligies the rain here is not great for glassing. Im grinding the ridges and solid horizontals flat. Intention is to lay 3 layers of 3/4 ply down then laminate in epoxy and several layers of bi-axial.

As per picture, all ply is out the transom. except the lower middle. The rest was laminated in solid fibreglass, (in all the corners and edges).

Even though I have cut the rot out, I think I will still cut into the moulded deck floor and deck upstand to tab to the hull. I will replace knees with like for like closed cell foam and fibreglass thickness.

Does it make any difference tabbing knees to transom skin, then ply. Or ply transom, then knees tabbed to the new transom? My boat seems to have been constructed the 1st way. Im ensuring all elements of the hull drain into bilge well. as the hull was storing water before.

 

Hi Par. I have not had time to progress the transom. Yesterday I gave it a good coating of thinking about, and in the middle of the night i started sketching it. Unfortunately I couldnt be bothered to get up at 4am and recover work laptop with CAD on it from car, so its probably the worst drawing in the world, ive knocked up. Even worse was the previous effort on my daughters ipad and crayola app

My concern is, basically the ply was only a centre section of transom. The edges are solid GRP, and solid grp bridges gap between deck upstand and hull, and deck and transom, and hull and transom.

The boat has a moulded deck design, with foam snadwich, and solid corners at transom end only. There is very little hull for me to tab too, just the centre, below ply, this goes forward about 10" until tank bulkhead If I were to cut deck to gain access to hull, parallel with transom, I would only gain around 2" of transom area to tab, and would also hit the 1st foam stringer (which is dry). The strength in the undisturbed monocoque is concerning me.

Along the deck upstand, the solid corners go forward about 2", then the deck to hull upstand is hollow.

I have not disturbed the solid glass corners, and the skin perimeter finishes shy by about 1.5" before the solid edge, so can I just replace the ply, with like for like size, and take the glass to the corners, with a suitable taper??

Not shown on drawing was a horizontal half round foam cross support, which ran across 3/4 width of transom. This was encased in 1/2" laminate and tapered off to edges, to the solid grp. Additionally where the lower edge of ply ends, there was also a foam taper, which was laminated over, and created the transition to solid grp again.

Any ideas, much appreciated,