Do yourself a favor....put a plywood transom in it

I will, I'm just between marine and exterior.

I wonder if fiberglass resin would stick to starboard?? Would be heavier but basically rot proof. Would have to laminate a bunch of 1/4" for strength though.

+ 1 on the ply transom

Marine grade ply is "Free of voids" within the laminate plys where exterior can have air pockets from knots that fell out of the ply or whatever defect that left a void.

Its a coin toss if the mfg'rs use the same adheisive to make exterior or marine grade ply. Seal up the new laminates really well and it's a one time job.

Cool project... and you are going about it 100% - get rid of the cancer now and enjoy the boat when she's completed!

Penske board was used in my Chris . Builder said it's stronger , lighter and lasts forever .
I've been where you are . Great thread , keep it up .

You deserve a lot of credit taking on this project. With all of the grinding you're doing in this humidity, you've got to be itching like hell.

Don't know what that is but I'll take a look. If I couldn't use plastic for the transom I was going to at least add some in key places where screws always go such as bilge pump area.

Thanks. Yep, it sucks but it has to be done... I try to limit the grinding for pre-noon and after dark. Unfortunately I'm stuck at a party now but the break is welcome or I'd be out there now.

Have you seen Coosa Bluewater 26 board (coosacomposites.com)? I am going to use this on my USA 39. Got some samples from the manufacturer and man is this stuff stout! It is about the same cost as marine ply (when you add upp all the layers) but it is one piece and has 2 layers of woven roving built in. IMHO it is worth looking at especialy considering the lengths it looks like you are willing to go to. Good luck.

+1 on the plywood transom......... You have done a lot of work in a short period of time..... and ....I think the results will be worth the effort. As far as the transpm cutout profile, yes...that was the stock pleasure boat configuration.

Question....Did that transom have triples on it at one time?
If so can you figure out what the actual gel coat color was on the hull (looking at either beige or blue for a hint as to what boat that was).... If there were no triples it probably was the pleasure boat we put together for a dealer meeting we had at The Jefferson House. back in 1981.
I am traveling and looking at the pictures on a very small screen on my MacBook Air......

Rich, glad to hear from you regarding this project. The boat never had triples, only twins with a tunnel tab. Where there is white stripping, underneath it is actually gold if that helps. The boat was painted this way from at least 1987.

If you wouldn't mind I have a few questions/observations that maybe you can help me understand.

Is there a reason there are no stringers or knees? Granted, I'm 100% new to cat construction and maybe there just isn't supposed to be any.

There also was never a drain for the V in the tunnel...normal? I'm planning on adding one, plus adding left to right supports that run under the floor to add support to the floor.

Was the rear of the boat always cut out exposing raw balsa (under wood coverplates) or did someone do that when they rigged it for the v8's?

I'm adding jackplates, not because I think it needs it, but because when I can afford Merc 300's I dont want to have to redrill, etc... If I put the minimum setback of 4", how far forward should I move the tanks? I planned on 6" for not only center of gravity but also to give more room for knees..

Replacement balsa... Baltek???

Since people seem to prefer wood over a composite transom....the age old question... Exterior or marine? It appears that exterior was used for bulkheads.

Sorry for the questions but since I'm missing every nice weekend working on this thing I would like to make it right... Sorry about not much updates but I'm hoping by the end of this weekend to be finished grinding on the inside. I may give it a rest for a bit and start wet sanding the outside for a bit. I'm getting physically worn out.

One Idea you may want to consider. Instead of the Transom plywood (or what ever you use) goin all the way down to where the drain plug is, make it stop about 2" short. this way it can't "Wick Up" water and your transom will last considerably longer. the bottom of the transom/running surface are usually the thickest part of the boat anyway so it won't be lacking strength by shortening the wood. Do the same for the center V also.....