Sportcraft tri-hull rebuild

[eaglejim]

Re: Sportcraft tri-hull rebuild

Well today was a good day to finish taken out foam and some more soggy wood,now I think I need to belt sand or grind the rest of the transom

So which should I use marine plywood or regular plywood

One of the guys helping me wants me to paint it while we got it in two pieces and I know this is getting ahead of myself but what is the procedure.So you all know I am a house painter by trade so the tools won't be a problem

Will also need info on fiberglass in a while,Thanks for the help

 

[electric603]

Re: Sportcraft tri-hull rebuild

It is hard to tell in the picture but do those stringers have glass on them? It is shocking to me that they are still solid. The stringers in my '72 were so saterated I was squeezing the edge and water was coming out. The glass work was laughable. I will be following your restore as I am restoring mine now too. But you already have more done than i got done all summer.

 

[eaglejim]

Re: Sportcraft tri-hull rebuild

Yeah electric the stringers do have glass on them and they are solid I drilled holes (4th post) at the bilge so any water in the future would go where it was supposed to go I thought I would need to replace the stringers but to my surprise so far they look good (until someone says different). I also have a good supporting cast of characters by trades house painter(me) carpet installer(his fork truck and place where we work on it) a minuteman press guy(walking buddy) and a computer dude(the smartest out of us all).
The boat is a "77" with an "87" motor on it it is the kind of boat that my Dad use to take me when I was a wee one bought it for 300 and put 1200 in it 4 years ago and she seemed to be a little heavy this year so at the end of our season said to mrseagle that we needed to do this so here I am learning how to rebuild a boat and surprising so far it has been fun

 

[eaglejim]

Re: Sportcraft tri-hull rebuild

Ok guys my first of many decisions need to know what you all think,I was talking to an old salty dog (boat re builder) need less to say he gave me a lot of info I have be reading about pressure treated vs marine vs regular 3/4 plywood and he (salty dog) says to use the pressure treated he says stand it up for 2 to 3 weeks to let it dry out than I would be able to fiberglass over it.I read somewhere on this site that the pressure treated would be a problem with the glass I do have a place to store it so it can dry out so that is not a problem and I have other things to do on the boat,thanks for the input

 

[electric603]

Re: Sportcraft tri-hull rebuild

I also paid 300 for mine. The engine could not get spark. I was hoping it would be a quick fix and have it in the water. Then I discovered the rot. I was hoping to have the grinding done before I wrapped it for the winter but I did not get that far. As far as wood choice there are a lot of varying opinions. I am going to use exterior grade aB/C plywood. I think if it is fiberglassed properly it will last another 30 years. But i am no expert just MHO.

 

[jbcurt00]

Re: Sportcraft tri-hull rebuild

If you can afford (find) Kiln Dried pressure treated plywood, by all means use it. But it doesn't allow for less of any of the other steps of prep & covering the plywood w/ polyresin & glass.

Non-Kiln dried pressure treated can take a long time to dry to a low moisture level. As it dries, it will want to warp & twist, at least usually it does. Look thru the pile of PT plywood at the lumber store, there will be many sheets other's have deemed unuseable they are so misshapen.

Most can't find Kiln dried or justify the extra expense..

 

[Woodonglass]

Re: Sportcraft tri-hull rebuild

Here's the deal. Regular ext. Grade plywood used the exact same glue as does Marine grade. The two major differences in them is 1.) Marine grade usually uses more plys and of a better grade of material than ext grade and 2.) Marine Grade will have almost NO VOIDS in the plys. Typically Treated plywood uses fewer plys, and they do have voids. Arauco Ext Grade plywood has 7 plys with very few voids and IMHO is excellent material for Boats. If properly prepped, Glassed and maintained stringers, decks and transoms fabricated from it, will last for decades which is prolly longer than you will have the boat. I see no need or value in using PT plywood in boat restoration. But I am just an

 

[eaglejim]

Re: Sportcraft tri-hull rebuild

Thanks Woodonglass I wasn't really looking forward to using PT the boat is 35 years old and the best I can tell this is the first time the deck has been replaced and if I can get another 20+ years out of this deck and transom I am good with that thanks for the info.Jim

 

[eaglejim]

Re: Sportcraft tri-hull rebuild

Well I sanded the transom down again,removed a bad stringer and washed her down

That was bad stringer at the bilge

Tomorrow scrape any left over foam and vacuum,cut new stringers make a template that is if mrseagle doesn't have other plans

 

[eaglejim]

Re: Sportcraft tri-hull rebuild

Here's the deal. Regular ext. Grade plywood used the exact same glue as does Marine grade. The two major differences in them is 1.) Marine grade usually uses more plys and of a better grade of material than ext grade and 2.) Marine Grade will have almost NO VOIDS in the plys. Typically Treated plywood uses fewer plys, and they do have voids. Arauco Ext Grade plywood has 7 plys with very few voids and IMHO is excellent material for Boats. If properly prepped, Glassed and maintained stringers, decks and transoms fabricated from it, will last for decades which is prolly longer than you will have the boat. I see no need or value in using PT plywood in boat restoration. But I am just an

Saw what you were talking about with the pw wood thanks for the info

 

[electric603]

Re: Sportcraft tri-hull rebuild

Eaglejim, I think our hulls are identical except they did a much better glass job on your stringers and your topcap is a bow rider and mine has a deck up front. Mine is supposed to be a '72 maybe they learned how to lay fiberglass in those 5 years. Check out my thread you can see the horrible glass work they did on thestringers.

 

[electric603]

Re: Sportcraft tri-hull rebuild

Does your hull have a hook toward thetransom? Mine does and I'm not sure if it was built like that or did it develop from sitting on bunks that were too short and with rotten stringers for who knows how long.

 

[eaglejim]

Re: Sportcraft tri-hull rebuild

Eaglejim, I think our hulls are identical except they did a much better glass job on your stringers and your topcap is a bow rider and mine has a deck up front. Mine is supposed to be a '72 maybe they learned how to lay fiberglass in those 5 years. Check out my thread you can see the horrible glass work they did on thestringers.

Yes my stringers are in pretty good shape had to replace a couple and the only difference I see is the bow rail

 

[eaglejim]

Re: Sportcraft tri-hull rebuild

Ok guys we finally got some better weather and was able to work on the boat today,made a template for the transom and the bow today HD carries the Arauco exterior plywood but of course it is a couple of towns over so hopefully I can make some time to get there .
The question is after I repair where I cut through the fiberglass taking out the deck should I put the transom and deck in then flip it over to paint the underside or flip it over after the repair and then put transom and deck in.Thanks for your input

 

[denlynn36]

Re: Sportcraft tri-hull rebuild

I watch your thread but see no reply to your question.. which is a good one. I dont know but I would think you would want a nice strong transom in at least before you try to flip... ?

Good luck!
Den

 

[Woodonglass]

Re: Sportcraft tri-hull rebuild

I'd get it all in before the flip. Stringers, Transom and Deck. A little heavier but... No worries about flex etc. If you got 3 buddies and a case of beer you can flip her really easy.

 

[eaglejim]

Re: Sportcraft tri-hull rebuild

I'd get it all in before the flip. Stringers, Transom and Deck. A little heavier but... No worries about flex etc. If you got 3 buddies and a case of beer you can flip her really easy.

I have a fork-truck LOL thanks for the advice just got the wood for the deck and transom went with the Arauco plywood,another small question we are going to cut it out tomorrow (Saturday) I think I read that we should make 2 of the transom and epoxy them together just wondering if that is what I read. I will try to go thru some old post to make sure and as always thanks for all the advice Jim

 

[eaglejim]

Re: Sportcraft tri-hull rebuild

I watch your thread but see no reply to your question.. which is a good one. I dont know but I would think you would want a nice strong transom in at least before you try to flip... ?

Good luck!
Den

Den thanks for the input we went from a transom and deck replacement to a paint the boat (while we are at it).

 

[jbcurt00]

Re: Sportcraft tri-hull rebuild

The old transom should have been 1 1/2" thick, so if you bought 3/4" Arauco, then yes, you'll want to cut & glue 2 pieces together.

WOG's signature link has some helpful details:
"Fabricating Decks, Stringers, and Transoms"

 

[tallcanadian]

Re: Sportcraft tri-hull rebuild

Good looking boat, jIm. Sorry I didn't see this before. Great job so far.