Materials

[Andy74]

What resin/epoxy do I need for transom and stringers
1708 used on everything?

 

[Chris1956]

There are several weights of glass cloth, and a couple of different mat weights. I would recommend you go to a marine store and check them out, and see which has the flexibility and strength you want. Figure on 4 layers of cloth overlapping the hull by a few inches, to finish the inside or outside of the transom, plus cloth or mat between the plywood. Ordering online can save 75% or more.

Resin can be polyester laminating resin or epoxy resin. Your boat was made with the former.

I used some waxed gelcoat as the top layer, to seal and cure the polyester laminating resin, that I used.

Epoxy resin is stronger, slower to cure and much more expensive than polyester resin. Cure time for the polyester resin can be adjusted by adding more or less hardener. It is hard to speed up or slow down epoxy resin cure time. Both resins cure faster in warm weather.

 

[Scott Danforth]

Poly is used with 1708

Epoxy is used with 1700

 

[Andy74]

There are several weights of glass cloth, and a couple of different mat weights. I would recommend you go to a marine store and check them out, and see which has the flexibility and strength you want. Figure on 4 layers of cloth overlapping the hull by a few inches, to finish the inside or outside of the transom, plus cloth or mat between the plywood. Ordering online can save 75% or more.

Resin can be polyester laminating resin or epoxy resin. Your boat was made with the former.

I used some waxed gelcoat as the top layer, to seal and cure the polyester laminating resin, that I used.

Epoxy resin is stronger, slower to cure and much more expensive than polyester resin. Cure time for the polyester resin can be adjusted by adding more or less hardener. It is hard to speed up or slow down epoxy resin cure time. Both resins cure faster in warm weather.

What do you mean by my boat was made by former ?
Thanks for the information much appreciated.
Not to many marine shops near me there about an hr each way. So hopefully someone can help me out on what I should get. I have a 93 19’ Larson open bow 4.3 merc

 

[jbcurt00]

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[Chris1956]

Andy, I simply meant that your boat (and the vast majority of boats) are made of polyester resin, plus cloth and mat of the appropriate weight.

Cloth comes in 1.5oz, 3oz, 4oz, 6oz, 7oz, 8oz, up to 40oz. Weight is per sq yard.

Heavy roving cloth comes as 18oz, 24oz. Weight is per sq yard.

fiberglass Mat comes in 1oz, 1.5oz, and heavier. Weight is per sq foot.

I would visit a store and feel the cloth and mat to determine what seems like the correct weight. Heavier cloth does not turn corners as well as lighter cloth, but is much stronger.

 

[Andy74]

Andy, I simply meant that your boat (and the vast majority of boats) are made of polyester resin, plus cloth and mat of the appropriate weight.

Cloth comes in 1.5oz, 3oz, 4oz, 6oz, 7oz, 8oz, up to 40oz. Weight is per sq yard.

Heavy roving cloth comes as 18oz, 24oz. Weight is per sq yard.

fiberglass Mat comes in 1oz, 1.5oz, and heavier. Weight is per sq foot.

I would visit a store and feel the cloth and mat to determine what seems like the correct weight. Heavier cloth does not turn corners as well as lighter cloth, but is much stronger.

Thanks Chris
In my boat it only has 2 stringers and they are glassed on one side tabbed in. I think that was poor quality and transom was not glued or glassed together very well. Hurry up and get it done! Lol.
I’m going to make it better have a lot of work ahead of me

 

[Chris1956]

The hardest part is to find a way to clamp the transom to the hull, while the resin sets. I glassed some pressure treated lumber to the hull, along the deck, and just under the splashwell, so I could screw the transom to the hull, after the glass was wetted out. I also installed the transom from the outside. If you can install from the inside, keeping the original glass on the outside, that would be better.

 

[Andy74]

The hardest part is to find a way to clamp the transom to the hull, while the resin sets. I glassed some pressure treated lumber to the hull, along the deck, and just under the splashwell, so I could screw the transom to the hull, after the glass was wetted out. I also installed the transom from the outside. If you can install from the inside, keeping the original glass on the outside, that would be better.

 

[Andy74]

Yeah I will be able to clamp it in and/or wedge star and port sides
I seen a guy expand the whole transom and a way to clamp so I’ll more than likely do it his way

 

[Andy74]

So if my boat came with a 4.3 merc can I put a v8 in it later if I decide to?

 

[Scott Danforth]

So if my boat came with a 4.3 merc can I put a v8 in it later if I decide to?

if you have the room and you change the drive ratio, and your mount beds are 4" longer than the 4.3

 

[Andy74]

if you have the room and you change the drive ratio, and your mount beds are 4" longer than the 4.3

Well never mind that I’ll just stick with the 4.3
Lol no need for more work

 

[JASinIL2006]

I believe my Larson (a ‘97) was originally outfitted with a 4.3L Volvo Penta that later was replaced with a Mercruiser 350 Mag (basically a 5.7L V8). At least on my ‘97, a 5.7 was an option when the boat was built, so other than some shims under the front motor mounts, there was no modification needed. Yours may be similar.

You can check out my restoration thread (see link in my signature below); it may help you some. Larson made changes in how they constructed boats in the mid-90s, though, so yours likely is somewhat different.