Advice on transom , stringers and floor rebuild

[carlos515]

Would the white stuff be gel coat ? It seems to be mixed in with the chopped strands from the gun they used .

 

[Chris51280]

this is what i believe very loose chop strand. not sure why it is there? I had this between the transom and the plywood as filler. you want to see the pink thick woven as you have it there already. some hulls are thicker than others, make sure not to grind too deep. the bilge you show there has a gelcoat to finish. gelcoat has to go

 

[carlos515]

Thanks,
Just waiting for some 40grit disks to finish.

 

[carlos515]

Wondering if 1/2 inch ACX would be strong enough for floor. I was going to put 2 layers of 1708 on top . Or should I just get 3/4 ACX ?

 

[GSPLures]

Most replace what was there. If it was 3/4 stick with that. It would suck to finish glassing in to find out it wont hold up. If it was 1/2 then replacing with that would be fine.

 

[Scott Danforth]

depends on your span. the floor in my boat is 1/2" balsa with a bit more than 1/8" fiberglass on both sides. however the widest span is 36" and there are 1/2 x 1-1/2" ribs every 2 feet.

if you have a short span, 1/2" would be enough with 3 layers of 1708

 

[carlos515]

My span is 30" but no supporting ribs. The original floor was 3/4" but I was thinking to go lighter, But perhaps keeping it 3/4" would be better. Right now my suppliers for glass and resin are running short , and the lumber prices go up daily. As most repairs start out as a small repair....then as you delve into the project it grows to a large one.....
All in all this is a good learning experience , with lots of might as well's.

Thanks

 

[GSPLures]

My span is 30" but no supporting ribs. The original floor was 3/4" but I was thinking to go lighter, But perhaps keeping it 3/4" would be better. Right now my suppliers for glass and resin are running short , and the lumber prices go up daily. As most repairs start out as a small repair....then as you delve into the project it grows to a large one.....
All in all this is a good learning experience , with lots of might as well's.

Thanks

If you really want to go with 1/2 you can always add more structure. From a cost savings point it might not be worth it, and from a weight saving point that would depend with how much more structure is needed and with the extra glass weight included.

I had to run out and buy another sheet of 3/4 which prices are ridiculous. I paid $45 when I first bought it, this last one was almost $70. So I hear you about prices going up.

 

[Scott Danforth]

in about a month and a half the resin supply will be back up. Lumber will be back down lower in about 3-4 months

 

[carlos515]

Well after almost a month , I got some time to grind the bilge and transom. The gel coat was at least 1/4 inch thick. 4 hours later I have a good base for the new engine bay and transom. Does stitched mat have any strength , or is it just for binding the fiberglass cloth in layers?

 

[Scott Danforth]

yep, mostly for bilge gel, they poured it in the bilge and mopped it about with a roller

 

[88 Capri (2022 SOTY)]

Well after almost a month , I got some time to grind the bilge and transom. The gel coat was at least 1/4 inch thick. 4 hours later I have a good base for the new engine bay and transom. Does stitched mat have any strength , or is it just for binding the fiberglass cloth in layers?

The mat doesn't really offer strength. I am using 1708 bi-axial with poly resin which has a layer of mat on the back so no real need for additional mat in layering. I used the may to basically waterproof areas of the boat that didn't need additional strength like my seat boxes etc.

 

[carlos515]

Thanks,
Well I finished the grinding to tab in the stringers and transom. 8 hours of grinding and 30lbs of fiberglass dust. This is the first fitting of the stringers. I will throw a laser level on them to trim the tops. Originally I was going to put the new floor on the old floor tab in place. Would bring me up 3/4 inch. The original floor just sits on a chine and is tabbed in.

 

[carlos515]

Do most people tab the transom , then the stringers in? Then the bulk heads? Or everything at once?
I was thinking to tab in the transom first. then the stringers and last the bulk heads and ski locker floor.

 

[88 Capri (2022 SOTY)]

I tabbed my transom first and worked forward. I had everything laid in with PB prior to tabbing. When it came to stringers and bulkheads I did them at the same time working from the transom forward.
I removed my ski locker as personal preference but as others stated they kept theirs.

 

[GSX455]

You've got it setup well; stringers right up to the transom, I did the bulkheads last. I used 1" long pieces of PolyEthylene foam (used for floor tiles) spaced a foot apart as a spacer for the PB, PE won't dissolve the PE foam, it cushions the stringer from the hard contact with the hull.

 

[KJM]

You've got it setup well; stringers right up to the transom, I did the bulkheads last. I used 1" long pieces of PolyEthylene foam (used for floor tiles) spaced a foot apart as a spacer for the PB, PE won't dissolve the PE foam, it cushions the stringer from the hard contact with the hull.

I've heard a lot of people saying that about cushioning from the hull. Won't the space between the spacers still be full of PB and not cushioned? I can't see how that helps?

 

[GSX455]

I've heard a lot of people saying that about cushioning from the hull. Won't the space between the spacers still be full of PB and not cushioned? I can't see how that helps?

As long as you don’t have the entire length of your stringer bonded directly to the hull it’s fine. What you don’t want is to propagate a stress crack, that’s why the flexible spacers prevent the stress from going along its entire length
The chopped glass fiber in the PB also make the polyester less rigid. PE resin is very weak and needs to be reinforced

 

[carlos515]

When mixing PB does it matter if I use milled 1/8" fibers with my Cabosil or can I use chopped 1/2 " glass for my transom install ?

 

[88 Capri (2022 SOTY)]

I think you could use 1/2" but I used 1/4" and it worked great, from the reading I've done it seems most people use 1/4".
As far as milled fibers I used 1/32" to make my hull and deck putty but as far as transom install with it I'll let someone with more experience answer that part