Foam or epoxy under stringers?

[Jeff_40]

I’m rebuilding my 1974 Starcraft american 15 and was planning on laminating all 3 stringers then wrapping them in cloth. I was curious if it would be better to build the stringers and then just drop it inside the hull? Or put each length of wood in piece by piece? I have heard that I should put a layer of thickened epoxy under the stringers or use foam as it’s not good to have the stringers right against the hull? Not sure if this is true or not but any advise would be appreciated as this is my first project thanks in advance. The second picture is what it looked like before I removed the foam and wood and grinder everything down

 

[AShipShow]

Holy worm food! Those stringers were in bad shape!

You read correctly, it is recommended to leave a small gap between the stringers and hull (about an 1/8" or so). You can use foam pieces or anything soft really... Then bed your new stringers in thickened resin and filet the squeeze out to give yourself a nice radius for tabbing. Personally, I would make the entire stringer outside of the boat, its easier to work on a table than in a hull.

 

[Grub54891]

I built mine first.

 

[kcon]

I built mine first.

I did exactly this as well, once I had mine shaped well I screwed them all together and used blocks to hang them evenly over the hull, then I filled the gap with PB epoxy, really made keeping the stringers/bulkheads level and even quite simple.

 

[Redtruck12]

K con
nice looking work.
what did you use for drain tubing?

are you planning drains from outboard of the stringers?.

 

[kcon]

K con
nice looking work.
what did you use for drain tubing?

are you planning drains from outboard of the stringers?.

For drain tubing I epoxied in stainless steel 1" pipes at the lowest portion of the bulkhead. I didn't add drains to the left/right portions of the boat outside the compartments/stringers because I made those sections 100% air tight, then drilled a hole on each side, poured foam, and sealed it all off. I used a tremendous amount of epoxy & epoxy PB to assure these compartments will remain air tight for a long time, should that be compromised in lets say a decade, I'm not too worried as naturally any water that enters the boat flows over the deck to the center, which I imagine would buy me another 5-10 years of unsaturated foam.

I don't wanna cake up another guys thread with my pictures lol, if you're interested I have a lot more pictures/explanation on the thread linked in my post footer signature below, just about done with er.

 

[Goldie627]

i used sticky back clear stand offs to create the gap between the floor and the stringers, the sticky back helps keep the stand offs in place while you place the next one. got them from HD

its also kinda cool because they stay in place while you lay down your peanut butter

 

[sheboyganjohn]

I bedded mine in PL. I put down a stack of popsicle sticks in a few spots to hold the stringers up then filled under them with the PL avoiding the sticks. Once the PL set up I pulled the sticks out and filled in those spots with PL so it would be completely sitting on the PL with no gaps. Once it was all set-up I came back with peanut butter and filled in the radius, then started the glassing and so on.

 

[JASinIL2006]

I think Goldie's idea is really clever!