stringer replacement

[stevewaz]

replacing all stringers in a 17ft seaway - want to do job top shelf - will fabricate 2x stringers out of 3/4 plywood then seal with epoxy before installation

1. marine plywood or AC fir or ?
2. bow to stern stringers need to be 10ft - will overlap pieces to get this length - is this ok?
2. should bow to stern stringers be bedded to hull in epoxy? could not tell if old ones were
3. how many layers of fiberglass cloth tabbed to hull over stringers?

 

[proshadetree]

Re: stringer replacement

I would do in marine plywood.Bed to hull with thickened resin sawdust works to thicken it up. 2 layers should be fine.Check out f-14s thread for a first class job and some great picts.

 

[92excel]

Re: stringer replacement

marine ply is better if you want to spend the money but exterior ply is perfectly fine to us.

To get your 10 feet you can do a lap joint.

they definetly need to be bedded to the hull.. none of the wood should come in direct contact with the hull.. the bedding material is up to you.

number of layers depends on the weight that you are using. I used two layers of biax. so thats about 48 oz in total.. i beleive biax is 24 ozs.
the biax does like to wrap over the top of the stringer.. so i capped the top of the stringers with 4 layers of CSM.

 

[danond]

Re: stringer replacement

If you're using epoxy resin the required amount of both fiberglass and mixed resin goes down. Epoxy is like steel. Love the stuff. Doesn't mean you can't put on more layers, but it's something in the neighborhood of 4x stronger than polyester.

I'm not a believer in marine plywood being an advantage. If you do your boat right, and you probably will, you're sealing the wood completely, anyway. I prefer exterior grade as there's no dry-time and no worry about warping as it dries.

 

[F14CRAZY]

Re: stringer replacement

personally for my Capri the original encapsulation was an average of 3/16'' so I used three layers of 18 oz fabric with epoxy