started repair on wet transom

[Don S]

Re: started repair on wet transom

I would like to know what kind of stringers they are called with out wood just fiderglass and foam

They are called "stringers". Just like any other one. The manufacture of your boat and several others use the fiberglass and foam as the complete stringer.
It's just how they designed them.

 

[joseph L]

Re: started repair on wet transom

Hi oops:

I looked at u tube link and saw the seacast for transom and stringers. The manufacture designed the stringers that way.

Thanks for all the information.

Also thanks Don S for all the information.

Joseph L.

 

[Coors]

Re: started repair on wet transom

Many stringers are made of wood/foam being the form to glass over.
If that is the case, of having the fiberglass casing-cut the top of the casing off, dig out the rotted foam and wood (make sure the hull is supported).
Once you have done this, and reached nirvana, cut and install another board, and pour epoxy into the existing form. Done
Then say, never again will I do this.

 

[drewmitch44]

Re: started repair on wet transom

Hello all, Im restoring a 21.5ft 1979 Fiberform sportsman. The stringers were made a little differently in this boat and I am replacing them. Originally they were plywood incased in fiberglass on either side of a bottom fuel tank. With a piece of plywood layed over the tops on either side, fiberglassed over, filled with flotation foam, and a molded fiberglass floor insert resting on the transom box and attached to the rub rail. It seems the fiberglass gave most of the strength. I do not wish to use plywood agian. My Idea is to take closed cell foam (The 4X8 blue sheets at Lowes and Home Depot), use liquid nail to sandwich the foam with 1/8 inch pine or fiberglass wall covering (the 4X8 pannels sold in the same locations), sealing the ends with paint or RTV, and then fiberglass over them. Since the foam melts in contact with resin, the wood or roughed up fiberglass and pained ends would act as a barrier and would considerably strengthen the foam. This would be laid out as a box and filled with floatation foam. Anyone ever try this? Do you think its a good idea or just rubbish? I know the fiberglass alone is strong enough because i ran the boat when the stringers were mush and there was no flex whatsoever. Any suggestions would be appreciated. Thanks.

 

[joy]

Re: started repair on wet transom

Drew I know the insulation board your talking about, we use it in our excavating business to go under radiant tubing under concrete and other applications. Its quite brittle, I wouldn't use it to frame (thats essentailly what where doing here) the boat. Another thing you should know about that stuff is, it is light sensitive. Too long of storage out in the sun destroys its integrety. Just my opinion though, feel free!

 

[joseph L]

Re: started repair on wet transom

pouring transom [http://www.shareaproject.com/projectThumbs.php?p=462

 

[SFT2]

Re: started repair on wet transom

With foam cored composites, it's not the foam that gives the strength, it's the glass. The foam helps some with bending, but it's mainly there just to give the shape to the glass. The blue and pink foam found in building supply places is the wrong stuff to use for cores. It's not dense enough and, as noted before, vanishes in the presence of polyester resin. Epoxy is safe with it, but the density is still wrong. The best bet would be urethane foam cut to shape and bedded into place with thickened resin, then encased in glass cut on a 45 degree bias. Very important to break the corners of the foam before glassing, a 1" radius will work both on the top edges and the corners at the joint between the hull and foam. Composites hate sharp corners. I need to do the engine mount stringers in my Baja this fall when I swap engines, but I can't get away with foam cores, unfortunately. I need the wood to hold fasteners, and I'm entirely too lazy to engineer a foam core with wood inserted to hold screws If I decide to go with a bed-type mount that bolts between the stringers I may be able to get away with stainless sleeves through the stringers, but that's a decision to be made much later.