Stringers: Is the Structural Strength in the Laid Up Fiberglass or the Core Material?

[carolina_angler]

Ok here's one to pick your brains!

Does the structural strength of a Stringer belong to the fiberglass shell made from lapping many layers of fiberglass over a wood, foam, coosa-board, nida-core, pvc, or honeycomb core? or does the structural strength lie in the core itself?

Here's the hard part ......no taking the easy way out and saying "both"!

And .......does the shape matter? square cornered or rounded top?

And so the debate begins.......

 

[Woodonglass]

There is no debate. Been discussed and determined long time ago here on the forum. It's all about how the stringer is constructed. If it's wide and made from multiple layers of glass. (1/4" thick or more) then the core material is really not important, it really just acts as a mold for the glass. If it's comprised of only one or two layers of glass then a structural core is required with a filleted base to help broaden the base to distribute the load along with extending the glass out on to the hull 4-6 inches. The link in my signature will give a lot of information on Stringer construction.

 

[carolina_angler]

Well said "Woodonglass" and I tend to agree with you ...your value of experience is priceless......I'm trying to glue together a multitude of fragments of web information.
I think the cumulative thickness of the glass, type of glassing material, and the reach of distance bonding the stringer glass to the hull is the key

 

[tpenfield]

You also posted this on THT ???

 

[carolina_angler]

Yes I did TP trying to source as much info as I could .....if multi-posting is not allowed my apologies

 

[jbcurt00]

Don't fall victim to paralysis by analysis. If you spend more for perceived higher 'value' materials that cost more, it's not necessarily going to yield a significantly 'better' product in the end, it'll just be a more expensive project.

If you don't maintain a boat, it'll still fall victim to water intrusion & rot unless you are going to replace all the boat structural wood w/ man-made materials. And then you'll still need to add flotation foam, which won't be any different then what's below a wooden deck if it ever gets & stays wet.

Are you building your own boat, rehabbing the last boat you'll ever own, or just want the information for informational purposes only?

 

[carolina_angler]

Thanks Jb
am rebuilding a boat cap off restoration and "dead set" against using any wood + using the best possible floatation foam
leaning toward coosa board transom and transom braces with nida core floor deck and possible foam filled stringers with structural stringer strength based on the fiberglass casing around the foam stringer cores ....your thoughts? what foam would best suited to poly e or poly v resin?