Stringer question

[CSX]

Do soft chine sailboat hulls need stringers?
I have been looking at many builds and restorations and I haven't been able to find any good examples.
Does it depend on the laminate thickness if they are installed or not?
Thanks

[gonzo]

Are you talking of fiberglass? Stringers may or not be used. Often, the interior cabinetry takes the place of stringers.

[CSX]

Yes fiberglass, and single skin.
I have seen builds out of plywood that is fiberglassed over that incorporate stringers but not any single skin with fiberglass or other stringers.

The reason I am interested is I worked out the scantlings for my boat, and 5 stringers per side and 5 bulkheads are the requirements, however the glass layup is over twice as thick as the scantling calculation. So I was thinking the glass or hull thickness was the reason the soft chine don't have stringers like other builds?

But the cabinetry would make sense to

[gonzo]

The scantling calculations are for a particular building method. Each method ends up with different scantling for each part of the structure.

[CSX]

Thanks Gonzo.
I used Gerr methods for Fiberglass solid-glass hull shell.

Is it realistic then to take these rules and apply them to an existing boat that was designed by engineering methods or others and not scantlings or this specific set of rules?

The purpose would be for an Internal structure rebuild, or additions.

[gonzo]

You can study an existing structure, mainly to see if it was build strongly enough. However, you need to use the same method. Also, the boat has obviously lasted quite a while. I would say the scantlings are fine. You may ruin a boat by changing major structural parts.

[CSX]

Yes that sounds good to me, would an accurate description of these hulls be monocoque with the loads being spread around the skin and deck structure?
There must be something that was done right for a hull to last 36 years without defect.