Fruits Of My Labor (A-113)

[ebb]

Well, Cappy, it's like this:
Noticed these same shadowy indent on 338 also. Certainly not scars! You can see them if the light is just right, but it's easier to feel them on 338.

Let's take those stringers: they are 1 1/2" wide, not 3/4", with a bunch of poly and mat tabbing them on. They are not under load like a bulkhead yet they've telegraphed thru the hull somehow.

I have not read any literature on this phenomenon.

The imprinting you read about is what happens when you place a hard edge against a thin, THIN, 'engineered' modern hull. You would put in a pillow to spread the load with filleting and tabbing, suspending the sharp edge of the bulkhead off the hull.

IMCO, you don't have to do this on the Ariel. If you think your old stringers, described above are imprinting then you better put in 10 inch wide styrofoam between the bulkhead and the hull. Correct?

338 has and will have all its plywood bulkheads put in dry, with large, 1 1/2" fillets (90 degree radius fillets take very little gel.) Then on major bulkheads two or three layers of mat with the narrowest put in first. This I believe widens the loads out even more. And the HOLD on the hull can be spread out as wide as you make your tabbing. At the compression bulkhead I would tab over the fillet 4", then 8", 12", 18". Well., something like that.

What arguement could there possible be that if both sides are done this way that anything is going to move? Maybe the boat will shrink! And thereby reveal the bulkhead?

Suspended bulkhead on foam? The upward pull of your upper shrouds is going to be opposed by your tabbing which is spread fairly wide on your hull. Maybe that's ok. Maybe I'ld add more tabbing.

If I remember 338's stringer imprint on the hull outside is slightly holloiw, ie there are two mini ridges. Of course the hull is thinner up there, and the imprint is lengthwise. Maybe the hulls weren't cured all the way when they added these things when they made them.

Would very much like to read anything on the subject of fiberglass boats changing shape, shrinking, becoming brittle (not gelcoat.) pre-OPEC oil crises (1973.) We get surface delamination from sun and heat, but shape-changing so that pasted on interior pieces would 'imprint'? On the Ariel, I don't think so.

What they did: they slapped the stringers on loaded with extra hot catylist. Braced them up with spring battens and let them smoke. On a not yet totally cured hull, That might cause distortion. I think it all happened at the factory. ARGUEMENTS?