The Hull Truth - Boating and Fishing Forum - View Single Post - Opinion on transom core thickness. 1.50" or 2.25Ē?
Old 02-09-2019, 04:18 PM
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I would look at the overall panel span to determine thickness. Just shooting from the hip and it being a catamaran with a comparatively small transom area two layers would probably be sufficient with proper lamination.

Originally Posted by tunnles View Post
one thing that nearly everyone forgets about is shape !!
introduce shape into something you can triple its ridged strength
its so simple its stupid !!
Stupidity is relative. There is a difference between stiffness and "strength" (as you call it) introducing shape Into a panel doesn't make it any stronger. But it will make it more stiff.

Maybe (rigid strength) is stiffness?
Aren't you the big proponent for flexible is better???

Originally Posted by Tossedabout View Post
I agree with every. Only thing I add is a layer of 1700 between each piece of ply. Iím tired of hearing about coosa. You couldnít give it to me. Encapsulated meranti and no screws ever added. It WILL last atleast 40 years. By then Iím dead donít care.
2-3/4 plys or 3- 1/2
​​​​​​​check out classicmako for good tips.
I am no fan of coosa myself. And I wouldn't see any reason to advocate laminate between the layers but, Transom core is a funny thing. Plywood will rot if its compromised, but a high percentage of the overall strength is supported by the core itself. couple that with its compression strength its hard to beat for the cost.

Composite panels don't rot. But they really don't perform as well in compression. You increase the laminate but many times the force of just tightening engine fasteners can compress the core. The result of this is the laminate skin's that you are relying on for strength become compromised.

As for a solid glass transom. I dont see a problem. But to argue that a solid glass laminate will out perform a properly executed sandwich panel..and be lighter?

Well....that's questionable

Last edited by kln; 02-09-2019 at 04:55 PM.