1984 Wood Catamaran Advice

[smj]

Originally Posted by Manateeman

Herbert J. Ashcroft was a great boatbuilder and is credited with the invention of the double diagonal planking method for building wooden round chine hulls.

He wrote a book Boatbuilding Simplified. The technology of glue laminated wood hulls was known in China before the Portuguese arrived as they make mention of this in numerous journals. China constructed a huge military fleet with multi mast vessels exceeding the size of British, Dutch or Spanish ships of the line.

A new Emperor burned the entire fleet and China closed its doors.

Ashcroft planks were laid parallel. Later cold molded boats were laid cross hatched as in a radial tire. It became the west system with little credit given to Ashcroft. Urea formaldehyde and resourcinol glues were used earlier before epoxy. Worked fine if you maintained the boat.

Howard Hughes used rice paper in the Spruce Goose which was almost all birch wood. Clearly a very strong method of construction. It is not similar to balsa core in a structural manner... at all. Neither is it similar to stitch glass fabrics. Balsa is a wood and water is a solvent. It’s important to keep laminated wood dry and it’s important to keep balsa dry but the two construction methods are as different as night and day. When balsa gets wet, the rate at which the entire laminate looses strength is much, much faster than Ashcroft even if you built out of common pine and yellow wood glue. Why anyone would use balsa is beyond me when honey comb cores in everything from plastic to aluminum, are available.

SMJ has a boat which is light and strong. He has an excellent point.

It’s just sad that he lacks enough beer drinking manatee friends to pile up enough cans so he could weld himself up an aluminum hull. Or two. Till then,

Happy trails to you.

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Who needs the beer drinking manatees when the captain has a healthy appetite for Budweiser! Though I will happily eat pizza and drink beer with you, your lovely wife and your herd.[emoji23]

[sdowney1]

The blackened wood does not look like rot to me, some kind of staining it is, maybe due to iron. Mahogany will eventually rot, if it is exposed to fresh water. Otherwise wood can last a hundred or more years.