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Old 07-13-2010, 04:51 PM
CatBuilder CatBuilder is offline
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Demountable Mast for 45' Catamaran

Does anyone have any advice as to how to obtain a mast that can be lowered (temporarily) on a 45' catamaran?

The air draft of the boat is 65 feet of so (estimate, plans not open in front of me). The mast has a curve aft near the top and uses one of those fully battened mains, like modern cats do.

I'd like to be able to lower the mast to make it under low bridges, then raise it back up once inside somewhere. There is an enormous amount of shallow, protected and private anchorages behind low bridges in the world and I'd like to be able to explore these with me 1'8" draft.

What are the best systems?

I can imagine a pin in the mast and a pivot on that pin... other ideas?
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Old 07-13-2010, 05:03 PM
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hoytedow hoytedow is offline
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Put the mast on a pivot like an elbow so that the top,or palm, would face down over the stern as the mast was downwinched from the bow. The jib-stay could be the winch line holding the mast up until it is locked into place.
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Old 07-13-2010, 05:04 PM
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hoytedow hoytedow is offline
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Drawing I will do later.
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Old 07-13-2010, 05:25 PM
CatBuilder CatBuilder is offline
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Thanks, Hoyt.

Don't draw it yet though!

The mast would have to go down over the bow, winched from the stern because there is a deckhouse in the way aft of the mast. Also, I could put a nice little cradle in for it on the cross tube that connects the bows together, forward of the trampolines on cats.
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Old 07-13-2010, 08:59 PM
outside the box outside the box is offline
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Mast lowering system

Hi there
PM me as we have a system we use on our catamaran that might work.
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