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Bryan B
 
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Default extending rigging wires

I will look into a drilled/tapped/bolted fitting.
If you go this route you may want to also epoxy your gooseneck in place.
It helps with corrosion and provides strength.


Has anybody ever seen a reinforcement inside the mast at a gooseneck?

No, I have only seen boom vang locations and shroud locations reinforced
but I'm sure haven't seen it all.


"Evan Gatehouse" wrote in message
...

"Glenn Ashmore" wrote

Synthetic rigging seems to be big with multihulls these days. Precourt
in Canada http://www.precourt.ca/ makes deadeyes up to 30,000 lb. just
for that purpose machined as chainplates, middle eyes and top thimbles.


yeah, that's the lanyard/deadeye's I would use. The stretch on short
lengths would be o.k.

You might even consider replacing all the rigging with Amsteel Blue. It


Yeah, but Eric Precourt doesn't recommend using it with fixed rigs (which
this boat has). Too much stretch compared to wire; it's o.k. with 3 stay
cat rigs where the mast rotates and you want a little slack.

What I want to know is how do you intend to raise the mast off that deck
beam and what will it do to the RM? You are increasing the lever arm of
the center of force and putting it up higher into stronger wind. That
in combination with reducing the angle of the stays will increase the
load on the stays. But maybe the wide base of a cat will minimize that.


Well I'm only raising it 2' - I'd certainly do the calcs but as a

percentage
it isn't much. Extending it would be as simple as a little 2' aluminum

pipe
compression post with welded flanges on either end.

Jim Conlin wrote:
The added accommodation will substantially increase the weight of the

boat,
increasing the righting moment. Is the existing standing rigging up to

the
increased loads?


Yes, it would increase the RM - but the overall boat + payload weight is
still within the designer's maximum number.

freddy said:

Go back to the designer and ask the proper questions - there's lots of
aspects to this question besides rigging.


True - but I'm pretty capable of handling those , it was just this
particular aspect that was something I didn't have experience with.

Ford Walton wrote:

Lanyards and deadeyes" or solid metal extensions should work, but you
could also cut 2 feet off of the top of the sail and add a short gaff or
a really substantial headboard.


I did think of just chopping 2' off the head of the sail after raising the
boom (but I want to preserve sail area).

Jim Woodward had a lot of good points especially the super turbuckle but
I'll address this one:

6) If you decide on the second solution, "just reweld the gooseneck 2'
higher", consult with the mast manufacturer. Many masts are made from
heat treated alloys that shouldn't be welded after heat treat and
there may be reinforcement inside the mast at the existing gooseneck.


Almost all masts are 6061-T6 which is a heat treated alloy that loses
strength after welding - but the existing gooseneck flanges are welded on
and seem o.k. - so another weak area 2' higher probably isn't going to
cause too much trouble. I will look into a drilled/tapped/bolted fitting.
Has anybody ever seen a reinforcement inside the mast at a gooseneck?

I've
looked up a lot of mast tubes and seen a lot of mast drawings and never

seen
one on an aluminum mast.

Once again thanks for all the constructive thoughts. They are

apprecicated.


--
Evan Gatehouse

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ceilydh AT 3web dot net
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