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Post by Barr Avel on Apr 27, 2007 7:42:45 GMT 1
I want a small bowsprit to push the foot of my cruising chute further forward so that it clears the furling gear (at the moment it catches on it when I try to gybe.
Considering it only ever gets an occasional outing in very light winds, do you think I can use a piece of wood for this, or do you think I should get one done in stainless steel?
Also how would you recommend attaching it? It could lie on the spare bow roller, but I haven't worked out how best to stop it lifting with the sail...
Marc.
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Post by petecooper on Apr 27, 2007 8:13:08 GMT 1
On boats with assymetric spinnakers they usually have an extending bowsprit. As the bowsprit is not fixed they do not have a traditional bobstay, so the pole itself must be quite strong. What about trying something like a cut down wind surfer mast tied in place initially and if that works then consider a more elegant fastening method? Possibly a couple of loops bolted through the deck with the pole sliding through them?
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Post by Barr Avel on Apr 27, 2007 8:23:02 GMT 1
Thanks Pete, that sounds like a goog idea, I hadn't thought about a cut down windsurf mast. Now the next question is, where can I pick one up? Not much windsurfing aournd Portsmouth is there?
Marc.
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Post by mirelle on Apr 27, 2007 10:05:06 GMT 1
Whilst getting the tack clear of the headsail roller by two feet solves that problem, there may be an advantage, from the sail trim point of view, in getting it a bit further outboard than that.
You certainly want to keep weight out of the bow, so the idea of using a carbon fibre tube is a good one.
However, there might be a snag. My friend, the late Ian Wright, used a old carbon fibre windsurfer mast as a topsail yard on his gaff rigged Vertue, "Patience". He commented that they are made to be quite bendy, therefore I wonder if one would stand up to the job as a bowsprit for a cruising chute? Might want a bit of stiffening up.
I would think that it would not be too hard to make the sort of bowsprit launching chute that modern racers have by glassing in a length of drainpipe under the foredeck.
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Post by Barr Avel on Apr 27, 2007 12:04:37 GMT 1
Hmm the bendiness is a good point. I use a spinniker downhaul to attach the foot of the sail so that may stop it bending upwards, but it wouldn't stop it bending sideways.
Drainpipe also a good idea. I remember seing some very thick type of drainpipe somewhere which appeared to be very rigid... will look it up.
Thanks Mirelle & Pete for the suggestions!
Marc.
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Post by petecooper on Apr 27, 2007 12:27:30 GMT 1
If you see a modern boat with an asymmetric the pole does bend considerably without breaking and I thing that they are usually made from carbon fibre. I think that is what some windsurfer masts are made from.
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Post by NigeL on Apr 27, 2007 18:13:59 GMT 1
My w/ender - I know is a lot smaller - but has a 3 x 4 square section wood sprit tapering to about 3" diam at outboard end. It has full forestay on it ... so takes strain of mast and sails.
It has the standard chain to lower stem ring to counter vertical pull - which rarely stresses it in fact. The sprit is coach-bolted through foredeck.
Now the above has led me to consider a sprit on my bigger boat .... and the Hoop idea is what I considered - as I would want to reduce my length for any silly charges that might occur in Tallinn etc. So there is nothing to stop a chain affair to stem eye low down .... when sprit retracted that chain will be slack and accessible by hand from bow. Clip it to keeper OR leave connected so not forgotten when sprit slid out again.
Most people consider the vertical UP force on a sprit - but often forget about the vertical DOWN force at other end. Remember that a sprit is actually often pivoted on the fwd stemhead ... due to the "fastening".
Ok - another aspect - all know that they should get the sail tack part as near C/L as possible - but an inch here or there is not so critical ... AND you can offset the inboard end so that it is angled past the stemhead fitting (roller) and outboard end then is centred.
For my old tub ... I'm looking at a 4" square pine or elm post, basically best fence post I can find !! About 3ft extension to bow and about similar coming back onto foredeck. "Corners" will be rounded off to create a nice section but keeping as much strength as possible. I consider 2 sets of L brackets - that is L bracket either side of sprit at two places ... the brackets extending just above sprit so that pins can be put through to hold sprit down. Possibly the after actually being through sprit to keep it extended or retracted as applicable. A 2 fold tackle from outboard end to eye low down on stem that has end to tighten back on foredeck ....
Plans ... probably be fitted about 10 yrs from now !!
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Post by NigeL on Apr 27, 2007 18:16:13 GMT 1
I want a small bowsprit to push the foot of my cruising chute further forward so that it clears the furling gear (at the moment it catches on it when I try to gybe. Considering it only ever gets an occasional outing in very light winds, do you think I can use a piece of wood for this, or do you think I should get one done in stainless steel? Also how would you recommend attaching it? It could lie on the spare bow roller, but I haven't worked out how best to stop it lifting with the sail... Marc. Can you not tack CC to furling gear tack ? So that CC is same point as genny tack ? That way furling gear is then just ahead of CC as with genny ? I assume you are tack'ing the CC to stemhead fitting and that fouls the drum and gear that tries to sit slightly aft of the CC ?
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Post by malcb on Apr 28, 2007 6:44:59 GMT 1
Isn't there another way, that doesn't use a bow-sprit. If you run a tack line back to the cockpit, you could then slacken the tack a metre or so, to letting the tack of Cruising Chute blow forward and upward, thus giving some room for it to clear the forestay and furling gear. We used to play with an Assymetric Spinnaker like that on a J80, even though we had a retractable bow-sprit.
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Post by Barr Avel on Apr 30, 2007 14:20:32 GMT 1
Hmm, yes I hadn't thought of just giving some slack on the line which I use for the tack (the spin pole downhaul). Will give that a go and see how it all works.
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