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  #1  
Old 05-11-2011, 12:25 PM
viking north viking north is offline
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Deck Level Main Boom Gooseneck Pros/cons ?

Cutting/shortening my overlength boom and the foot/leach of the main has been bugging the heck out of me, in that it could mess up the pocket on the main. While this is work that is 12months away it continues to eat at me in that, is there some way around it. the other day while working on the keel mold a light bulb flickered, why not mount the gooseneck down at deck level and have the boom slope upward as it runs aft. This would result in a shorter boom and foot /leach on the sail without disturbing the pocket too much.I did see this set up some years ago in one of the boating magazines. Other than some loss of visibility and the possibility of catching a boarding wave in the lower forward part of the sail, what other pros/cons would this set up present--Tnx. Geo.
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Old 05-11-2011, 12:39 PM
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Doug Lord Doug Lord is online now
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I've seen them on several boats-an IC and Hydroptere among them. Can't find a good enough picture but may be able to later. How big is your boat?

Heres one I had forgotten about:

click on image
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Deck Level Main Boom Gooseneck Pros/cons ?-lunne-201-sa-front-page.jpg  
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Old 05-11-2011, 01:01 PM
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Quote:
Originally Posted by viking north View Post
Cutting/shortening my overlength boom and the foot/leach of the main has been bugging the heck out of me, in that it could mess up the pocket on the main. While this is work that is 12months away it continues to eat at me in that, is there some way around it. the other day while working on the keel mold a light bulb flickered, why not mount the gooseneck down at deck level and have the boom slope upward as it runs aft. This would result in a shorter boom and foot /leach on the sail without disturbing the pocket too much.I did see this set up some years ago in one of the boating magazines. Other than some loss of visibility and the possibility of catching a boarding wave in the lower forward part of the sail, what other pros/cons would this set up present--Tnx. Geo.

Most Open 60 have exactly this arrangement.

Actual dimension along the boom will increase for the same width from the mast.
Boom kicker will have to be replaced with some ingenious system(s), which will (might) require attention each time you change tack.
Mast bending behavior will be different, as rather large boom pulling force, created with kicker, will be eliminated out of equation. In new design, this could allow a lighter section mast to be used.
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Old 05-11-2011, 01:02 PM
viking north viking north is offline
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Doug 30ft. mono hull full keel --build is posted under Boatbuilding--Building the Nancy G-----Geo.
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Old 05-11-2011, 01:15 PM
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Might be good.. got any sketches?
I've been pondering different setups too. Now I'm planning a boomles main, maybe even with luff set flying. A bit like lug..
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Old 05-11-2011, 01:25 PM
viking north viking north is offline
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Perm Stress -- The boom is now 17ft. the foot on the new sail i have (from a salvage job) is approx. 16ft. plus. I would like to get the boom length down to 14ft max. By installing the boom at an upward angle It would intersect the sails inward running leach(toward the mast)higher up, thus less length of boom would be required for this new foot on the sail. The main sheet tackle will be attached to the boom about 2/3 of the way out from the mast allowing me to attach the other end on a traveller along the top of the wheelhouse rather than cluttering up the cockpit . The wheelhouse roof /winshield will only be about 16in. max. above the base of the mast and because the upward angle of the boom there might be two benifits , less likely for a head strike, and the angular pull on the boom by the mainsheet gear might actually act like a mid boom downhall, especially as far as the sails leach is concerned. Am I thinking right here or is there something I have not fit into the equasion --Geo.
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Old 05-11-2011, 01:32 PM
viking north viking north is offline
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Teddy, I haven't doodled in any rigging yet on my sketch but i will do so today and post. My scaled drawing is just about complete and I should soon have my drawings and remaining specs from the designer, He was away on holidays but is now back in the saddle. Actually I have been slowing things down with research on the keel design but got it put to bed now. I certainly know more about full keel design than I did. __geo.
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Old 05-11-2011, 09:56 PM
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Quote:
Originally Posted by viking north View Post
Perm Stress -- The boom is now 17ft. the foot on the new sail i have (from a salvage job) is approx. 16ft. plus. I would like to get the boom length down to 14ft max. By installing the boom at an upward angle It would intersect the sails inward running leach(toward the mast)higher up, thus less length of boom would be required for this new foot on the sail. The main sheet tackle will be attached to the boom about 2/3 of the way out from the mast allowing me to attach the other end on a traveller along the top of the wheelhouse rather than cluttering up the cockpit . The wheelhouse roof /winshield will only be about 16in. max. above the base of the mast and because the upward angle of the boom there might be two benifits , less likely for a head strike, and the angular pull on the boom by the mainsheet gear might actually act like a mid boom downhall, especially as far as the sails leach is concerned. Am I thinking right here or is there something I have not fit into the equasion --Geo.
You will have to buy and install this long traveler.
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Old 05-11-2011, 10:34 PM
viking north viking north is offline
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Deck level gooseneck

Buy? This is something I try to avoid at all costs, barter or build is my style. Anyone can buy but then one misses out on the chase. Seriously what was my income generating woodworking, welding, quazi machine shop is now my hobby shop. Time for payback of all those years of shop buisness stress. The only downside, to get here, i've burnt up most of my lifes energy. Another possible problem with this set up might be, it will look down right ugly. Got too busy today getting the B&B ready for the coming season to do a drawing. I think it would look ok on a low superstructure but up and over a wheelhouse might just be too much. I'm into the old traditional look and i will at times suffer function for style. Regardless it might be interesting to see what evolves on the thread.--Geo.
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Old 05-12-2011, 07:36 AM
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You need to build a deck that can take the stresses of the gooseneck
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Old 05-12-2011, 07:59 AM
viking north viking north is offline
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Gonzo--I'd like to build a deck in my brain to take the stresses -- Have you looked into my build post lately-- I've got to shake my head sometimes and tell myself to get real with the framing. I'm fighting weight but that bartered african mahogony will be laminated and installed in her deck and cabin structure.
P.S. the weight of those stainless floor beam caps are included as internal ballast weight.
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