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  #16  
Old 10-17-2009, 06:58 PM
Shack Shack is offline
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MikeJohns,
Thanks for your reply. I think that was most of what I was looking for. I have heard of criticism of bow sprits because of the way they might submerge.

Sounds like an appropriately constructed and stayed sprit shouldn't have major issues in shorter period, high waves. ...if not much more than a no-sprit equiped bow.

Thanks
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  #17  
Old 10-21-2009, 03:40 PM
Perm Stress Perm Stress is offline
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I could remember a couple of stories from close sailing buddies:

1) stainless pipe structure bowsprit, (~32ft boat) with anchor and additional forestay out on it, but walking platform itself made of wood, fastened with screws holding it from BELOW. Wood carried off by wave several times in several seasons of sailing the Baltic and North sea. As owner explained, this easily detachable design of platform was intentional. No damage to actual boat made.
2) Wooden platform bowsprit on 54ft boat, wood structural. Two anchors and main forestay out on it. A 3d successive wave carried it off when sailing out of Brest. Mast was saved from falling down, one anchor lost overboard, one retrieved. Deep scratches (some down to iron strengthening in ferrocement hull).

...
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  #18  
Old 10-21-2009, 07:50 PM
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BeauVrolyk BeauVrolyk is offline
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Bow Sprit Advantages

I would hold that there are a number of advantages to bow-sprits, but that modern boats probably don't need them, except down wind. Long long ago boats were quite heavy and had tremendous drag due to being slack bilged and long keeled. Given the drag, one needed a BIG sail plan to move the boat, so there was a bow sprit and a long over hanging boom. While these boats are beautiful to look at, they are a bear to sail, I've sailed them all my life having grown up on a gaff cutter which was guilty of all of the above.

If one does the obviously correct thing, from a design point of view, and makes the boat of modern materials and builds it light, then there's no need for the massive sail area of yore and the bowsprit and overhanging boom disappear. (Consider how small the sails are on a 20 or 30 square meter boat) The only reason that one has a bow sprit today is to allow you to set a great deal of sail area on a reach or run without the difficulty of a spinnaker pole. If you had a big crew and no racing rules to deal with, you'd obviously us a spinnaker pole rather than a sprit because it's better in every way - especially on a run. IMHO.

All of that said, a boat with a sprit looks lovely and the thing is really quite good to tie the anchor line to.

With regard to the water damaging the sprit, this shouldn't ever happen. The loads that are put on the sprit by the sails are tens of times larger than the load that could be put on it by the water. The forces on the jib stay could be well in excess of 70,000 pounds on a mid-sized boat, you'd have to be moving the sprit through the water pretty darned fast to come close to that load. So, I'd suggest that you not worry about it.

I would strongly suggest that you think hard about a lighter boat if you think you actually need a sprit, unless you a nostalgic old fart like me who just likes the way they look.
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  #19  
Old 10-21-2009, 09:51 PM
ancient kayaker ancient kayaker is offline
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A bowsprit gets my vote any day for appearance. I wonder if I can put one on my 3m boat.
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  #20  
Old 10-22-2009, 04:42 AM
capt vimes capt vimes is online now
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Quote:
Originally Posted by gonzo View Post
Bowsprits have their own stay. There is a forestay attached to the bowstem or close to it
please read perm stress' post....
i understand that this ship attached on the last page has a cutter-rig but the MAIN forestay is mounted to the bow-sprit... this forestay is taking the main load - as i understand - and i do not think that this is a good idea because of incidents like the one perm pointed out...
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  #21  
Old 10-23-2009, 12:20 AM
MikeJohns MikeJohns is online now
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Quote:
Originally Posted by capt vimes View Post
please read perm stress' post....
i understand that this ship attached on the last page has a cutter-rig but the MAIN forestay is mounted to the bow-sprit... this forestay is taking the main load - as i understand - and i do not think that this is a good idea because of incidents like the one perm pointed out...
You can have a varity of combinations of forestays and most bowsprit designs will often have an inner stay or two, and will usually require this for a storm jib.

Appendages like keels rudders and bowsprits do fall off at times but look to the design if you want them to remain attached, you will allaways find incidents of failure for anything,

some older working boats had sprits that were run out with a tackle once at sea With the line with one turn around a post these bowsprits could be used to ram the dock wall at low speed to stop the vessel and they withstood even that treatment
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  #22  
Old 10-23-2009, 01:27 AM
ancient kayaker ancient kayaker is offline
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Quote:
Originally Posted by MikeJohns View Post
... some older working boats had sprits that were run out with a tackle once at sea With the line with one turn around a post these bowsprits could be used to ram the dock wall at low speed to stop the vessel and they withstood even that treatment
Would that work when some seadoo is approaching on a collision course at full speed while the driver is chatting over his shoulder with his girlfriend? Would anyone be offended if it were sharpened?
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  #23  
Old 10-23-2009, 03:29 AM
capt vimes capt vimes is online now
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Quote:
Originally Posted by MikeJohns View Post
some older working boats had sprits that were run out with a tackle once at sea With the line with one turn around a post these bowsprits could be used to ram the dock wall at low speed to stop the vessel and they withstood even that treatment
oh - i know that but...
this is the 21st century and bowsprits in modern shipbuilding are imo just there to sail a gennaker, spi, blister etc from them and to keep the anchor away from the hull if you are not able or willing to store it in its compartement...
and therefore i think that a bowsprit should never be part or take anything from the rig.... it has become nothing but an appendage and if it falls off... no harm done - eh?

nobody is using a bowsprit nowadays as a ram... or have it as an integral part of the sailplan and rig... there is no reason for doing so.

but i must confess that my focus is solemnly on sailyachts used for recreational purposes and cruising... racing is something different still and workboats i have no clue about whatsoever....
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  #24  
Old 11-01-2009, 01:33 PM
Milan Milan is offline
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Quote:
Originally Posted by BeauVrolyk View Post
… Long ago boats were quite heavy and had tremendous drag …. needed a BIG sail plan … gaff cutter … beautiful to look at, they are a bear to sail ,,,

the boat of modern materials … light … no need for the massive sail area …
All of that said, a boat with a sprit looks lovely and the thing is really quite good to tie the anchor line to.

… nostalgic … just likes the way they look.
It isn't oftenly done, but combining modern light materials and ancient sail plane can produce very interesting boat.

I think that you could possibly like this high performance gaff cutter:
http://www.balta.fr/etoilehori2.html
Attached Thumbnails
bow-sprit-high-seas-pourreykjavik.jpg  bow-sprit-high-seas-demicoque.jpg  
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  #25  
Old 11-01-2009, 02:05 PM
ancient kayaker ancient kayaker is offline
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It's beautiful! Except for the house on the deck that is - looks like a container vessel. That hull shape doesn't look all that ancient though.
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  #26  
Old 11-01-2009, 04:57 PM
Milan Milan is offline
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Quote:
Originally Posted by ancient kayaker View Post
… house on the deck …
Dog house can be easily omitted, as on this one:

http://www.balta.fr/chiloe.html

However, that could mean quite limited headroom bellow, as she is shallow under water line and has a low freeboard.

Quote:
Originally Posted by ancient kayaker View Post
… That hull shape doesn't look all that ancient though.
No, hull shape is not ancient at all. That’s why she is a rocket.

She certainly rises quite a few eye-brows, when she sails circles around modern and fast looking boats. I think that many sailors who automatically dismiss gaff rig as slow, would think twice if they see this boat in action.

Etiole Horizon's bowsprit:
Attached Thumbnails
bow-sprit-high-seas-imag0062.jpg  
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  #27  
Old 11-01-2009, 05:50 PM
DGreenwood DGreenwood is offline
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Quote:
Originally Posted by ancient kayaker View Post
It's beautiful! Except for the house on the deck that is - looks like a container vessel. That hull shape doesn't look all that ancient though.
I think you might be confusing Life Line Banners with a deck house. Enlarge the pic and look closer.


Fun boat!
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  #28  
Old 11-02-2009, 06:15 AM
MikeJohns MikeJohns is online now
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Quote:
Originally Posted by Milan View Post
...........
She certainly rises quite a few eye-brows, when she sails circles around modern and fast looking boats. I think that quite a few sailors who automatically dismiss gaff rig as slow, would think twice if they see this boat in action.
Interesting but if you couldn't fly the topsail to windward the lift-drag ratio would be poor, always the achiles heel of the gaff rig is the short luff on the mainsail for windward work.

If yo know the vessel and the designer I'd be very interested to know if they produced any polars.


cheers
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  #29  
Old 11-02-2009, 02:40 PM
Paul B Paul B is offline
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Quote:
Originally Posted by Milan View Post
That’s why she is a rocket.

She certainly rises quite a few eye-brows, when she sails circles around modern and fast looking boats.
Can you give us details of these feats of speed?

When this boat did the Route du Rhum 2002 it was outclassed, terribly slow compared to the rest of the 50 footers. I believe it was sitting in last place, more than 1200 miles behind, when the first boat in class finished. It was more than 600 miles behind the next to last boat, IIRC.
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  #30  
Old 11-03-2009, 01:24 PM
Milan Milan is offline
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Quote:
Originally Posted by MikeJohns View Post
Interesting but if you couldn't fly the topsail to windward the lift-drag ratio would be poor, always the achiles heel of the gaff rig is the short luff on the mainsail for windward work….
Yes, short luff is gaff’s weakness , but this boat is stiff, she can fly top sail most of the time, and it seems that sails have a very good shape, including the top sail. No buggy, sagging sails one usually expects from the gaffer. So, she is able to sail very well to the windward, pointing a little lower then she would with highly roached bermudian sail plan, but still doing very fine.

Quote:
Originally Posted by MikeJohns View Post
… If you know the vessel and the designer I'd be very interested to know if they produced any polars.
cheers
I don’t know designer personally and I couldn’t find any polars, unfortunately. Designer claims that her best speeds are about 11 knots to windward and around 15 reaching.

Quote:
Originally Posted by Paul B View Post
Can you give us details of these feats of speed?
When this boat did the Route du Rhum 2002 it was outclassed, terribly slow compared to the rest of the 50 footers. I believe it was sitting in last place, more than 1200 miles behind, when the first boat in class finished. It was more than 600 miles behind the next to last boat, IIRC.
Actually, in 2002 Adecco Etoile Horizon lost time because she, (solo skipper Bob Escoffier), diverted from the race course to rescue Karine Fauconnier from her heavily damaged trimaran nearby Madeira.

But that isn’t really relevant to this thread. I wasn’t talking about racing. At the time of Route du Rhum she was stripped out racer, with 8.5 tons displacement, Bermudian rig, and considerably deeper fin.
With her wooden strip planked hull and aluminum mast she is not competitive racer against new generation open class boats.

She is transformed in the fast cruiser. With cruising accommodation she is about two tons heavier, has a shallower bulb fin, but still, a very fast boat. Can you imagine surprised faces on the modern looking boats when they see gaff cutter sailing at 15 knots? Looks like a lot of fun.

This is how Adecco Etoile Horizon looked during her racing days:
Attached Thumbnails
bow-sprit-high-seas-horizon1_524x664.jpg  bow-sprit-high-seas-horizon3_760x373.jpg  bow-sprit-high-seas-adecco2.jpg  

bow-sprit-high-seas-adecco4.jpg  

Last edited by Milan : 11-05-2009 at 06:23 PM.
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