One mast or two ?

sarabande

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The insurance company says it's about time I renewed the standing rigging (agreed). I have a very heavy duty in-mast mainsail furling system, and a roller furler genoa as well.

I hanker for a sail reduction process that doesn't rely on gears and swivels hidden deep inside the mast, so....

Do I ditch the 18 yr old mast and furling system, and go for two masts (ketch rig) with "normal" slab reefing on the main, and a cutter rig for the foresails, or a newer version of the roller genoa. It looks as if the main and both genoas are in pretty reasonable shape, but reliability and resilience are significant drivers in my mind. (It would also be nice to reduce weight aloft a bit, and have the ability to raise and lower masts independent of shore-based facilities)

Present boat config is a long-keel, motor sailer; and future use is long-term cruising, inshore waters, European canals, with a bit of cross-chanel and round France to Spain possibly. Crew is decrepit desk-driver, assisted by inexperienced SWMBO.

The present system works OK, but I suspect is nearing the end of its reliable life, and I am prepared to make big changes to get the boat "right" for the next 10 years, with easy sail handling and safe mast and rigging as the priority. I am not expecting dramatic improvement tot he sailing quality, which is at best, described as "sedate" !
 
Yawl or ketch rig brilliant for running with main down, All gear up,makes boat point closer without much loss of speed. Mine is a conversion on Falmouth Gypsy have found when running. the mizzen can over power the rudder, so I always make sure its on the Starb`d tack for safety, There are firms that will given, the vessels details work out the exact position for the mizzen and approx sail area. Best of luck.
 
No brainer, I love my Pentland KETCH! Even with roller reefing jib, if over powered it can still be better to just drop the main.
Sailing into busy moorings (previous 35 year old engine was not too reliable) Drop main to reduce speed yet keep good control, further cut speed by part reefing roller jib, Mizzen is only about 70sq ft but its position aft gives it the leverage needed for steerage control.
Anyway, Ketch always looks better than a slopp (whoops, sloop). Mizzen as a steadying sail when motoring, much less drag & shake than with the main. Main is smaller due to sail area being distributed over two sails. Masts are smaller and less prone to damage as rigging is often just as strong but under less strain.

Only down side is 3 sails to set & furl & a bit more string & poles. As I said I love it!
 
I think that conversion to Ketch or Yawl would require major changes to mast location especially in the support area and chain plate moving.
I would suggest evolution rather than dramatic change will be more successfull.
I can't imaginne having in mast furling but then again many people like it. It would seem a pity to throw away a sytem which may simply be in need of a little attention. The alternative is slab reefing which is very successfull but also requires flaking the sail onto the boom when stowing which requires lazy jacks etc and possibly 2 people.

As for the roller jib well once again I would never have it but so many people love it for cruising. The alternative may be a cutter rig with 2 smaller jibs each one of which can be removed or furled. If you don't have roller furling again you are up for a trip to the foredeck.

As for mast lowering. I live in a location where many people have to lower masts to exit to the ocean under bridges. One acquaintance does so on almost every sailling outing single handed on a 40 ft sloop rig.

Mast lowering is done on some truly large (25 metre) masts while under way quite successfully. Just do search you can get some ideas. The primary requirement is either a mast hinge or hinging mast step. I would reccomend this modification. good luck olewill
 
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Do I ditch the 18 yr old mast and furling system, and go for two masts (ketch rig)...reliability and resilience are significant drivers in my mind.

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Twice as many masts is twice as many things to go wrong. Putting the same amount of money and effort into two sets of rigging can only give you half the effort expended on each set, draw the obvious conclusion. A ketch will never point so well as a cutter. Read about "White Squall", which was converted by its famous owner from one mast to two. He always regretted it. The placing of the masts on a single-masted vessel is very different from the placing of the mast on a two-masted vessel, so you'd likely need to modify the hull to provide the necessary strength. A long sail plan suits a long keel better than fin & skeg. What's your sail area? How long is the boat? What construction?

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It would also be nice to reduce weight aloft a bit, and have the ability to raise and lower masts independent of shore-based facilities

[/ QUOTE ]I know a guy who took the mast of a 42ft cat down and put it back up while in the middle of a single-handed transatlantic race, so it's got to be possible. /forums/images/graemlins/smile.gif But a deck stepped mast will only ever be half as strong as a keel-stepped mast of the same scantlings because of the support afforded by the deck to the keel-stepped mast, so your requirements conflict with each other. Being a sailor that won't surprise you.

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future use is long-term cruising...

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One thing to think about is the downdraught from the mizzen. I've heard this can be very annoying on longer passages.

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...European canals, with a bit of cross-chanel and round France to Spain possibly.

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Obviously you won't go through the canals with the mast up. Although I wouldn't dream of doing the canals personally, if I were doing it I'd probably leave the mast at a port in England and motor to France, then go back for it later. Speaking from experience, a mast strapped down on the deck is a pain in the butt, even if it's on purpose made supports and as far out of the way as you thought it could be.

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Crew is decrepit desk-driver, assisted by inexperienced SWMBO.

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Think long and hard about Biscay. If your SWMBO has little experience, do you know for sure that your relationship will survive this escapade?

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I am prepared to make big changes to get the boat "right" for the next 10 years

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Consider changing the boat. It would be a lot easier than changing the sail plan.
 
wow, food for thought, thanks.

No wish to change the boat, because she has the needed compromise of excellent sea keeping, below decks space, and heavy construction. It seems that if I am going to have to spend £1k on rigging renewal, it would be a useful turning point to move to a new main mast, and put in a mizzen (the support structures are already there, and sister boats in the class have got ketch rigs).

The boat is 36ft loa, very full hull shape (15 tons displacement !), and long keel, so adding additional skeg area is not an option to adjust the centre of lateral resistance. The present main mast is 36 ft long, and is deck stepped. I want to be able to put in a more serious tabernacle, so that I can swing the mast down with an A frame, then strap both masts down on the wheelhouse top, so that nothing protrudes over the bow or stern.

I am not sure I agree with "two masts = twice the trouble" though !. The reductions in weight, pitching moment, and individual sail area, would seem to argue for less potential for breakage and more facility in handling the rig and sails, possibly ?

I guess I'll hand the boat drawings to the mast makers at LIBS, and see what they recommend. I 'm happy with the concept of a ketch rig, and did quite a bit of two masted sailing with the services, and old-style ocean racing, some time ago. Seems like a good opportunity to make the change, as a strategic decision for the next few years.

And, yes, your concern about short-crewing Biscay is noted !

/forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

thanks everone !
 
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I am not sure I agree with "two masts = twice the trouble"...

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That's not quite what I wrote. /forums/images/graemlins/smile.gif

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The reductions in weight, pitching moment, and individual sail area, would seem to argue for less potential for breakage and more facility in handling the rig and sails, possibly ?

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Er, possibly. /forums/images/graemlins/smile.gif

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I guess I'll hand the boat drawings to the mast makers at LIBS, and see what they recommend.

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Good idea. Let us know what they say?

My feeling is that 36 feet is rather small for a ketch.
 
I had a ketch for a few years, took her down to the Med, then Canaries and instead of going on across went back to the UK sold her and got a sloop... she was 40ft LOA... and indeed sometimes the mizzen could overpower the helm - always when its busy!! Quite exciting in the gusts!

Frankly at that length the only thing the mizzen mast is good for is hanging things on it - radar, wind generator etc... It really does double the work - hoisting two sails - and getting them set, stowing the sails and two sail covers all a pain... Also not as fast as a sloop of the same LOA and type... Sure you can drop the main when it blows up a bit and just use the head-sail and mizzen and a reefed down mizzen on anchorage is good for stopping rolling and keeping head to wind... I cannot tell you how much I do not want a ketch again unless I get something nearer 50ft when the weight of hoisting the main could begin to be a problem and breaking the main sail area down into smaller parts makes sense...

I love slab reefing - it seems safe, reliable and keeps the sail in good shape. I had bullet proof sails made in the Caribbean for my 36ft sloop and at the end of a circumnavigation they were as good as new and quite a lot of reefs had been thrown in and out of them. When a big squall comes along you really only want to be worrying about one fixed sail I think. ~

Michael
 
But a deck stepped mast will only ever be half as strong as a keel-stepped mast of the same scantlings because of the support afforded by the deck to the keel-stepped mast, so your requirements conflict with each other.
I would strongly dissagree about the deck stepped mast being half as strong as a keel stepped mast. Assuming decent mast support structure.... The mast is shorter so naturally stronger.Although if the mast is solidly chocked at the deck there is no difference.
A mast will tend to break in the middle of an unsupported section either through failure of support or from inadequate support in the design the bottom end does not contribute to the strength. IMHO.

Some masts are designed to be bent and this design can include the section from the keel to the top so a chocked mast at the cabin is wrong and the mast needs to be able to move within the deck hole.
To this end a lot of keel stepped masts around here have a hinge fitted into the mast about 1 metre above the deck. (including my friend's 20 metre mast.) this means that when the bolts of the hinge are clamped together the masty has original flexibility and strength.
The hinge here is a cut at 45degrees with flat plates welded on both faces. The front 2 edges are fashioned to fit a pivot axle while the back edge has 2 bolts to clamp plates together when up.

So no a deck stepped mast is just as strong if not more so than a keel stepped mast. olewill
 
Wiilliam_H
I haven't come across that bit of mast design before. (Hinged piece). Any chance of a photo to satisfy the curiosity please ?

thanks for the other comments - I am definitely going to stick to the present deck-stepped format, but with a decent tabernacle.

Michael E
thanks. Mainsail slab reefing, properly done (grin) , seems to be more resilient than any form of roller reefing, and you can have access to the sail for ease of removal / substitution of storm sail, etc. Though I have a gantry over the stern for radar and VHF aerials, I'd like to get the radar higher than its current 12 ft above the waterline.

I'll see what the mast experts say, then get back in due course.

ta v much all, and happy sailing in 2007.

S.
 
It needs to be a ketch.

A big heavy boat needs lots of sail - If its all on one mast theres too much heeling moment as well as being too much to handle in one lump.

Fit a mizen.
 
I bow to your direct experience of the breed ! /forums/images/graemlins/grin.gif

Should we start a thread on modern gaff rig ?
 
We can if you like

But there isn't much modern about my gaff rig, and despite having had the boat since last July I've not had the chance to sail her yet.

But seriously something like the Watson does need ketch rig.

Advantage of sloop - longer luff - better to windward doesn't mean much to us - whatever the rig your not going to go to windward worth bothering about

For us to go to weather we need full mizzen and reefed Perkins, or maybe vice versa.

To get the necessary area to drive a CW would mean a very high rig which would create a considerable heeling moment. Not what want in a boat like a CW.
 
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