Reducing the foot of a sail

[JeremyF]

On the Bavaria 34 the boom is somewhat too low, by about 10 inches, to be safe in the event of a gybe. When I take the sails off for winter valetting at Lucas, can I get them to reduce the length of the leech, and trim the foot accordingly? Apart from loosing a few sq ft of main, are there any issues I should be aware of. I was planning to leave the reffing postions untouched.

<font color=blue>Jeremy Flynn/forums/images/icons/crazy.gif
Dawn Chorus</font color=blue>

 

[david_e]

is the boom socket adjustable at the mast? ie will it move up 10 inches. Are you sure about this modification? Still won't be 100% safe after it and then you might have lost it forever, so to speak.

 

[JeremyF]

Ive forgotten the names of the bits on the mainsail, so excuse me.
My plan was to leave the sail as is at the bottom of the luff, but shorten the leech by 10" or so, thus lifting up the boom.

Thats the theory...would it work in practice?

<font color=blue>Jeremy Flynn/forums/images/icons/crazy.gif
Dawn Chorus</font color=blue>

 

[Gunfleet]

You should talk to a sailmaker. They can do all sorts of things to a sail to keep as muchsail area as poss while changing the shape. I've just had a new sail made with a 'kick', which is to say that it clears the cockpit (no dangerous 'boom on nut' situations) but still sets properly and the gooseneck is in the right position on the mast.

 

[david_e]

Ducking and Gybing

They could recut the sail to almost any size and shape within reason and taking 10" from the bottom would need a new foot, clew etc and all the bits and bobs that rae at the bottom taking up and put back in 10" higher. It would proably be necessary to get the boom fixings changed first so that accurate measurements could be taken. Also make sure that you have enough extra line on mainsheets and reefing line (would have thought so but if there a few blocks it becomes 40" not 10 and so on) My concern would be changing such a fundamental thing as this could upset the balance of the boat and overall performance. Taking 10" from the bottom is not quite the same as reefing from the top down. The potential gain is minimal 'cause I know you don't race so can't imagine you are gybing that often, and what happens when you want a '38 or '40.

Learning to duck is cheaper and alot less hassle, then you could always get a crash hat!

 

[Guest]

It will almost certainly reduce the residual value of Dawn Chorus. It will cost you a lot more than you think. If you are worried about an accidental gybe far better to rig a preventer with a control from the cockpit. I will show what I used to do on my 336, a line and maybe two blocks will achieve the result.

cheers

Pete

 

[Guest]

It will probably be quite an expensive job. Rather than chopping off the foot. The top of the sail will be cut down and the leach reshaped. All the batten pockets and the reef patches will have to be redone.

One can't just lop off the bottom sections as that is where all the broadseam (built in shape) is. Sail would end up looking like a sheet of lino.

Suggest ducking, preventers and good mainsheet trimming as cheaper alternatives!

 

[Strathglass]

Jeremy
Why not get your sailmaker to fit a flatening reef eye to the leach of the sail about 12 inches above the clew. Then you rig a single reefing line from the boom through the new eye then back to a block on the boom near the original clew position on the boom. You can then lead this back to the cockpit.
To use it you just loosen off the main, loosen off the kicker, pull in the new control line then retention the main and the kicker.
The rear of the boom is now 12" higher and some power is removed from the main.
This is a very quick and easy way to reef but it also means that you still have the full sail area of the main available if and when required.
It is also a relatively simple modification for a sailmaker to add but he will also probably have to add some reinforcement
to the sail around the reefing position. He may sugest an alternative to an eye such as a strop or a block.
To cut the sail as you have sugested would be very expensive, would reduce the value of your yacht and may not suceed in giving you the desired result.
Iain

 

[AndrewB]

Interesting question!

There seems quite a bit of sense in this for cruising, though learning to duck gets pretty instinctive after a while.

However, it's almost universally the case in modern rigs that the boom is set at right angles to the mast. Even where the tack of the mainsail is not a right angle, a wishbone is likely to be used, as on a Freedom.

But is this a matter of necessity, avoiding sheering strains on the gooseneck; or simply one of fashion, perhaps because of a the way racing measurements are made?

You will of course raise the centre of effort of the sail and move it slightly forward. In terms of balance when heeled, these tend to cancel out. The sail would have less power, but still tend to tip the yacht as much, so would have to be reefed in the same strength of wind. But these differences would be too small to worry about for cruising. You would also need to change the reefing eyes on the sail slightly if you wanted the boom to be similarly cocked when reefed.

I can't see what you have to lose other than the cost of the job and a possible small resale value on the sail - plus the risk of looking a bit odd since we are so used to parallel booms. But before you go the whole hog, why not get a clew eye fitted about 10" up the leach, and see how that works? It would be most interesting to hear what your sailmaker thinks.

 

[JeremyF]

Good suggestion, Iain. I'll ask the sailmaker about that idea.

I think I'm reasonably confident about ducking. Its the family is a couple of years when they get above 5'8" or so.

Earlier ideas about preventers are very sound, but I'm not sure I want a preventer when in the busier parts of the Solent. Sometimes a gybe is what's needed, and I'd need to feel confident I could get rid of the preventer quickly before I rigged that up.

What triggered the thinking here were the flukey conditions Sunday morning. The wind was changing direction every few mins. We were close hauled, and I saw, coming the other way, a yacht gooseinging, with no sign of a preventer. On my head be it - I think not!

<font color=blue>Jeremy Flynn/forums/images/icons/crazy.gif
Dawn Chorus</font color=blue>

 

[halcyon]

May be dublicate post, but on our old Hurley 27 we needed to reduce leech to counter stretch over the years. Had 10 inches trimed of the top and new head board fitted, saves cutting the sail at the bottom.


Brian

 

[jimi]

Jeremy,
the height of the boom was a critical factor in my choice of boat, imposed by SWMBO! It perhaps ought to be given more consideration by those buying family boats.

Have you checked the measurements etc to see that the gooseneck is in fact at the correct height?

There may also be scope to raise it a little without altering the sail.

Jim

 

[bedouin]

I think the idea of a flattening reef is an excellent one - it's easy to install, would do what you require and give you more control of the shape of the sail in a variety of wind conditions.

I would also recommend a preventer, not only from the safety aspect but it also gives better control of the boom, particularly when running in light winds, allowing the boom to be set in position rather like a spinnaker pole. However the preventer must be lead back to the cockpit. In that case letting it off before a gybe takes a matter of seconds.

 

[tony_brighton]

Last time we ran all the way up the Solent we rigged a preventer each side led back to the cockpit. As we jibed, let one off and hardened up the other. We are giving serious consideration to buying a boom brake at the SBS just to make this even safer.

 

[Mirelle]

Go right ahead.

"Technically", the shape of the main will be adversely affected since the cloths will no longer be lying parallel to the boom.

The sailmaker may try to dissuade you because of this and may say that he will not be responsible for the results.

In practice, the difference will be so small that you will not notice it, and you certainly will not notice any difference in the boat's sailing ability. I would go ahead.

Working gaff cutters, and yachts with some workboat influence in them, always have the boom well angled up for two reasons - safety in gybing and avoiding the boom dragging in the water when rolling on a run. Extreme racers started to have booms parallel with the waterline and for some reason this habit stayed with bermudian boats so it "looks racy" to have the boom level with the waterline.

Frankly I think it is done because the drawing looks nice that way and you might sell another boat or two!

One wonders - how many people have died because of this silly practice?

 

[jimi]

What\'s a boom lock?

Never heard of them. How do they work?

Jim

 

[imptish]

Re: Go right ahead.

My understanding is that the cloth is laid perpendicular to the leech and not the boom.

I agree that a flattening reef would be the best solution.

My boat is a racer although hardly extreme and the boom is not parallel to the water, the clew is lower than the foot! The flattening reef brings the boom parallel to the water and subsequent reefs raise the boom further. Having the boom parallel or angled down slightly allows the kicking strap to have a more efficient downward force at the clew.

 

[Guest]

Re: What\'s a boom lock?

http://www.boomlock.com/prodcomps.htm

I looked at them once but decided preventers were a simpler solution for the odd times I needed it. I don't know how you rigged yours but on my last boat , line from outer end of boom forward on block and then back on another block to cleat by helm position.

Pete

 

[AndrewB]

Flattening reef??

The idea of an additional clew in the sail occurred to me, too. But I don't see how this alone will serve as a flattening reef, unless this is a shelf sail. More likely to make a conventionally cut sail a little fuller specially towards the luff, unless matched by an eye (Cunningham?) at the tack, which would defeat the original purpose.

 

[bedouin]

Re: Flattening reef??

I'm definitely not an expert on this - but you do get flattening reefs using that mechanism - and I thought they worked on conventionally cut mains.

Thinking about it, using an extra clew cringle will take fabric out of the leach, and also pulling the clew back may also take some fullness out of the body of the sail as well (because the cringle will be a little further away from the gooseneck with the reef in than without).

It might be fun to play around with the first reefing cringle some time to see if that can be used to control sail shape effectively.