Mainsail hoisting (low boom issues)

catlotion

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hi Everyone,

Please excuse the novice question, but we sometimes have issues when raising the mainsail on our Beneteau Oceanis 350. I'm not sure if we're doing something in the wrong order as the boom is often too low. We basically do the following:

  • Slacken mainsheet and kicker
  • Hoist main halyard
  • Ease off topping lift
  • Adjust mainsheet and kicker

The luff of the sail is raised correctly and tight but the boom sometimes doesn't seem to be high enough. We often sail with a single reef so was wondering whether it's to do with the clew end of the reef not being correctly adjusted? should this be really tight? (it is)

thanks,

Toby
 
Sounds like you are doing everything in the right order. The most obvious two possibilities are that you are not reefing correctly, or the sail is worn and has stretched out of shape.

Do you have single line reefing? I assume so for a boat of that type. I certainly find that we can end up with the boom drooping into the cockpit if I'm lazy with the reefing. Both reefing lines need to be tight otherwise the sail will not be uniformly tensioned - though the times that I end up with a droopy boom are the times when the luff reefing line is tight and the leech is loose. What happens if you have no reef in? Is the boom at the right angle? If not, it would seem to indicate that your sail has stretched and cannot set the correct shape.
 
One other thing not already mentioned... Do you have aft mast rake, and if so is it too much? I had this very issue, but it went away with new mast which was installed upright not aft raked by 2 feet....
 
Boom too low

In the first instance of full mainsail, is the clew (outhaul eyelet) as close to the boom as possible. Often a strap of double sided velcro can be used to bring the boom right up to the clew eyelet.
Also affecting the height of the sail is the tack (front eyelet) if this is lashed down really close to the boom then sail can not be hoisted to full height. I hope you are not using the cunningham eye (the eyelet about 20 cms above the tack eyelet at the luff) pulled down to gooseneck or indeed pulled on too tight. This is only tensioned down when sail is fully stretched out with halyard. You could et some alleviation of the problem by fitting a shackle or lanyard to the tack eyelet to allow the tack to rise hence the whole sail and boom to rise. This is really only possible with loose footed main. ie the bottom of the sail does not have a bolt rope in a slot in the boom.
Some mainsails have a flattening reef eyelet about 15cms above the outhaul clew eyelet. This can be plled down and out to give a small reef which fklattens the sail more than reduce area. If your sail is stretched getting one fitted and using it in lieu of normal outhaul may solve your problem.

Now when reefed again the reef clew eyelet must be snug against the boom to hold the boom as high as possible. Allowing the tack eyelet to rise a bit from the boom will allow the halyard to be pulled up more so raising the boom.
But as said mast rake will also give low boom and could be reduced by shortening the forestay lengthening the backstay. A perfectly vertical mast is OK IMHO and may or may not change helm characteristics. Boats typically exhibit weather helm when hard pressed and previous owner may have added more mast rake to try to minimise this. IMHO not worth the cost in low boom.
good luck olewill
 
Are you cranking down on the kicker? You dont really need the kicker until you are broad reaching - its there to keep the boom down when the pull from the mainsheet is in the wrong direction.

Otherwise, the sail has stretched at the leach.
 
I had a similar problem which was partly solved by having the bolt rope re-sewn by a sail maker. It had shrunk and was not allowing a full hoist due to the age of the sail. Assuming that your mast is correctly raked, it might be a good idea to get your local sailmaker to have a look and advise.
 
I don't know the boat in question. Does it have a fixed gooseneck? I can't see the leech stretching causing it. The sail would have to stretch in it's middle as well..
Does the headboard reach the top of the mast?
I have had boats with shrunken bolt ropes though and that is the obvious drawback. A droopy boom.
If you can't lift your gooseneck to get the headboard to the top of the mast you are stuffed.
Bolt ropes can be loosened off or replaced. Not a big job.

Below my old sail with shrunken boltrope. You get "puckering" all the way up the luff)
New main without.

sailcomparison.jpg
 
I would have thought a Benetau would have had a rod kicker. Although not essential, a rod can be a useful reassurance against cracked heads or damaged sprayhoods. If your sail is still too long in the leech you will end up with too much twist in the main, as mine has to a small degree. I have overcome it by making a leach cunningham out of simple lashing.

A droopy boom was a common sight in the days of roller reefing but shouldn't happen with a slab unless it is cut very oddly.
 
Thanks for all the replies everyone! I'll have a fiddle with the reefing line at the weekend and see what I can do. It doesn't have a rod/strut kicker (it's a 1986 model). Would quite like one but imagine they're not cheap!
 
The sail would have to stretch in it's middle as well..
Does the headboard reach the top of the mast?

yeah, the headboard reaches the top and the luff is tight all the way up. Reckon it must be reefing related. Can't remember what it's like un-reefed as we normally leave it in so beers don't fall over... :p
 
If the problem is reefing related and you have single line reefing .The trouble may be that the luff has been let off to far .
The reefing line works back to front and effectively tensions the sail unequally to the line of the reef row.this means that the luff reef eye needs to be tight befor the clew reef.
Check that the new luff reef cringle is a little way off the goooseneck so that it can still reeve through and is not chocker block,and then take in the reef line,so that the clew becomes tight before the luff.then take up on main halyard ,ease topping lift and sheet it.
.Cindy
 
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