Expected forces on reefing lines ?

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Boo2

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Hi,

I've given up on single line reefing for the mainsail of my UFO 34 and am trying to find ways of getting in 6 off rope clutches each side of the coachroof so I can fit twin line reefing instead. By twin line I mean one line at the luff of the main and another separate line at the leech.

The problem I have is there's not very much room between the grab rail and the side of the main hatch so I need the smaller design of clutch like the Lewmar D1 or Bartons 550. From reading around I understand the Lewmar is preferable over the Bartons but first I need to know what the holding force I need in a clutch for twin line reefing ? Both the types I'm considering have holding forces around 500kg which is around half what the bigger clutches can handle.

Any advice gratefully received,

Boo2
 
I am not answering your question mainly because I have difficulty in identifying the advantage of encumbering your boat with so many lines. I manage to reef from the mast with the halyard, rams-horns, and pennants all close at hand with very few problems* (as long as I remember to release the vang before leaving the cockpit). Having the main halyard at the mast makes lowering the sail easy - particularly when picking up a mooring single-handed.

*Having just had a very enjoyable Xmas with my much loved children I have been left in no illusions that a 66 year old with dodgy knees and spine is not as agile as I was. Even so the simplicity of mast reefing remains my preferred option.
 
I would suggest that the tension can be estimated from the leach and foot tension in the main.
Do you have a 6:1 mainsheet on the boat?
Would you say the force to sheet in hard when it's blowing is of the order of 100lb?
I reckon 500lb of leach tension and 200lb of foot tension might be roughly right.
The reef lines are going to see similar loads. The ratio will depend on the geometry at the clew.
The tack lines are more lightly loaded but still significant.
Don't know if that helps or not.
The Harken website used to be helpful for this sort of thing.
 
Reefing lines

As said the load on the clew reefing line is essentially equal to the mainsheet load (allowing for difference of position of mainsheet attachment to clew). in any case quite a lot with a huge concern about chafing at the sail clew eyelet.
Regarding clutches. I think these are very much over rated as useful. I went for additional small winches on cabin top for reefing lines. The lines not used need only be tidied while the lines used go around a winch then to a horn cleat or similar fool proof cleat.
The only clutch I have on my boat for the main halyard slips over time so I end up wrapping the halyard around a horn cleat anyway. Plus of course a clutch can be more expensive than a small winch.
Anyway good luck olewill
 
We have rams horns with spectacles and the 3 reefing lines led back to clutches under the sprayhood. Average time out of the cockpit to reef is under a minute. To me this is the ideal compromise.

- W
 
Staggered

Boo2 said:
Hi,

I've given up on single line reefing for the mainsail of my UFO 34 and am trying to find ways of getting in 6 off rope clutches each side of the coachroof so I can fit twin line reefing instead. By twin line I mean one line at the luff of the main and another separate line at the leech.

The problem I have is there's not very much room between the grab rail and the side of the main hatch so I need the smaller design of clutch like the Lewmar D1 or Bartons 550. From reading around I understand the Lewmar is preferable over the Bartons but first I need to know what the holding force I need in a clutch for twin line reefing ? Both the types I'm considering have holding forces around 500kg which is around half what the bigger clutches can handle.

Any advice gratefully received,


Boo2
Click to expand...
Is it possible to set one set of clutches behind another with the lines going around or between the forward set to the second rank? Perhaps single clutches alternating so you can use the larger size would work.
As to loads, I reckon our max mainsheet pull on a 33' boat with a 32 M2 main is probably 75 kg times a six part sheet is 300kg, but could it be 100kg times six? sorry not helpful.
Second thoughts, the reef line is two part at the clew so loads almost halved
 
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Sounds like a lot of ropes to have lying around. I have found just using single lines back to the cockpit to control the leech best. I have to go to the mast anyway to open/close the mast gate to allow the mainsail slugs to drop or feed back in so putting the luff reef point onto the ramshorns can be done at the same time. It takes about a minute or so as I don't need to get the tensions all correct. I do lead the main halyard back as well so the tightness of the uphaul and leech tension can be adjusted from the cockpit and also means another crew member can assist remotely during reefing.
 
webcraft said:
We have rams horns with spectacles and the 3 reefing lines led back to clutches under the sprayhood. Average time out of the cockpit to reef is under a minute. To me this is the ideal compromise.

- W
Click to expand...

Thats what I have and to be honest, I would rather have the whole lot at the mast. Halyard and reefing lines the lot..

Solo I can balance the boat so I can get up and reef and back in 2 or 3 minutes..

As it stands I have a fender cleat on standby by the mast so when I hook the eye on the rams horn I can pull the halyard up that bit... Then go back and hope it has not fallen of yet :(

To finish from inside the cockpit.

If it where all at the mast, it would be easy and less ropes in the cockpit...
 
Thanks to all for the replies, but I should say that I am not considering doing the reefing at the mast. There are several reasons for this but I would prefer it to be taken as a given, thanks. Btw, the number of lines being brought back to the cockpit is only going to increase by 2 from 10 to 12 so I don't think there is any issue with that, plenty of boats have more lines. Also, thanks johnphilip for the idea, but the space is constrained by the sprayhood fore and aft so I cannot offset the clutches.

I really just need to know whether the tension in reefing lines is likely low enough to be handled by the smaller versions of rope clutches ? Thanks to those who have posted finger-in-the-air estimates for that, I have also asked Lewmar their opinion, but obviously they will be shut until the middle of next week, and then there may ba a backlog before they get to my question...

Thanks again for all the replies,

Boo2
 
On my Westerly 33 I have 3 reefs and 6 ropes led back to cockpit. The clutches are quite small but have never caused a problem. My lukk lines go from the horns up through the gringles and back down to the turning blocks, this should almost halve the pressure.
Someone above mentioned using a winch for the lines. I caused myself problems doing just that. I pulled down on the reefing line too hard and damaged one of the cars at the end of my full length battens.
Allan
 
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I inherited a partially led-back setup, which I have changed to all led-back. Although tbh if the boat had everything at the mast, I would have left it like that. But putting some of your lines at the mast and some at the cockpit is a lot of hassle, IMO.

I used very cheap little Barton clutches for the tack lines. You could probably just use horn cleats for these. They do not need to be tensioned as such, you are simply holding the tack down and then winching the halyard back up again.

The clew lines are on Lewmar D2 clutches, they are probably way oversized for the boat, but they were already fitted.

The halyard does not really need a clutch as it is the last thing to be winched.

To save clutter I don't have the third reef reeved. If I think I will need it, I can swap the first reef's lines over. I've only set it a couple of times though.
 
Should of added I just upped the size of my reefing lines from 10mm to 12mm when I replaced them (35' old 3/4 tonner).

The old ones had really started creaking under load... Is that any help?
 
I do understand the OP's concern about the frictional resistance of single-line reefing, but think his solution is regressive.
Rather than try and have two separate lines for each reef (for which he clearly has insufficient room for the necessary clutches) he would do far better to either:-

1. Revert to conventional jiffy reefing with rams' horns on the gooseneck (OK lead the tails back to the cockpit. OR
2. Put in some decent pulleys to reduce the frictional resistance on his current single line set-up.
My boat has a larger main than the UFO 34 and the first two reefs are single-line and perfectly usable by a physically challenged 76 year old.

As already suggested the Barton website has some reasonable suggestions for practical single-line systems - but using high-quality ball-bearing pulleys rather than the ones he has found unsatisfactory on his current set-up.
 
I am delighted that the OP is going for two and not singleline reefing

Having gone the exact same route albeit at a tad larger size, may I recommend the addition of a self tailing winch or two and certainly a boom strut as real, helpful, hands free aids?
And as mentioned, lead the luff lines up from the tack cringle to and through the reef cringles and back down to give 2;1 reduction.

I and many others don't actually keep the 3rd reef fully rigged until the first and second are in use and weather deterioration seriouslty anticipated. Which further simplifies the layout and the ££ a lot! And is less faff when hoisting and lowering, a lot less faff.

There's quite a bit going on at the cockpit,rope wise, what with staysail halliard, pole, spinnaker, lazyjacks and inhauls to stow the lazyjacks too when hoisting the main in a sloppy sea...nevertheless with 5 clutches per side, two self tail16s and a dogcleat there are effectively more clutches than I actually use.
6 would be a lot even for a dedicated singlehander cruiser possibly?

The OP may wish to shorten the cabintop handles, raise the clutches on angled wooden bases, stagger them fore and aft or even mix n match with some cleats on the top or bulkhead too, and make allowance to get a good swing on the winch handles under the dodger too.

Why not contact other UFO owners who have sweated all of this correctly already? The trick is to get all the kit in exactly the right place and alignment both horizontal and vertical and with respect, it is a bit of a subtle learning curve that belies the long series of questions coming from the OP.

There must be dozens of sorted UFOs with good internet access and photos, and DIY owners happy to help specifically.

Btw in operation....When reefing I only actually need to use a winch for the last bit of the leachline, the rest is done easily by letting the sheet out, halyard off, the sail feathers in the breeze, the strut supports the boom, the two-to-one gets the luff down and cunningly one has released 'just enough' main halyard anyway to the magic marker ring on the rope tail so that it doesn't need retensioning automatically..

All very longwinded to write :)
 
Boo2 said:
........ find ways of getting in 6 off rope clutches each side of the coachroof so I can fit twin line reefing instead. .......... Any advice gratefully received .....
Click to expand...

On a yacht your size you don't need clutches for the tack pendants, so thats 3 down straight away. The number 1 reefing pendant can be used as the number 3 reef, so thats another down; just 2 clutches now.

Obviously you need to secure the tack pendant but a row of 3 cleats, staggered, would take up much less room as well.
 
I used to race on a dayboat that reefed.
We didn't have clutches, but the first reef was rigged 2:1 along the boom to a stout cleat.
Maybe a tackle could be shifted to the reef in use or something?
After all only 2 of these lines are doing much at any one time.
With tackles on reef lines and halyard we could have reefs in and out in seconds.
 
.
If you have a third reef then I would recommend having it reeved and ready for use. The last time to be faffing about rigging the third reef using the first reefing line is when you suddenly realise you need it. Sods law says the first reef will somehow be jammed in the (twice-reefed) sail and getting high enough to catch the flogging leech and thread it in what are by now pretty rotten sea conditions is likely to be fraught.

All IMO, but based on experience.

- W
 
webcraft said:
.
If you have a third reef then I would recommend having it reeved and ready for use ..... getting high enough to catch the flogging leech and thread it .....
Click to expand...

You don't need to try and catch anything or work on a flogging sail. Once the second reef is in you undo the first and tie it to the messenger, then pull it through the 3rd reef cringle and make off around the boom.

It should be a very easy manoeuvre standing beside the boom with no effort, based on my experience (you do need to be sailing a fine reach or higher - which is why its done just after the second reef is put in). However, if you have the space for the 3rd reef it is better to have it rigged as you suggest.

The issue the OP might have is that he has 2 reefs, an out haul and a flattener, hence doesn't have the space for a 3rd reef sheave.
 
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