Booms for single line reefing ?

B

Boo2

Well-Known Member
Joined
13 Jan 2010
Messages
8,603
Visit site
Hi,

My rigger has told me I will need a new boom in order to fit single line reefing because there is not room inside the one I have to fit the balance blocks etc. I know of booms from Selden (page 80) and Z-Spars that support SLR but these only permit 2 reefs to be run and I want 3 reefs as well as an outhaul and a flattener.

Note: I can't use 2-ine reefing because I cannot get enough rope clutches between the hatch and cabin side to cope with the extra lines.

Does anyone know of any other SLR fitted booms apart from the Selden and Z-Spars ones ? Ideally I'd like them anodised black to suit the existing spars.

Boat is a UFO 34, mainsail foot is 3.4m long.

Many thanks,

Boo2
 
Last edited:
Single Line reefing

far better to go for 2 line reefing and keep the existing boom. Sure there will be a extra ropes floating around 2 for each reef but far easier and more effective. If you must go SLR you don't need a balance block. Good luck olewill
 
I've converted 2 booms to single line reefing but only been able to do it for the first 2 reefs, the boom not being long enough for the third, which has in most cases has to be 2 line. The 2 line reef is actually quicker to use and tighter than the single line one.

Depends on how deep your third reef is. One end of the clew line is tied off on the boom outer end, goes inside the boom round the block then round the boom end sheeve, up to the sail reefing point and then down again to be tied off on the boom. The length of that clue line is longer than the boom so it can't be tightened. More blocks could be put in the boom to solve the problem but would generate too much friction, even if space allows.
 
Single line reefing is only possible for 2 reefs with the third a standard reef. The Z spar system uses floating back to back blocks. Sailspar I think would be able to quote for a black anodized boom, I think they also use the Z Spar boom sections.
One thing when changing the boom is to check the gooseneck will work, this can be another extra cost! The Z Spar section is Z360 and will be cheaper then the Selden.
 
Thanks for all the replies.

You may have seen that I edited my post to say that I can't use 2-line reefing because I cannot get enough rope clutches between the hatch and cabin side for the extra lines. Having read around I would have much preferred a 2 line reefing system but it can't be done so...

Are there really only 2 manufactureres of boom sections in the UK, Senden and Z-Spars ? Anyone know of any others that make internal SLR booms ?

Thanks again,

Boo2
 
I have seen balanced block single line reefing systems fitted to dinghies outside the boom. How important is it that they are inside the boom? People have lazy jacks with blocks, so why not reefing systems? :confused:
 
Boo2 said:
Thanks for all the replies.

You may have seen that I edited my post to say that I can't use 2-line reefing because I cannot get enough rope clutches between the hatch and cabin side for the extra lines. Having read around I would have much preferred a 2 line reefing system but it can't be done so...

Are there really only 2 manufactureres of boom sections in the UK, Senden and Z-Spars ? Anyone know of any others that make internal SLR booms ?

Thanks again,

Boo2
Click to expand...

Given that there is virtually no boat building industry left in UK it is not surprising there are few mast makers. The aftermarket demand for spars is tiny. Different 30 years ago when there were thousands of boats being built in the UK, each one having a mast and about half dozen suppliers.
 
Or, as an alternative </sudden thought> can anyone tell me who makes an aftermarket in-boom reefing boom suitable for a UFO 34 ? ISTM this would have substantial advantages over SLR in terms of line count anyway.

Thanks,

Boo2
 
Tranona said:
Given that there is virtually no boat building industry left in UK it is not surprising there are few mast makers. The aftermarket demand for spars is tiny. Different 30 years ago when there were thousands of boats being built in the UK, each one having a mast and about half dozen suppliers.
Click to expand...
Fair point, but I can obviously consider spar manufaturers from abroad as well, as long as they're reliable.

Boo2
 
Not sure why you can't have single line reefing with blocks outside the boom. In boom blocks only came in when single line reefing came into fashion. Many old booms have been converted to single line with external blocks. You have to be careful where you position them, but you can put the aft blocks on a track as in the Barton reefing kits. The only downside is a bit more string in the cockpit.

In boom reefing has a chequered history, although the newer ones are reported to be better. They are, however very expensive, particularly if you have to buy a new sail. They do have a good market in the new boat 50'+ performance cruising sector as the initial cost is similar to in mast furling.
 
I discovered that I could not use balance blocks due to one already in the boom for the outhaul.
My single line reefing system uses a SINGLE LINE and runs - from the boom through sail cringle - back to boom sheave - to mast end boom sheave - transfer block - sail cringle, and back to cockpit. Maybe there's a fair bit of friction (mainly where it is in contact with the sail) but I used ball-bearing blocks and IT WORKS. You don't need to replace your boom :)
BTW I've done it for all three reefs.
 
Boo2 said:
Thanks for all the replies.

You may have seen that I edited my post to say that I can't use 2-line reefing because I cannot get enough rope clutches between the hatch and cabin side for the extra lines. Having read around I would have much preferred a 2 line reefing system but it can't be done so...

Boo2
Click to expand...
Sorry I find that amazing that you can't have 2 line reefing because you don't have room for clutches.
The clutches could be stagered fore and aft or you could just use horn cleats on the bulkhead for the tack reef lines or cam cleats on top. These can usually be pulled down by hand the luff tension being taken up again by halyard.
I would urge OP to try 2 line reefing first or even although I don't like it the one line reefing as described with no blocks in the boom. olewill
 
I have single line reefing on my Hanse 311 which has a relatively large mainsail.
There are no blocks in the boom & frankly I would not want any. It. Works brilliantly
The line goes from a point on the boom just aft of the reef cringle, up to the cringle, back to the end of the boom, inside the boom & exit at the goosneck, up to a block on the luff cringle. Back down to a fairlead on the mast just above the gooseneck, down to the block on the mastbase then. Back to the cockpit.

My last boat ( a Stella) had a wooden boom. The system was the same except that the reef line ran down the outside of the boom. You could do this if your boom is not designed suitably. On my Stella the boom outhaul end had parts made by Barton. I am sure that if you really wanted to go down this route you could pop rivet the bits on to the boom. You could try this & see if you liked the idea first. It would be a cheaper way to experiment.
 
William_H said:
Sorry I find that amazing that you can't have 2 line reefing because you don't have room for clutches.
The clutches could be stagered fore and aft or you could just use horn cleats on the bulkhead for the tack reef lines or cam cleats on top. These can usually be pulled down by hand the luff tension being taken up again by halyard.
I would urge OP to try 2 line reefing first or even although I don't like it the one line reefing as described with no blocks in the boom.
Click to expand...
I've attached a pic below. To add extra clutches using the idea of staggering them fore and aft will mean moving all except one of them. Even so there is not enough room between their existing position and the front of the spraydeck to move them forward, and the angle to the winch won't work if I move them back.

I definitely want to be able to winch them because I will be on my own and may be knackered...

Thanks for the ideas though,

Boo2


clutches-layout.jpg
 
Boo2 said:
I've attached a pic below. To add extra clutches using the idea of staggering them fore and aft will mean moving all except one of them. Even so there is not enough room between their existing position and the front of the spraydeck to move them forward, and the angle to the winch won't work if I move them back.

I definitely want to be able to winch them because I will be on my own and may be knackered...

Thanks for the ideas though,

Boo2


clutches-layout.jpg
Click to expand...
Rutgerson clutches, 2x2 and 1x1 - if you change to a x4 clutch-block + 1 single you'll probably get them in. From memory the largest clutch block made by Rutgerson is a 4 block. I infinitely prefer ring clutches, such as Lewmar or Spinlock, but they are, I'm pretty sure wider.

My original 3 reef system has been easily converted to 4 lines, the 1st two of which are single-line. The 2nd one converted to single line runs in the old in-boom sheaves with additional external blocks. The additional friction of the inferior in-boom blocks makes the 2nd reef much more difficult to put in.
The big problems with single-line reefing lie in the frictional resistance and, by the time you've got to the 2nd reef, the vast amount of string in the cockpit.
I'd suggest you're stuck with single line, unless you can utilise the space on the starboard side of the main-hatch.
My foot-length is marginally under 4m and the main, being a 3/4 rig, rather larger than the UFO 31.
Personally I find, with a little careful adjustment of vang and mainsheet, when putting in the reef, no need for a balancing block.
As I sail single-handed and am definitely suffering the infirmities of age, single-sheet reefing is a boon, the 1st using all external Harken carbo-blocks goes in taking about about half a minute.
See the HarkenUS site for the detail. I've used it for about 8 seasons - 20k nautical miles on an oversize main which overlaps the backstay by about 500mm.
 
Last edited:
I find it strange that Selden are unable to supply you with a boom with internal single line reefing for three reefs, they certainly make them and my 33' boat is fitted with one. Perhaps it is because the UFO boom is quite short reducing the space for the cars to travel in.
However: the price is likely to be eye watering.
In five years I have never used the third reef and these days do not rig it, there are enough ropes flapping about with lazy jacks etc. I suspect my main is a lot bigger than yours too, though the reef intervals are much larger than I would like them to be. (I was told it had something to do with having a small enough third reef not to need a trysail, but it is far from efficient.) Offshore in heavy weather I would be much happier with a trysail.
There was a biggish ally boom lying abandoned under the hedge in the boatyard I used last winter, looked serviceable but I can not recall if it had two reefs or three, I think it may have been left over from a Westerly Typhoon that had a new rig a year or two ago, do you want me to enquire about it? you would probably have to shorten it quite a bit so there might not then be room for the third car anyway.
 
Hoolie said:
I discovered that I could not use balance blocks due to one already in the boom for the outhaul.
My single line reefing system uses a SINGLE LINE and runs - from the boom through sail cringle - back to boom sheave - to mast end boom sheave - transfer block - sail cringle, and back to cockpit. Maybe there's a fair bit of friction (mainly where it is in contact with the sail) but I used ball-bearing blocks and IT WORKS. You don't need to replace your boom :)
BTW I've done it for all three reefs.
Click to expand...

Same here: I have not taken off either boom end fitting on my 35 ft Jeanneau's SO35 boom to peer inside, but I have single line reefing and I am fairly sure there are no moving blocks inside the boom. There is a fair bit of friction, but with the reefing lines led back to the coachroof winch it works OK.

When I pull out the reefing lines from the boom to check or clean them - leaving a mousing line inside to reinstate, it really feels like I'm just pulling a straight line...
 
You must log in or register to reply here.

Share this page

Top