Not so single line reefing

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jonjo

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I had a chat yesterday with my local rigging shop about fitting single line reefing. The following Sparcraft diagram gave me an impression that the upgrade would involve just one detour for the leach reefing pennant up to the luff cringle.

http://www.sparcraft.com/uk/products/booms/single_line_reefing_syste.asp

The local rigger strongly suggested an alternative design as illustrated at the following Z Spars page. Apparently this far more complex setup is the Rolls Royce of single line reefing.

http://www.zsparsuk.com/slrboom.htm

Does anyone have hands-on experience of these rival designs used with a large mainsail?
 
I have the first set up and it works very well. The main features to make it work efficiently and with minimum sweat are making sure you have large enough pully wheels on the leech of the main and also using a fairly slender non stretch rope- I have dyneema. There are so many angles involved that you have to make big efforts to reduce the friction.

I now swear by this system, especially when sailing short or single handed.

Regards

Alex
 
I too have had the first set up on last two boats worked fine only thing I did to make it easier was to mark the main halyard so I knew how far to lower the main that way I protected the block attached to the sail.

I have had experience of the second solution where it jambed and there was nothing we could do to correct it without removing end of boom. Not something you cannot really do at sea.
 
Over the years I have played with single line reefing,I have come to the conclusion that it should be rigged with all lines,turning blocks and pulleys etc outside the boom,ie where you can see them and maintain them easily.
Putting complicated blocks and leads inside the boom is IMO a recipe for disaster cos if it goes wrong you can't poke it with a sharp stick or in extremis attack it with a bread knife.
Putting it all outside creates some penalties in terms of appearance,possibly chafe,and windage but when it snags or breaks(as it surely will!)You can sort it.
 
I've got one and would'nt have two cos of reasons mentioned. I'd get turning blocks on the luff of the sail though .. takes a lot of friction out the system
 
I've got the second on the bigger boat. Works brilliantly well - I routinely pull down reefs with the sail powered up (no flogging) . The first can generate all sorts of issues with lead angles, and the load on the tack that is generated when trying to pass the load down to the clew must be grim. We have the benefit of roller cars on the track, and a 4" turning block on the clew. Main area is about 700 sq feet.
 
My experience of the more complex design is that it works perfectly. If you don't have the "balancing" block in the middle of the boom, the differing amount of friction at the leach end form the luff end wouldn't be catered for and an even reef with both cringles correctly pulled down wouldn't be achieved IMHO.
 
I have the second system on a Vancouver 28 and it works very well. The former set-up has the problem that you have to pull all the slack from the leach through the luff cringle and so you can't pull the luff and leech down together.

The second system has worked well for me with no sign of it attempting to jam.
 
I have got the second design, which I think is the standard design used by Selden and have had no problems with it. The internal block is in a track and therefore it cannot twist and jam in any way.
Reefing is easy and I would never consider any other system
 
We used to have a Jeanneau 37, with three single-line reefs based on the first of your systems. We had turning blocks on the luff, and discovered that if the reef was pulled down too far then the blocks could cockle over and jam other reefing lines. In the end we marked the halyard so that in the marked position the turning block was held about an inch above the boom. With this proviso, all three reefs were easy to put in or release.

We have just got a new Najad 380, with a Selden boom fitted with the second system. The arrangement only works for two reefs, though (as suggested in the second text). In our case the third reefing line only deals with the leech of the sail; the luff cringle is taken to a rams-horn fitting. From first experience, it looks as if the third reef will be taken in at about F7-8; not really the best time to go forward.

If you look at the second diagram, you'll see that the maximum length of leech line that can be taken in for a reef is a bit less than twice the length of the boom. Since this length has to go from the end of the boom up to the reef cringle and then down to the boom again, it means effectively that the maximum amount of sail that can be taken off is equivalent in height to a bit less than the length of the boom. Many (if not most) third reefs are deeper than this. We are currently looking at our system to see if a third reef of the type shown in the first diagram can be used.
 
I have the second system inline reefing for the first two reefs and then the third reef uses two seperate lines for the leech and luff - all are still lead back to the cockpit. This seems like quite a good compromise.
 
Lateral thinking

Hi Jonjo

There is always the option of two line reefing which I certainly prefer as it is much simpler, no hidden blocks in the boom to jam and massively less friction. We have such a system fitted and all 3 reefs are handled easily by one person from the cockpit, all 3 reef lines are internal to the boom and in fact we also have a 4th to control either the flattener reef opr the clew outhaul. The total amount of line is the same as for a single line system but as the name suggests there are twice as many lines (but half the length). You will of course need 3 more lines taken back to the cockpit and 3 more cleats or clutches or you could do a trade with say the genoa or spi halyards and handle these at the mast as we do. You don't actually need a winch to pull in the 3 tack reef lines as with the halard 'off' there is no load in them., pull them in by hand and retension using the main halyard. As others have said, smaller diameter lines make for less friction, we use 10mm on a 41ft boat with a large fully battened main and we also have good quality roller bearing blocks.

Robin
 
The second arrangement, as the Z spars, is excellent. The Selden arrangement is the same, except the inboard end does not have the 2:1 purchase by being brought down to the gooseneck level
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