putting in single line reefing on a 32 footer - advice about blocks etc

nicappotamus 2

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It's time for me to start smuggling the bits into the house to do this......

I'm converting from an unusual/old school set up on a very old boom. we've converted the main from a luff rope to slides and fitted lazy jacks. there's a slab reefing track near the aft of the boom with two blocks - i think it's the barton slab reefing track and blocks.

the sail has three reef points in it but at the moment I'll go for the first two reefs as single line and probably put seperate tack and clew lines for the third reef otherwise it'll be too much string - but that's for later.

I would just like to ask how others have done this. Do we think that I can tie (using dyneema loops) low friction rings to the tack and clew reef points and use these as blocks or should I use roller bearing blocks - and is it ok to use a dyneema loop to do this. I wonder whether this arrangement would cause a lot of chafe on the sail?

So my plan is to take the reefing line from the boom end, through whichever block we choose on the clew of the sail, back to the boom and around the barton block and then forwards.....this is where it gets hazy for me planning it out.

at the front end I need a turning block on the boom (I'll need two of these) for the line to go up to the reefing tack reefing point, through whichever block, and then back down - do I go through a bullseye on the mast so that it provides a positive "stop" for the tack? And then through a turning block at the base of the mast so it runs back along the deck (was thinking again whether a low friction ring preferably to keep cost down).

So in summary my questions are:

1. low friction rings or roller blocks on the tack and clew reef points of the sail and do I need to worry about chafe on the sail from them?
2. i guess it's ok to fix the block to the sail using a dyneema loop through the reefing eye/pennant
3. what sort of turning block at the mast end of the boom? - I'll need two so space will be an issue - if it's all done with low friction rings then it's easy enough to rig dyneema shackles and a dyneema loop around the foreward end of the boom.
4. bullseye on the mast?

so I guess it's some advice from people who have done this before as a retro-fit (on a budget as usual). Luckily it's an IOR influenced sailplan so the main is small in relation to the genny.

thanks!!
 
fwiw I had single line in-boom Seldén reefing on my Sadler 32 which I realise is a bit diferent from that you're proposing . It was not very successful even after rigging low friction blocks on the tack and clew where there had previously been 'low friction' rings. It seems to me there's too much potential for too much friction in a single line system and once the reefing lines have a bit of salt in them and stiffen up the whole thing can becomes too hard to move, especially as when you want to reef it's a time when you really do need rely on it it moving smoothly and easily. I also worried about the strain I was putting on the turning-block fixings - if one of those let go in a blow and dumped your reef into the blow...there's a lot more to go wrong with single line. I prefer KISS!
You'll gather I'm not a fan. I know some-many people are happy with theirs but I think the potential for ending up with a vital safety system of questionable performance isn't something I'd do again.
Suffice to say that as soon as I re-rigged it with a conventional reefing line to the leech and rams-horn and bullrings at the luff the boat was transformed in terms of effortless reefing performance. If I really wanted to eliminate going to the mast I'd look at two-line system and accept the extra cordage.
If you do go down that line I'd suggest not skimping on the blocks, certainly don't use the smallest possible, upsize them to reduce friction. I'd use bb blocks, not plain and do everything to keep the number of blocks and turns in the system to the absolute minimum.
 
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I tend to agree that single line reefing demands the lowest possible friction and even then may not succeed in snugging the reef in tightly. A two line system using blocks (not low friction rings) will allow you to pull the tack and clew in tightly for a well setting sail.

For a low friction ring to live up to its name it must offer a sufficiently large radius for the rope to glide over it - that would make it enormous! Other than light or no load applications I think of these rings as marketing carp. In my youth it was not unusual to use a wooden ring in a similar manner, but it was recognized that once loaded they do not adjust easily. The manufacturers' reference to marine grade aluminium and hard anodizing are rubbish! There is no such thing as "marine grade" and you either anodize aluminium or you don't (and it's not particularly hard!).

It will help tremendously in taking in a reef if you have an independent means of supporting the boom, either a topping lift or a spring kicker.

Rob.
 
Personally if starting from scratch on a 32 footer I would not go single line reefing but instead use hook downs for the front and conventional reefing lines at the back, simply threaded through the sail reef eye. That’s what we recently fitted for reef 3.

Having said that, our current boat (c 40 foot large mainsail) came with single line reefing for first two reefs, and this works fine.
No pulleys on the sail - outer rand just threaded through the sail and front end through large s/s eyes attached dog-bone style through the reef point (threading through the sail at the front does not work due to friction). Precedes low friction rings which would be even better.
Use of 8 or 10mm cruising dyneema for reef lines is important for this. Low stretch and lower friction.

We don’t have the Selden style pulleys in the boom. As rigged from factory rope goes up from boom end to sail, back down round boom end pulley, up to tack ring, down to deck via in line fairlead at tack height (critically important) then led aft.
Used extensively and simply works.
 
We have a system similar to that you're planning and it works OK so long as you're not particularly fussy how tight the reefing lines hold the sail. Initially I had a double turning block for reefs 1 and 2 at the mast, but the lines pull at different angles and cause extra friction. Much better with individual blocks for each reef.

We use 8mm braid clad Dyneema line and it's strong and supple enough for the job. When dropping the main we always leave the reefing lines loose so they don't have to pull through each time you put up sail.
 
I found I needed blocks at the luff reef points, but got away with going through the eyes at the leach on my 24 footer. For the forward end of the boom, I was converting from roller reefing, so had a square hole where the handle went to wind a reef in; an eye bolt and eye nut through this hole worked perfectly. Without that, I'd have fixed eyes to the boom to take the blocks. I reckon 4 x 5mm monel rivets would be plenty, as the load is in shear, but I'm not an engineer, so the usual caveats apply.

The main thing is to use decent roller/ball bearing blocks, not sleeve bearing ones.

I have to disagree with dunedin about using hooks at the mast. When you want your second - and especially your third reef, it's no time to be going out of the cockpit. On that subject, a light downhaul on the main that allows you to pull it all the way down and keep it there is useful. Before I had the ability to drop the main from the cockpit, there were a couple of times when I would have preferred to get rid of the main and use a bit of genny, but really didn't want to go to the mast, so I ended up with the main, which was less than ideal.
 
thanks guys. I am having a root around in my boxes as I think i've got some low friction rings so I can have a cheap n tearful punt at it - was going to use dyneema for the lines :) then we'll go from there with roller bearings if needed. I think I'll get it to work on the first reef before moving upwards. I'm trying to save a bit of space on the clutches - so if all three reefs are going to come back to the cockpit then I'll need at least one single line one to have enough clutches....

reason for trying with the single line, as much as anything was that back surgery about 14 months ago made mobility an issue up until recently (and even now I have my good and bad days) so I'd rather plan for something like that rather than assume that I can leap about the boat like a spring chicken

Steve - that's a good idea about the light downhaul - a friend had it on his boat and it's really handy and it's on my to do list :)
 
This is how I tackled this problem.

http://www.myhanse.com/single-line-3rd-reefing-setup_topic10548_post88610.html?KW=reefing#88610


and I think there is a bit more info here

http://www.myhanse.com/cunningham-and-outhaul_topic5417_page3.html?KW=reefing



On my latest main, I have sewn in pulleys on the 3 luff reefing points and on the 1st and 2nd leech reefing points and just a eye on the third reefing point so I can still use a soft shackle to attach the 3rd reef line when I think it may be necessary.
 
I've tried todo exactly as you propose but it just didnt work. There seems to be too much friction and I couldnt get the sail to set right.
I now just have one line for the clew and another line for the tack. Ive cut off the rams horns as they got in the way. I now only have a 2nd reef. I dont race so going to a second reef straight away avoids extra work and if thats too much I take the main down and sail just on a reefed genoa. If thats too much its just the engine. Easy life.
I also have a downhaul (6mm) run through a tie wrap at each car on the sail so that I dont need to go on deck till the sail is right down and just needs tying.
 
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