Reducing reefing line size from 8mm to 6mm

Gixer

Gixer

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Looking to reduce friction and am thinking of reducing my reefing lines from 8mm to 6mm. I have standard slab reefing running back to the cockpit where I have jammers and a winch. The jammers can take this size line and the winch should make it ok to handle.
the boat is only a 27f yacht, not sure about the size of the main.
Anyone done this on this size boat. I’ve searched on here but can only find one reference.
Thanks
 
We did it on an X99 years ago. One route is to simply remove all the existing lines and replace with dyneema lines one size smaller. The other way is to keep the existing lines and strip off the outer cover retaining enough (length) of the cover to allow ease of handling and ensure the clutches and winches are easy to use and effective. You need to splice the remaining cover into the remaining core. You need to assume that sometimes you will be reefing whole or in part by hand - not using a winch (because it is already doing something useful) so keep the tails such that they can be managed by hand.

None of this is difficult, it does reduce friction (and makes reefing easier and quicker) it also makes it easier to let a reef out. It also saves weight - but for most that is not the issue. The dyneema option is actually the best - but expensive.

If you strip covers off - keep the covers - they can be useful to add an extra cover if you have any abrasion, sleeves for mooring lines, snubbers etc - but depends on the relative sizes.

We have done the same with our 38' cat and use 6mm dyneema for our 3rd reef in the main. Its a big reef, reduces sail area by 75% so there is a lot of rope. In 10mm the sheer volume of the rope when fully reefed was daunting, you need to store it, reducing as much as possible to 6mm has made a world of difference. We have spliced a 10mm tail onto the reefing line to allow it to be used sensibly in the existing clutch, winch and by hand (as initially you are simply hauling in lots of rope). We also have a short length of 10mm line spliced into the 'middle' where the line reaches the clutch, so its a complex bit of construction. We have found 6mm dyneema manageable by hand, with gloves. We find we use the 3rd reef frequently (and seldom use the first reef - which is a bit small).

Jonathan
 
I would be a bit leery of replacing 8 with 6mm. The clew line particularly takes the load of the main sheet so is subject to stretch and possibly chafe. (if you use the sail eyelet as a sheave.) Yes dyneema will reduce stretch but may still suffer from chafe. anyway give it a go if you want ol'will
 
Gixer said:
Looking to reduce friction and am thinking of reducing my reefing lines from 8mm to 6mm. I have standard slab reefing running back to the cockpit where I have jammers and a winch. The jammers can take this size line and the winch should make it ok to handle.
the boat is only a 27f yacht, not sure about the size of the main.
Anyone done this on this size boat. I’ve searched on here but can only find one reference.
Thanks
Click to expand...
8mm polyester to 6mm dyneema is an easy swap strength wise.
 
Dyneema is very chafe resistant and much more chafe resistant than anything else you might use, assuming the point where chafe might occur is 'smooth', say a stainless steel eyelet. Moreover if the reef is strapped down tightly - there is little movement. It is correct that you will not need the strength of 6mm dyneema - but anything thinner will be more difficult for most to accept (heart over data). Additionally I have not tried dyneema smaller than 6mm (for any application) and I will not suggest something I have not tried. The only small line we have used was 2mm kevlar for lightweight spinnaker sheets - but hardly comparable.

The major downside with dyneema is cost.

On our cat we use small blocks, strapped to the eyelet holes. - but our main is 45^2 - and I doubt is needed on a 28' yacht.

Jonathan
 
Neeves said:
We did it on an X99 years ago. One route is to simply remove all the existing lines and replace with dyneema lines one size smaller. The other way is to keep the existing lines and strip off the outer cover retaining enough (length) of the cover to allow ease of handling and ensure the clutches and winches are easy to use and effective. You need to splice the remaining cover into the remaining core. You need to assume that sometimes you will be reefing whole or in part by hand - not using a winch (because it is already doing something useful) so keep the tails such that they can be managed by hand.

None of this is difficult, it does reduce friction (and makes reefing easier and quicker) it also makes it easier to let a reef out. It also saves weight - but for most that is not the issue. The dyneema option is actually the best - but expensive.

If you strip covers off - keep the covers - they can be useful to add an extra cover if you have any abrasion, sleeves for mooring lines, snubbers etc - but depends on the relative sizes.

We have done the same with our 38' cat and use 6mm dyneema for our 3rd reef in the main. Its a big reef, reduces sail area by 75% so there is a lot of rope. In 10mm the sheer volume of the rope when fully reefed was daunting, you need to store it, reducing as much as possible to 6mm has made a world of difference. We have spliced a 10mm tail onto the reefing line to allow it to be used sensibly in the existing clutch, winch and by hand (as initially you are simply hauling in lots of rope). We also have a short length of 10mm line spliced into the 'middle' where the line reaches the clutch, so its a complex bit of construction. We have found 6mm dyneema manageable by hand, with gloves. We find we use the 3rd reef frequently (and seldom use the first reef - which is a bit small).

Jonathan
Click to expand...
I like the idea of reducing the mass of the reefing lines by removing their outer covers from clutch to boom. However, have you ever considered removing the cores instead? I have done that on my foresail furling line and found it to work well, with the advantage that there is no need to tie the core to the cover.
Mike
 
mikegunn said:
I like the idea of reducing the mass of the reefing lines by removing their outer covers from clutch to boom. However, have you ever considered removing the cores instead? I have done that on my foresail furling line and found it to work well, with the advantage that there is no need to tie the core to the cover.
Mike
Click to expand...

Our problem with furling line was that the furling drum was too small for the amount of rope needed of the diameter supplied. We downsized it to 6mm dyneema, no cover, with a 6mm, polyester, tail to allow handling (uncovered dyneema is VERY difficult too handle by hand).

Confess it never occurred to me to use the cover - but it would work, good idea - a use for removed covers!

We have used outer covers made from dyneema as abrasion sleeves.


These ideas are not mine

We bought our dyneema for our X99 from Bridon, they sold their leisure rope business to .....Marlow?. Bridon had supplied to Rothmans and Rothmans had stripped the covers off their dyneema reefing lines. This was in the early days of dyneema and they only removed the covers where the ropes were in the boom - as at that time it was thought dyneema was susceptible to UV. Amazing what a little testing and data will do to remove unfounded doubts!

Rothmans won the race, we were very average.

Jonathan
 
Thanks for the responses guys.

I think I will give 6mm a go. I'm not too worried about chafe as with my sailing experience I only day sail at the moment so could keep an eye on the lines.

The breaking strain is a thought though, standard 6mm 850kg, 8mm 1400kg, 6mm dyneema 1100kg. How on earth do you work out the forces on the main??
I don't mind buying dyneema but don't want to spend twice the money if a good quality double braid polyester 6mm will be fine.
 
Much cordage on smaller yachts is sized not for strength but for ease of handling. So the fact that you currently have 8mm is, very, unlikely to be for strength but once you get down to 6mm it can be tough on hands, especially hands unused to 'manual' work. The tension on a reefing lines is, or should be low. Nowhere near the, approx, 1t you are taking of in terms of spec - but these are breaking loads, not the loads on your main and your 1,400kg 8mm that you want to replace is there because its comfortable in the hands.

I'd go the economy route and option the 6mm 650kg polyester - unless you can source reliable and cheap dyneema. When we downsized we were worried about weight, that was the motivation on our X99 (we changed all the halyards and sheets to dyneema along with the reefing lines) and for our cat our motivation was the same as yours - to reduce friction and makes the lines easier to run. But we chose dyneema because our sails are quite large (and 6mm quite small).

Jonathan
 
Thanks, i'll have a look.

My boat is a British Hunter 272 so a 27 foot fractional rig.
 
Dyneema, without a cover is very slippery, if you decide to use it, make sure you cleats and/or clutches will hold it under load.
I used 6mm dynema with a braded cover on my Parker 275, it worked very well and eliminated the stretch, which was irritating. With the polyester rope, I'd set up a reef and tension the luff, only to find everything had gone baggy and slack.
 
What sort of blocks are you using? I had too much friction with cheap, sleeve bearing blocks, but things got a LOT easier when I changed them for better, ball bearing blocks. Checking the blocks would be my first step.

As for going down a size, strength won't be an issue, but handling 6mm line may be uncomfortable when you're pulling hard. ISTM that any of the options intended to make handling easier are going to be a fair bit of faff setting up. and will have to be go a long way down the line - pulling in reef two tends to involve a lot of string!
 
Stemar said:
What sort of blocks are you using?
Click to expand...

The only block I have is at the bottom of the mast which the line then runs though eyes to the jammer, there are sheaves in the boom.

Just used the Harken guide and all the numbers seem to be coming in well under the breaking strain of standard 6mm braid on braid. Think i'll find a very low stretch braid and go for that.
 
The 'clew' (when reefed) end of the reefing line will be under the load of the kicking strap (aka vang) which will be far greater than that of the mainsheet. On our (non-racing, 32') boat the reefing line needs a lot of tension just to keep the boom snug up to the reefing point and the foot of the sail reasonably tight. This is because the reefing line attaches to the boom just aft of the reefing point on the sail, then goes up through the reefing point and back to the sheave in the outer end of the boom - it's the standard arrangement but requires a lot of tension in the line to avoid the boom drooping. If I were resizing to 6mm I would definitely use dyneema.
 
Obviously, this probably depends on the reefing gear fitted. However, my Furlex gear is quite sensitive to the diameter of the reefing line, and only really work correctly with size of reefing line specified by Furlex - too large and you can't get enough turns on the drum, too small and it jams easily. If it's Furlex gear, I'd use the size they specify, as anything else could well give you problems.
 
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