Main sheet system

DoubleEnder

DoubleEnder

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Currently I have a 4 part system using old tufnol blocks. The combination of 300 sq ft sail, high friction and old line, combined with my weediness, makes for inefficient trimming. Also breathlessness and general feelings of mortality.

So I am going to upgrade to a more modern 6 part arrangement.

I could fit an Easymatic system http://www.force4.co.uk/8691/Easy-matic-2-Two-Speed-Mainsheet-System.html for £275. Double ended to give a sort of coarse/fine possibility.

I could use Barton size 5 blocks http://marinestore.co.uk/Barton_Block_Size_5_Ball_Bearing_Triple_Swivel___Cam.html
Would cost about £130 I think, for the two blocks

I could go Lewmar Synchro http://www.westmarine.com/webapp/wc...&subdeptNum=50057&classNum=50064#.UURSbzePPvg. I think this would come to about £200.

Or I could go with Harken http://www.harken.co.uk/productdetail.aspx?sku=1556. Scary prices, probably £400 or more.

I am going to use 12mm line, and the boat is a 34' fractional sloop, 24' waterline, displaces about 5.5 tons. She's heavy and stands up to her sail so I want meaty gear. But she is also wooden, with a nice mahogany cockpit, and a bronze main sheet horse so I dont want too hi tech, I think. And funds are not unlimited

Any recommendations, experiences, other suggestions?

Thank you

Graham
 
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Seriously think about using 10mm line for a 34' boat, I know its not so comfortable in the hand, but its a lot less volume of line to get in the way,and you don't handle the main sheet that much compared with the genoa.

Plank
 
My Boat is a Dehler 34 and have similar main sail size, boat lenght and weight as yours.
I have been using the Easymatic system since I own the boat from 1985. No complaint, cost effective & easy to handle.
The 3:1 provide fast sheeting in/out and the 6:1 give easy fine tuning. It has ball-bearing pulley and lines runs smoothly.
With end-to-end spliced on the sheet is really convenience for operation.
I use 10 mm double braid main sheet and is Ok for the 33 sq m main sail (I race the boat quite often but here seldom blow over 20 kns).
I did use 12mm D/B sheet but it was too much friction on the blocks and not as smooth as using 10mm sheets.
You may consider 10 mm spectra line if you want stronger rope to cope with strong wind.
 
No joy with the used Easymatic then?
Just for interest, what puts you off the Nautos blocks I pointed you towards that would be about £100 if I recall? I think they are quite decent, I would rate them above the Bartons. Not as pretty as the Lewmars.
 
If you are considering blocks by Barton, Lewmar & Harken, take a look at the Selden range of blocks. I have several Selden blocks on my boat and they seem to be a very good price to quality compromise. IMHO better than Bartons and just as good as the other two makes.
 
Perhaps start with new, right diameter line? I'd say for 12 mm blocks 10 mm line will get least friction. Line that is pliable and bends well, but not getting flat in bends. Tufnol can be soaked with thin machine oils; or may try some new ideas like PTFE spray. May happen this will be enough, at no cost. There is also possibility of changing arrangement, lead etc for more convenient, if possible.
Change to 6:1 may mean more line, more friction and more inconvenience, so I would not be in a hurry, unless you are sure about it. I was quite happy with 50 sqm main on 4 part tackle.
Assuming blocks are good (sheaves and axles not worn) not so much improvement can be gained by most expensive hi-tech kinds, we're not talking many tons here.
What I can recommend for new ones - take simple ones, big diameter, and meant for line next size up than will be used. It's all about sheave diameter and line feeding in.
 
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Norman_E said:
If you are considering blocks by Barton, Lewmar & Harken, take a look at the Selden range of blocks. I have several Selden blocks on my boat and they seem to be a very good price to quality compromise. IMHO better than Bartons and just as good as the other two makes.
Click to expand...

+1, I was actually thinking Selden when I remarked on Lewmar in OP's post!
 
Where does the mainsheet attach to the boom? at the clew end the mechanical advantage is a lot better than one taken to the bridgedeck or worst of all to the coachroof. However the better leverage at the boom end is compromised by having to feed out a lot more sheet on the run and pull the same in as you come up onto the wind.
 
Thanks everyone. I think I am going to go in stages. First I'll take Rossynant's suggestion, clean and lubricate and check out the blocks. Then I will change to new 10mm line. Maybe I'll get enough for the 4-part set up, or maybe I'll get enough for a 6 -part just in case..... I'll take a look at what I can use the spare for and make the decision as to how much to buy. But I'm always keen for a cheap solution. That doesnt work, I will look again at the Selden blocks suggested by Troubador.

Boom end attachment, BTW

Graham
 
My main is 24 sq m with 6:1 sheeting (Nautos ball bearing blocks, 10mm rope) nearly at the boom end - sail foot is 4 m - and just before we reef at 18-20kts it is very heavy.
If Rossynant does 50 sq m on 4:1 he should be entering world's strongest man I reckon!
 
You could consider a 4:1 with a 4:1 fine tune.
Less rope to shift and plenty of power for the last bit where the weight comes on it.
Also, good ratchet blocks are worth having, as are good cleats.
 
Troubadour said:
If Rossynant does 50 sq m on 4:1 he should be entering world's strongest man I reckon!
Click to expand...
I don't now :D Got a small ketch, with very handy small main - around 22 sqm, 4:1 tackle. So to have it easy with my broken back.
But yes, was going on bigger one. Getting it hardened in a blow required some squarerigger methods of heaving down on fall from tackle against a cleat (however this should be called in English) but perfectly possible, because bodyweight is used; this depends naturally on general layout in the cockpit. Well, about F7 this was getting hard, must admit.
On some boats there is no way to hang on the line, even to brace against something so to be able to pull at all...
But I just like simple, with less rope to get entangled with.

edit - looked over links OP provided. Barton offers sheave of 45 mm for 10 mm rope. :confused: Others similar. Whatever happened with recommended sizes for efficiency? 10 x rope for twist/plait, 8 x for braided...
This may explain difference in opinions here.
Friction makes threefold tackle not much improvement over twofold really, unless the blocks are very efficient, minimum friction possible. As said, it's not so much friction in blocks, but bending of the rope. Just using good size sheaves instead of this smallish yachty stuff can make twofold one more efficient :)
 
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Do you mean swigging? Puling sideways then quickly taking the slack out?
My 6:1 10mm is on 57mm Nautos ball bearing blocks - quite decent I think.
 
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No, though this can give some 10 times purchase actually. I'm speaking about using your body weight onto the line, instead of just hauling with the muscles of hand only. If you can conveniently pull on the fall down, or even horizontally - makes a difference and is not tiresome.
Pulling the line from down up, as in common set-ups, is the hardest way. My doctor actually forbids, this could break your back... :p

It was considered that for good efficiency (reasonably small loss for rope bending, distortion in it) 10 times rope diameter is good size for sheave; 5x is a practical minimum for safety... that cause a loss but will not damage the line and break it :)
Loss of purchase (on one sheave) can be from 10% to 50% in practice, Iirc. So single purchase (2:1), with two sheaves will really give around 1.5:1 at pulling on line (not talking load on end when static); you have 6 sheaves, imagine.
Friction on a sheave bearing itself is not as much important normally as 'friction' in line itself; bearing gets more important with high loads only, but in multiple purchase load is divided.

Another tip when having 4:1 tackle on boom end - easiest improvement is to install simple single block on a boom somewhere about, additional. Snatch block may be smarter. This can be another simple idea for OP.
When things get hard sheet end can be put into - makes 6:1 purchase (but without the friction of another sheave down) and sheet may be pulled down from boom, much more easily and efficiently, not to mention it could be pulled from any place convenient you happen to be in. All is then needed is some cleat to fasten it.

Arrangement most common now - like in OP's links - is taken from small racing dinghies, where blocks were attached down, below crew position. Well, in fact nowadays yachts are small racing dinghies blown up in size, but. There is a cam cleat on lower block, but arranged in not a smart way - its made to pull on sheet up, and choke it down into cleat.
On cruiser cam cleat standing vertically is way to go (if any camcleat at all), so to say upside-down mounted - sheet end gets jammed going up vertically, and is released from grip by pulling it down, to horizontal, out of jaws. Usually the track is quite up, deck, even on coachroof. So can be pulled towards you, swinging your body to do it, then get it into cleat. Also I'd advise against having an eye on cleat there, holding line into the camcleat all times - not so safe idea, it can grip the sheet when not intended...

This is tackle I was talking about, for big main, 4:1. Note camcleat mount "upside-down" - jaws are no longer there, were not convenient in fact as not so trustworthy, this is powerfull boat carrying sail in big blows. Sheet is cleated on normal cleats at sides of cockpit. Tuffnol blocks, quite old, still good. View attachment 29769
 
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