No Luff Tension

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MASH

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I've long had difficulty getting decent luff tension in my mains'l, and hoisting the genny (Bamar roller furler) is always a battle. (Sadler 32). The main haly'd is tight as an iron bar at deck level, yet I get poor tension in the luff which doesn't seem rational.

I recently looked at the sheaves at the foot of the mast, and saw they were deep-grooved as if for wire and that the halyards are far too large diameter to fit them properly, though the overall width is OK.

It occurred to me that the deep-grooved sheaves (plus those that may be the same at the masthead) might be nipping the halyards under tension and causing them to jam rather than rotate and pass on the strain.

Any thoughts, or similar experiences?
 
It would be easy enough to change the sheaves at the foot of the mast but have you thought about the problem being with the sail? Is it the right sail for the boat or is the luff too long? Is there any further that it could go up the track? If not you could have the sail shortened.

I don't know the Sadler but presume the boom is in a fixed position and can't be dropped.

I don't know about the sheave shape but I can get my main up with the luff fairly tight without using a winch so I wouldn't have thought that friction or jamming on the sheaves was where the problem lay.
 
Is the sail taught anywhere else (ie between head and clew or head and centre of boom?) If so this might be an indicator that the other controls need playing with...

Some sails needs the kicker and mainsheet letting off considerably to get the luff tension sufficient.....

Also, is the headboard/cringle hitting the mast head? it maybe that the sail has stretched (or was sized wrong to start with) and the luff is longer than the track... do you have reefing cringles on the luff?... if so, can you get sufficient tension on the luff using them instead of unreefed - if so might indicate an over long luff length...

Sorry if i'm teaching grandma and all that, but worth asking the obvious questions I guess?
 
Is it possible that the bolt rope of the sail has shrunk? This would have pretty much the same effect. Can you get a sailmaker to have a look?
 
Another problem I've seen is the splice in the main halyard being too long and jamming in the masthead sheave, particularly as you say the sheaves are for wire halyards. Do you get tension when the sail is reefed? If so this would suggest that the problem isn't with the sheave sides spreading under load and jamming.
 
Or taking it further hoist the main halyard with just a spare line attached. See if the halyard alone gets right to the top sheave. Then try making the line off at the bottom of the mast and tension the halyard against it. Does it bind up or does it tension the line ?
If that's all fine go back the other suggestions about headboard. Does it have a bolt rope or is it sliding slugs. Is the luff groove nipped anywhere and jamming a slug?
I had a similar problem on my Foxcub and it took ages to find the answer.
The Headboard had two tapes to two slugs. As the headboard approached the top sheave it was pulled in against the mast because the halyard exited the sheave too close to the mast and the previously parallel tapes twisted so that the slugs were not in line and jammed in the groove. Luckily I had a spare hole in the mast head crane and could move the sheave further out so the halyard pulled the headboard up the mast vertically instead of pulling it in.
This is the After shot

(It was my own fault for changing from bolt rope to slugs)

Headboard.jpg
 
a main,sl luff should "only just" be tight enough to allow the luff not to sag when "on the wind". increase halliard tension as apparent wind increased to reduce healing moment.
off the wind allow the luff & foot to be looser to induce more depth @ max chord
 
Hi Mash:

I sail a 34 and it has wire halyards for both the Main & Genoa with rope tails spliced in, this is standard for all 34’s and consequently the sheaves are laid out accordingly I don’t know about the 32 but would suggest you post the same question on the Sadler site… www.mikelucasyachting.co.uk

I am sure there will be several 32 owners who can offer their experiences, and if all fails, email Mike Lucas from the site link, he will be able to confirm at least what type of halyard & sheave the 32 was set up with.

Have fun… Peter
 
I had the same problem. The sail was too long but after It came back from the sailmaker I still had a problem. It turned out the luff rope was too short. I disconnected this from the tack and bingo up she went. I have since added to the luff rope and restitched.

Might also be your halyard is too stretchy, especially if original was all wire.

Lay on the deck with binoculors and have a good look. If the headboard is not up against the top sheave try removing the shackle and tie the halyard directly to the headboard.

release the tack and see if you can get the sail up further this will tell you if it is the sheaves on top or the luff length.

Good luck.

Tony.
 
I reckon that even the best spectra rope will stretch after a few minutes of sailing. Wire with a rope tail is the best for stretch.
You have got lots of good advice. Either the luff is too long for the available space or the luff is jambing somewhere up the track or there is a load from the back end of the sail vang or main sheet.
You certainly need to fix the problem. olewill
 
the other issue could be that at some time the boat has lost a halyard and when re-installed it has been wrapped round another halyard on its way down the mast. In that case the friction when hauling up can be very high - happened to me once and it became a low gear wich job to even hoist the genoa.
 
I have been using Spectra halyards for many years and never experienced any significant stretch .Wire used to be the thing but I can see no difference in pratice.
 
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