loose main sail luff

bogman

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Hustler 30 standard boat not the SJ version. I raise the mainsail and get the luff tight. The main sail is rigged back to the clutch on the coach roof. The clutch seems to be doing its job and not slipping
With the boat on a beat the mainsail luff slackens a bit as if it was not raised enough. On a run without doing anything the luff tightens up. I have notice that the boat will not point quite as well as previously and put this down to normal wear and tear.
The mast has a bend and alsways did have one. I cannot assertain if there has been a cahnge in this as I never actually measured it.

There is no discernable difference on port or starboard tack and all side stays seem ok.

I am inclined to think the forestay might benefit from a little extra tension...

Any thoughts or previous experience please
 
Never haul the luff "Tight" but adjust it to the wind strength as you sail. off the wind my luff is very slack to get more shape into it, as the apparent wind spd increases so should the luff tension & outhaul.
Most folk sail with luff tensions far too tight. if fact i helped a chap haul is genoa up ( far too much friction & had to use the winch :disgust:) one bar taught he said " that will do for the season" :rolleyes:
 
Hustler 30 standard boat not the SJ version. I raise the mainsail and get the luff tight. The main sail is rigged back to the clutch on the coach roof. The clutch seems to be doing its job and not slipping
With the boat on a beat the mainsail luff slackens a bit as if it was not raised enough. On a run without doing anything the luff tightens up. I have notice that the boat will not point quite as well as previously and put this down to normal wear and tear.
The mast has a bend and alsways did have one. I cannot assertain if there has been a cahnge in this as I never actually measured it.

There is no discernable difference on port or starboard tack and all side stays seem ok.

I am inclined to think the forestay might benefit from a little extra tension...

Any thoughts or previous experience please

Does your sail have a boltrope luff, or sliders?
 
I bet it seems fine and tight when you raise it, but then goes slack once you're on the wind with everything wound in.

What's probably happening is that the downward load on the leech (via the kicker and/or mainsheet) is putting extra load into the halyard and sail and stretching them a bit more.

Try a bit more grunt on the halyard tension and a bit less grunt on the kicker.
 
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I was experiencing a slack luff on my way back from Dartmouth on Sunday. I raised the boom a bit by loosening the mainsheet tension slightly which caused the luff to tighten.

My first reaction to your comment was to ask "why?" But then the cause of the phenomenon became clear to me; when sailing on the wind it is normal to sheet the mainsheet in hard. If one also has a lot of tension on the kicker, (which is not actually necessary when sailing to windward), this has the effect of hardening up the halyard, perhaps stretching both it and the sail. The further you sail off the wind, the less tension there is on the mainsheet, allowing the sail and halyard to relax a little. The purpose of the kicker is to keep the boom down when the mainsheet is sheeted out. If the kicker is not progressively tensioned for downwind points of sail, there is an appearance of slackness in the luff as well as too much twist in the leech.
 
Bogman, not related specifically to your post but are you aware of the Hustler Owners Association? Easy to find on facebook, you just have to ask Andy to add you as a full member... it's free! I have a Hustler 30 too and have found it to be a great source of info and advice. If you can't find it just PM me and I'll send you a link.
 
To me its pretty clear that the downward component of the mainsheet is the cause.

If you try and centerline the boom upwind without pulling the traveller upwind the amount of downward tension needed will be huge.

I think Halyard stretch is the first thing I'd investigate.

As said above do make sure you are not over tensioning the luff, ensure you can twist the luff 90 degrees with finger and thumb.
If you can't its too tight.

As a eliminator next time you hoist the main use the topping lift as well as the main halyard on the head of the mainsail.
Make sure you have similar tension on both and then see if you get the same issue.

I doubt the kicker will be the issue otherwise the tension would remain no matter what angle the boom.
 
Same happened when i bought a new main from Hyde. I realised then how stetchy my halliard was. Changed to a dynema one of lower diameter (from 10 to 8)
This reduced hoist & lowering friction & solved the stretch problem
The luff goes slack to windward because the tension on the leech unbalances the triangle pulling on the head of the sail thus slackening the luff
 
You only pull on cunningham to reduce power to stave off chucking the first reef in.
Tightening the luff either with the halyard or cunningham will also ease off the leach tension again easing power and will stop you pointing as well.

More backstay tension on a masthead rig with lower shrouds really doesn't do much to the mainsail.
It'll increase forestay tension reducing sag and increase mast compression.
If the lowers are doing their job it shouldn't effect mast bend much at all.
 
You only pull on cunningham to reduce power to stave off chucking the first reef in.
Tightening the luff either with the halyard or cunningham will also ease off the leach tension again easing power and will stop you pointing as well.

More backstay tension on a masthead rig with lower shrouds really doesn't do much to the mainsail.
It'll increase forestay tension reducing sag and increase mast compression.
If the lowers are doing their job it shouldn't effect mast bend much at all.

I will challenge you there-- tightening the halliard eases leach tension !!!!
Does it??
 
Hustler 30 standard boat not the SJ version. I raise the mainsail and get the luff tight. The main sail is rigged back to the clutch on the coach roof. The clutch seems to be doing its job and not slipping
With the boat on a beat the mainsail luff slackens a bit as if it was not raised enough. On a run without doing anything the luff tightens up. I have notice that the boat will not point quite as well as previously and put this down to normal wear and tear.
The mast has a bend and alsways did have one. I cannot assertain if there has been a cahnge in this as I never actually measured it.

There is no discernable difference on port or starboard tack and all side stays seem ok.

I am inclined to think the forestay might benefit from a little extra tension...

Any thoughts or previous experience please

Of course the luff will slacken abit . Everything stretches under load. As indeed will the standing rigging. So you need to adjust luff tension going from downwind to upwind if you are a perfectionist. Using things like dynema halyards will help.

Cant see that foresty tension will alter this. Have you checked that the sail luff rope is ok and well sewn to the sail?
 
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