Lack of tension in tack of mainsail

KompetentKrew

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I think the post title describes my problem correctly - I can't get the wrinkles out of the bottom of my mainsail, at the front.

Even if I haul the mainsail halyard so right that it's making pinging and creaking sounds, to the extent that the line feels distorted by the tension once I take it off the winch, I am still seeing this.

I hope these photos are helpful:

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I'm not sure what that cringle is for - my boat isn't set up for a cunningham, and it looks a bit too high for that, anyway?

As always, I appreciate any advice or suggestions.
 
If the halyard is tight but the bottom part of the luff isn’t, clearly something else is holding the head of the sail down.

Excessive friction in the sail sliders / batten cars? (How easily does it come down?)
Clew end of the boom too low when hoisting, so the leach of the sail is taking the tension instead?
Halyard coming up hard at the masthead before the sail is fully hoisted? For example a too-large knot that jams in the sheave too early, or even an incorrectly-cut sail that’s too long in the luff?

If I had to guess I’d start with the boom angle.

Pete
 
No, that cringle looks to be in a similar position to ones I have seen. Many boats have a sail with a cunningham cringle but no other infrastructure.
A little experimentation with a piece of cord of suitable diameter might reveal some pointers.
Feed one end of your cord through something convenient at the mast foot, ( the shackle securing the kicker, for instance) then make a loop in it. Take the other end up through the cringle and back down through the loop. Pull on the working end until you see the wrinkles flatten, then tie it off (to the loop or the shackle).
If this experiment works for you, you could set up something more permanent with a couple of suitable blocks, one of which should i corporate a clamcleat.
 
First thing is that it looks like the reefing line for the first reef tack is too tight. It should be completely free.
However it is obvious from the pictures that your tack attachment is too long/high. The bolt rope is pulling out of the boom track. The tack eyelet should be in line such that there is no pull on the bolt rope. Either shorten the shackle or I would make /get 2 plates to attach to the pivot point for the gooseneck (the one that allows vertical movement) perhaps with a bend or cut out to clear the boom end. In any case get that eyelet lower. ol'will
 
First thing is that it looks like the reefing line for the first reef tack is too tight. It should be completely free.
However it is obvious from the pictures that your tack attachment is too long/high. The bolt rope is pulling out of the boom track. The tack eyelet should be in line such that there is no pull on the bolt rope. Either shorten the shackle or I would make /get 2 plates to attach to the pivot point for the gooseneck (the one that allows vertical movement) perhaps with a bend or cut out to clear the boom end. In any case get that eyelet lower. ol'will

This. Easing the #1 reef and lowering the tack may be enough.

And yes, that is for a cuninghham. Run the line up through the hole and back down for an extra 2:1 purchase.
 
Tack hook is too high, run a line up to the FIRST cringle, the one about a foot up the sail, and use that if you cannot shorten the hook.

Actually, if you just ignore the "ring" and tape at the bottom of your sail and simply hook the sail directly onto the goosneck, that may be enough.
 
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So, to summarise:

1 - The reefing cringle is too tight. Slacken it off but make sure your halyard is the correct tension and has taken the sail to the top of the mast.
2 - Just because your boat isn't set up for a cunningham doesn't mean to say it shouldn't have one. If appropriate to set and depower your sail correctly, fit one.
3 - Secure the tack of the sail in the correct place (both fore/aft as well as up/down). You would be surprised how much sail performance can be gained/lost with the position of the tack.
4 - Be honest. How old is your sail. If you are looking for good performance you won't have a sail that is more than about 3 seasons old. The older, the lesser performance. I recently viewed a boat that had 20 year old sails that were 'very good'. Yeah, right. They were good for the bin.
 
Yup, tack's too high, and possibly slightly too far forwards. There's no significant tension in the reef line chaps, look above it. Could be that the head of the sail is actually at the top or that the,end of the halyard is at the sheave. If not, then silicone spray up the track may be needed. Actually, if you haven't already sprayed it, do it anyway because it makes life so easy. Then rig a Cunningham! They too make things a doddle, halyard just lifts the sail to the top, cunningham is for tension.
 
looks like the reef tack line is tight and the sail hasn't been hoisted far enough?
As other have said, try rigging a simple cunningham.
 
Yup, tack's too high, and possibly slightly too far forwards. There's no significant tension in the reef line chaps, look above it.

There's some slack in the luff above it, but there's a lot more below. The reef pendant isn't the whole problem but it's definitely not helping. If this picture is after hoisting the sail from stowed, not from shaking out a reef, then I wonder if the OP is "stowing" the reef pendants by pulling them through to the cockpit every time, and then working against them every time he hoists the sail. I've seen it done.

Agree with the advice to ignore (or even cut off) the spectacle rings in the tack, and put the shackle pin through the tack cringle itself.

Pete
 
looks like the reef tack line is tight and the sail hasn't been hoisted far enough?
As other have said, try rigging a simple cunningham.

Does the halyard even reach max height or does splice jam and prevent max hoist? a simple Cunningham is easier to tension lower sail than hauling from top.

PS rig a simple tackle with lightish lines like dinghy stuff as the cunningham tensioner or if a spare winch nearby like for spi halyard, use that, can be let off iff winch needed elsewhere.
 
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We can't see the whole sail.
Sails often get hoisted like this simply due to failure to let off the sheet and kicker adequately.

That looks like a shelf foot, so the precise level of the tack relative to the fronot of the boom will be less important than luff tension and leach tension.
Really need to get the slack out of the luff before having an opinion on the 'knockback' of the tack, ie, does it need to be more or less aft of the gooseneck.
Bear in mind that a slack luff is not always a bad thing, e.g. when off the wind in conditions where you are not overpowered.

Good point about is the halyard actually able to take the tack higher or is it maxed out with the splice in the sheave or whatever.
 
1st off, ignore the stuff about the tack being too high. I don't buy that, looks fine to me. If that was an issue I'd expect a massive crease from the start of the shelf diagonally up to the luff, i.e the foot line being pulled up out of the boom. We don't see that, so I'm not seeing that as an issue.

If the luff tension in the top 1/3 of the sail looks considerably higher, but the bottom looks like that then clearly the luff sliders aren't doing a good job of sliding.... Liberally apply lube and try again, also look for obvious signs of damage on the sliders, replacing if necessary. In general you will get plenty of friction with sliders like that, so you would expect to see a difference in tension as you go up the luff. As others have said, if you can't reduce the friction in the sliders enough (and there is a reason people use ball race cars beyond just looking cool...) then using a cunningham is an acceptable compromise.
Also worth saying that your pictures have the sail well eased, which is obviously putting a sideways pressure on your sliders. I'm sure that this is teaching granny to suck eggs, but If you're trying to put luff tension into that sail on that point of sail, then very obviously it won't go anywhere, as those simple plastic sliders are basically jammed into the mast slot at that point. I would come head to wind, make sure that the sheet, kicker and all reefing lines are completely free and then wind in the tension. I'd also leave the halyard on the winch if possible, all clutches will slip with loads of tension on them and you'll notice it at the bottom first.

But also.... I wouldn't worry too much about this from a cruising perspective. It looks ugly but it's not hurting your performance too badly providing the luff tension is there higher up the sail. Especially on a reach...
 
4 - Be honest. How old is your sail. If you are looking for good performance you won't have a sail that is more than about 3 seasons old. The older, the lesser performance. I recently viewed a boat that had 20 year old sails that were 'very good'. Yeah, right. They were good for the bin.
Can you drop your three season sails round to me and other deserving cruising sailors please?
 
1st off, ignore the stuff about the tack being too high. I don't buy that, looks fine to me. If that was an issue I'd expect a massive crease from the start of the shelf diagonally up to the luff, i.e the foot line being pulled up out of the boom. We don't see that, so I'm not seeing that as an issue.

If the luff tension in the top 1/3 of the sail looks considerably higher, but the bottom looks like that then clearly the luff sliders aren't doing a good job of sliding.... Liberally apply lube and try again, also look for obvious signs of damage on the sliders, replacing if necessary. In general you will get plenty of friction with sliders like that, so you would expect to see a difference in tension as you go up the luff. As others have said, if you can't reduce the friction in the sliders enough (and there is a reason people use ball race cars beyond just looking cool...) then using a cunningham is an acceptable compromise.
Also worth saying that your pictures have the sail well eased, which is obviously putting a sideways pressure on your sliders. I'm sure that this is teaching granny to suck eggs, but If you're trying to put luff tension into that sail on that point of sail, then very obviously it won't go anywhere, as those simple plastic sliders are basically jammed into the mast slot at that point. I would come head to wind, make sure that the sheet, kicker and all reefing lines are completely free and then wind in the tension. I'd also leave the halyard on the winch if possible, all clutches will slip with loads of tension on them and you'll notice it at the bottom first.

But also.... I wouldn't worry too much about this from a cruising perspective. It looks ugly but it's not hurting your performance too badly providing the luff tension is there higher up the sail. Especially on a reach...

It also looks like a fully battened main and the battens may be adjusted too tight and adding to pressure on the sliders. Our last fb sail had roller bearing cars on a track and could be raised easy all bar the last bit because initially the splice taper in the original halyard jammed in the top sheave, winding on more tension just stretched the halyard. Solved by a new Dyneema halyard knotted to the head shackle (I forget the knot name but easy to tie safe and secure as well as short.) I also put a line through the Cunningham to a redundant mast winch ( everything else went back to cockpit coachroof self tailers plus HD clutches. hoisting was easy without using winch handles except for final tweak and very last knockings on the cunning ham THE mainsail was a radial cut one in Hydranet and loose footed. In my case the cunning ham's eye was intended as the tack hole for the flattener reef, and rarely used as such unless set up in harbour prior to departure by hooking on a redundant 'horn'. We had a 3 reef slab main with 2 line reefing and all lines to the cockpit
 
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Does your main sail go up easily or do you need to use the winch before it’s all the way up. I had a similar problem for years and was caused by there being no main halyard sheave at the top of the mast. The halyard was just running over a spindle that used to have a sheave around it. Once replaced the difference was incredible. As other have said poor running sail slides can cause your problem or even a twisted mast.
 
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