Mainsail luff stretch - remedy?

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Oct 9, 2008
1,742
Bristol 29.9 Dana Point
Hi,

My mainsail luff is stretched to the point that the tension is no longer on the tack grommet, but on the foot boltrope instead. This is causing the sail material to be removed from the boltrope at that location, and chafing the rope on the boom where the boltrope inserts.

Not only is it damaging the sail, but I can't get the right luff tension all the time in different conditions.

The sail is in good condition otherwise.

I can't see any remedy other than punching another hole higher in the tack. Or, a Band-Aid fix such as using the Cunningham grommet to run a tension line. Any easier remedies? I ask because there are so many times that others have ideas even when I think there is no other remedy.
 

RichH

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Feb 14, 2005
4,773
Tayana 37 cutter; I20/M20 SCOWS Worton Creek, MD
Suggestions

1. inspect to see that the stitching (thick 'twine') that is hand sewn 'into' the boltrope has not become loosened/broken, thus allowing the sail material to 'stretch'. This 'hand stitching' is located on the boltrope sleeve near the head and at near the tack.
2. ditto #1 but broken/parted boltrope. The hand stitching 'connects' the boltrope to the luff sleeve'.

PM me if the boltrope has parted/slipped and you need the 'relaxed' dimension of the boltrope and you yourself will be doing the repair (sailmakers needle and 'waxed sailmakers twine') ..... the normal boltrope 'preload' (shortening) is 1" for each 10-11 ft. of 'designed' luff length for woven dacron sails.

Even in a worse case scenario ... and if the 'reinforcement patches' at the head and/or tack havent ripped etc., you or your sailmaker can apply a connection cringle - that bypasses or 'bridges' over any tears or weakened sail material using flat single ply webbing and "D" rings to reconstruct to the proper (un-stretched) luff dimension.
Use your cunningham, to get proper luff tension until you can make such corrections - if the 'damage' is near the tack of the sail. If you find damage near the head, then sailmaker or DIY repair.
Usually such 'sudden elongation' of luff or foot dimensions is the result of broken sail twine that binds the boltrope to the boltrope sleeve .... slipped boltrope.
 
Oct 9, 2008
1,742
Bristol 29.9 Dana Point
Thank you,

There's no boltrope in the luff. It's a hank-style with slides. There is boltrope in the foot, which is the one chafing on the boom near the tack now that the luff has stretched.

The stretch likely occurred over time. The sail was in this condition when I purchased the vessel.
 

RichH

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Feb 14, 2005
4,773
Tayana 37 cutter; I20/M20 SCOWS Worton Creek, MD
Very strange .... possibly a mainsail that was converted from a 'furling' configuration. Even with a mainsail on a furler there 'should' be a 'continuous support tape' .... two 'small' cords sewn into the 'luff tape' to prevent undue stretch.

Woven dacron Hank-on sails or sails that attach with 'slugs' or 'slides' usually have a boltrope ... a 3 strand dacron rope thats covered by a sleeve, sometimes the boltrope directly sewn to the sail fabric (on ultra-quality sails).

Got a pic of the luff configuration of this 'beast'?
 
Oct 9, 2008
1,742
Bristol 29.9 Dana Point
I don't have any pictures of the sail that would adequately portray the luff or issue. The entire sail inventory (Main, Genoa, working jib, spinnaker) are original Hood sails.

There may be a tape or other support in the luff. It is slightly stiffer there. Definately no rope.
 
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