Bizarre way to flatten a main

Ruffles

Ruffles

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Boat: Portsmouth, Us: Stewkley
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Our old main is due for renewal as it's pretty baggy and impossible to flatten. However when we first used the thing at the beginning of the season it seemed to have magically improved - until I noticed I hadn't attached it at the tack! (It's not loose footed)

Any reason why I shouldn't put a ring on the tack cringle to move it higher? Cheaper than a new main :)
 
Flattening the mainsail

Yes that is bazare. I would imagine that the sail would be under tension from the bolt rope or slugs on the mast to the bolt rope or clew tension hence pulling the area normally with camber quite flat. Well it may be an improvement over the original full sail but yuckkk....
Of course you can fit a shackle from eyelet to tack attachment to try it. If you have a looses footed mainsail then the height won't make much difference (raise the boom slightly) but if you have a bolt rope in the boom it will apply tension on the bolt rope.
IMHO opinion the tack attach should be in just the right place to remove pull on the luff of the sail in the track above the tack and if you have a bolt rope to remove tension from the bolt rope. ie a straight line pull from outhaul and halyard to the tack attachment the slugs bolt rope etc just being there to stop the luff flapping away from the mast.

Now having applied lots of halyard tension and outhaul if the sail is still too baggy. Then you may be able to bend the mast. A middle forward bend will tend to pull the cloth out via the slugs or bolt rope so remove camber. This is a standard adjustment on fractional rigs but not so easy with mast head rig. Use the backstay and inner forestay on mast head to get a bend perhaps equivalent to the fore and aft dimension of the mast extrusion. You far more bend on a fractional rig.
You can try a cunningham tensioner where a tackle is put onto the eyelet just above the tack to pull the luff really tight and at the same time tend to fold up the first few inches of the foot.
Some sails have a flattening reef which is an equivalent eyelet at the clew which takes a few inches of leach down and so folds up the baggiest part of the sail without loss of much area.
Or lastly put ina reef if there is plenty of wind.
If our sail doesn't have a cunningham eye flattening reef or reefing of any sort you should take it to a sailmaker (or do it yourself). However if you take it to a sailmaker it might be just as easy to get him to remove some of the fullness. Take him photos of your problem. good luck olewill
 
I had a baggy main on my Foxcub when I bought her. No amount of fiddling would do anything with it so I had to buy a new sail.

Is yours as bad as this?

mainbagginess.jpg


The new sail worked well

Slippy_2crop.jpg
 
Ruffles said:
Our old main is due for renewal as it's pretty baggy and impossible to flatten. However when we first used the thing at the beginning of the season it seemed to have magically improved - until I noticed I hadn't attached it at the tack! (It's not loose footed)

Any reason why I shouldn't put a ring on the tack cringle to move it higher? Cheaper than a new main :)
Click to expand...

No reason at all IMO - correct sail shape is the goal after all. Just be aware that you may put additional strain on the bolt rope at the bottom, where you're pulling against it rather than the tack cringle.. If its a choice of that or a new main then try it and see how you get on. Have another look - you might find its actually moving aft more than up...
A long shackle can be a good way of moving it a little bit. :D
 
Experiment with a bit of line from the cringle to the boom. Then you can optimise effect.
In fact I would just use a bit of line. Full Stop.
 
Actually, come to think of it, I tightened the back stay by a good 15 mm when I re-assembled the roller furling. Not sure that would have that much affect on the main with a mast head rig though.

Most embarrassing to have have sailed an entire day without noticing the tack. A good heave on the halyard would presumably have ripped the main.
 
I think the OP has just re-invented the flattening reef, using the boltrope as the 'new' tack !

I had a sail with that years ago, really an excuse for a poor cut.

I'm with Lakesailor, it's a sailing boat so treat her to a decent sail; and Lakesailor, no I've never seen anything that bad, I think I feel sick !
 
Seajet said:
I think the OP has just re-invented the flattening reef, using the boltrope as the 'new' tack !

I had a sail with that years ago, really an excuse for a poor cut.

I'm with Lakesailor, it's a sailing boat so treat her to a decent sail; and Lakesailor, no I've never seen anything that bad, I think I feel sick !
Click to expand...

I think you are being a bit unfair to the flattening reef, the dacron cruising main on our old Sigma 38 had such a cringle just a foot up, it made a remarkable difference to sail shape and was effective from about 16 to 22 knots, and very fast to pull in and out as you went on or off the wind, it also had the incidental advantage of lifting the Sigmas widow maker boom just above head height, so was often used running dead down wind in strong winds.
Shame they went out of fashion with the advent of loose footed sails.
 
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