Loose footed

Me too Smiffy! New Kemp powermain on order, loose footed as their sail designer recommended.

Almost all new boats seem to have loose footed mains (someone will quickly correct if that's wrong). I don't see why you couldn't have a flattener, if you wanted. I don't need to as I've no "black band" to worry about, and plenty of travel on the outhaul.
 
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Disadvantages? ....
If you're really serious about sail shape, the foot of the sail in a track always gives me a good indication of how well tensioned the outhaul is whereas with a loose footed main, it's sometimes hard to tell. ...

[/ QUOTE ]Trying to understand that point. Are you comparing to a lens footed sail? Where the lens panel shows the full depth of the sail with the outhaul fully slack, then scrunches up into horizontal folds as you pull the outhaul on hard.
 
Hello Tony Smiffy /forums/images/graemlins/smile.gif Blimey, common as muck aint we? Perhaps we can compare notes later when we have got it all together? Anything that will give my old Nomad a bit of a kick up the arris, will be good! /forums/images/graemlins/grin.gif I also got one of Kemps super cruise gennies, so hopefully the combination of the two should improve things? If not, I will either shoot it or sell it! /forums/images/graemlins/grin.gif

Charlie Smith.
 
I took delivery of a loose-footed main this year, switching from non-lf. It seems the principal advantage is in light airs. With the old sail, easing the clew outhaul wouldn't have much effect short-term (would settle down longer term) due to friction of the bolt rope in the boom groove. That has gone, the sail responds directly to clew outhaul trimming. I am not sure I follow Omitako's reasoning, as it is the shape of the bottom third of the sail I am looking at, rather than something local to the foot.

Other than that, the MAJOR ADVANTAGE IS WHEN TAKING THE SAIL OFF!! I decided to take the main off and put it in my garage, nice and dry. I have done that before, but it was such a hassle. I got the sail down into the lazy jacks, went to the mast and lifted out all the mast slides, detached tack and clew cringles, unrove the reefing lines. There is the sail lying unattached to anything on the boom. Folded back the sailbag like a sock, and two of us bagged it within about 3 minutes! All nicely flaked ready for putting on again next year.

I had taken the main off ONCE before, with old sails, and the act of sliding it out of the boom groove means it gets very difficult for two old fogies like us to handle and get into a bag.
 
Re: Loose footed - Disadvantage

and if it's fully battened, or 3/4 battened?
 
Re: Loose footed - Disadvantage

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No end plate effect on the foil, spills more wind. Easily solved by having a soft lens foot sewn in.

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That is a misconception. The foot is cut convex (curves down between tack and clew) such that when the clew is eased to it's normal/light wind setting the foot of the sail lies along the top of the boom in just the same way as a shelf or lens foot. Once the clew is tensioned more the foot sits straight along the boom top just as with any sail be it normal foootrope or shelf/lens foot.

We had a North fully battened shelf/lens foot main which we replaced with a Crusader loosefooted one, also fully battened but tri-radial cut and in Hydranet, dacron interwoven with Spectra/Dyneema at 5mm intervals in both warp and weft. The Crusader sail is superb, easily adjusted, better made (the North one had cheap polypropylene bolt ropes for example) sets beautifully and is a whole lot faster.

The loose footed sail is not like an in-mast sail which sits well clear of the boom and then there is no end-plate effect, think of the loose footed sail as a more easily adjusted shelf/lens foot and you will be nearer the truth.

As others have said there are other advantages too like being able to put ties around the flaked sail especially in lazyjacks and remove it easily for bagging when required. The outhaul controls work without bolt rope friction in the lightest of airs and the effects are easily seen albeit only on the bottom 25% of the sail.
 
I simply make the point that a sail with a bolt rope on the foot (in a track or on slugs) pretty much limits the extent that the outhaul can be "hauled" whereas a loose footed sail maybe stretches with excessive tension and it's kind of hard to tell when the stretching starts. Over the longer term this may damage the sail?

I guess if you're into spectra and all those other exotic materials things are different.

The one thing I have that won't stretch to fancy exotics is my budget /forums/images/graemlins/smile.gif
 
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That's true. Our previous boat had a lens foot, and there were very clear limits to the outhaul travel - fully slack was limited by the sail cut, and fully tensioned limited by the bolt-rope.

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But the outhaul limit is set only by the straight line distance between tack and clew. In any case you are only considering the theory of the full sail, once a slab reef is pulled in there is no shelf/lens foot yet the load on the cloth in wind strengths requiring a reef is much higher. The SLACK position of a loosefooted sail is different because let it off too far and the boom will drop where with a bolt rope it would a) not slide so easily back towards the mast, it would bunch up b) there might be some some lift to the boom then from the bolt rope.

You don't need exotic materials for this cut at all, at least no more than would be needed for a shelf foot or a straight bolt rope sail. In our case we DO have Spectra interwoven Dacron but that is because on our boat the sail loadings are high and standard material would stretch out of shape too much. However that is a function of the boat size and that we have a powerful cruiser/racer with a tall rig and large sail areas, nothing to do with having a loose footed mainsail.
 
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