Loose footed main vs attached mainsail

lancelot9898 · #1 (**permalink**) 06-02-2011

I've listed some questions that I have about replacing my 25 year old North sail which is attached to the boom with a new loose footed main.

1. Most everything that I've read seems to prefer loose footed over the attached mainsail for better sailing performance on all points of sail. Does anyone here have a different opinion?

2. I assume the dimensions of both sails would be the same(luff, leech and foot)?

3. The new sail will be made with "over the top" leech line so that the line can be controlled at the tack rather than the clew. I assume that provisions can be made for controlling that line when reefed.# Is there a need for a foot line? (Loose footed staysail does not have one.)

4. The attached old sail has a small "shelf foot". Does a loose footed sail have one and if so how do you specify the size?

5. Is a cunningham cringle needed for a loose footed sail?

6. Someone suggested putting a slug near the clew and attaching to the boom. Not sure if this is needed and may defeat the advantages of a loose footed sail. Again the loose footed staysail does not have this.

7. Not going with full length battens due to increase friction in hoisting and dousing sail, however, maybe the top batten can be full length. Any comments pro or con about batten lenght? Charlie, what's your experience with performance with the 2+2 battens?

8. The Challenge marblehead weave seems to be specified for low aspect sails. (less than 2.5) Is the aspect ratio calculated by luff devided by foot? If so, then something other than marblehead is needed and there is a whole list of Challenge sailcloth available. Comments on what is best? I went with High Aspect 8.62 on the new staysail that is on order.

9. The slugs in the mast are for the most part made of plastic while the reef points and head use metal slugs. Are there any differences in the type of plastics available (pro and con)?

Thanks for any and all comments!

The boat is a Tayana 37 with a yatch spar mast(New Zealand)

# (Rich supplied the following info) The leech line runs up normally to the headboard but instead of being attached/sewn near the headboard it continues to a 'cheekblock' mounted ON the headboard then continues in a small sleeve down along the luff tape .... For evey 'cleat' (each reef position) at the leech there is also a cleat at the luff, and the leech cord is exposed (not in the luff sleeve at each luff reef cringle. ....

Not sure how the cam cleats work on reefing. Seems like you have to set the line on the leech at each reef point....and once the line is set it seems like when you shake the reef out the line has to be removed from that particular cam cleat on the leech??

Jeff_H · #2 (**permalink**) 06-02-2011

1. Most everything that I've read seems to prefer loose footed over the attached mainsail for better sailing performance on all points of sail. Does anyone here have a different opinion?
There should not be a noticable performance difference but loose foot mains are generally considered to offer slightly better performance.

2. I assume the dimensions of both sails would be the same(luff, leech and foot)?

Yes, but a loose foot main will have roach in the foot.

3. The new sail will be made with "over the top" leech line so that the line can be controlled at the tack rather than the clew. I assume that provisions can be made for controlling that line when reefed.# Is there a need for a foot line? (Loose footed staysail does not have one.)
Over the top leech lines are the way to go. It allows the leech line to be adjusted without having to pull the boom in first, so the sail is adjusted in its actual flying position. In other words, in real time rather than trial and error. There is a clam cleat at each reef but they are angled so that they automatically release when you hoist the sail again.

4. The attached old sail has a small "shelf foot". Does a loose footed sail have one and if so how do you specify the size?
There is no shelf on a loosefoot main.

5. Is a cunningham cringle needed for a loose footed sail?
Yes, but you usually do not need a flattening reef.

6. Someone suggested putting a slug near the clew and attaching to the boom. Not sure if this is needed and may defeat the advantages of a loose footed sail. Again the loose footed staysail does not have this.

You will either need a slug at the clew or else a strap to hold the clew close to the boom. Sailmakers sometimes suggest a slug at the tack as well but that depends on the geometry of the attachment for your tack. Normally there is a shackle welded to the gooseneck that precisely sets the position of the tack. But some set-ups (like I have on my boat) do not accurately vertically and/or horizontally fix the position the tack and so sailmakers may wish to do a work around.

7. Not going with full length battens due to increase friction in hoisting and dousing sail, however, maybe the top batten can be full length. Any comments pro or con about batten lenght? Charlie, what's your experience with performance with the 2+2 battens?
I am a fan of 2 x 2 on smaller boats (under 30-32 feet) but prefer full length battens on bigger boats. I do not have any special tracks or slugs for my battens and they generally do not hang up. The key to that is that the battens need to be horizontal rather than tilted up as they would be if they were partial length. I have mixed feelings about full length battens for distance cruising. There is no way to carry spare full length battens on most boats. I would be tempted to use full length battens for distance cruising because of the greater sail life, but add partial length batten pockets and carry battens for those, in case of an emergency.

8. The Challenge marblehead weave seems to be specified for low aspect sails. (less than 2.5) Is the aspect ratio calculated by luff devided by foot? If so, then something other than marblehead is needed and there is a whole list of Challenge sailcloth available. Comments on what is best? I went with High Aspect 8.62 on the new staysail that is on order.

9. The slugs in the mast are for the most part made of plastic while the reef points and head use metal slugs. Are there any differences in the type of plastics available (pro and con)?
Not really.

ccriders · #3 (**permalink**) 06-02-2011

The slug at the clew will keep the clew in contact with the boom when you slack the outhaul in light winds, expecially if there is a long distance to the outhaul turning block. It also helps control the sail while taking it off the mast.
Check carefully that the new foot will have sufficient room on the boom to travel to meet your adjusment requirements. You will probably adjust your clew outhaul more frequently and over a greater range with a loose footed main.
If your boom is fixed to the mast then you need a cunningham.
Just having a new sail will be pretty amazing to you.
John

chef2sail · #4 (**permalink**) 06-02-2011

We just purchase our first loose footed main from Quantum after years of the boltrope in the boom with a shelf kind of main.

Jeff H comments are right on. I like the 4 full battens already as it has helped maintain the sail shape in various degrees of wind. It also prevents the extra small amount off luffing which wears out a sail more quickly.

I like the advantage of adjusting the outhaul slighly when on different p[oints of sail and have notice a small uincrease in speed. Not sure how much of that is my tinkering as opposed to the new vrs old streched sail.

It is so much easier to reef in terms of bundling the extra sail with sail ties as you dont have to go around the boom now.

All in all I have not seen any real perceptable differece

I did have to get used to seeing daylight bwtween the boom and the sail.

Faster · #5 (**permalink**) 06-02-2011

On the last sport boat we owned there wasn't even a tack cringle/attachment at the gooseneck.. the sail hoisted to the band with no tension and luff tension was entirely applied with the cunningham. This on a 24 foot frac, no halyard winch and a 6:1 cunningham purchase.

A clew strap is a good alternative way to attach the clew as long as the boom section is clear of protrusions like blocks and padeyes. - No slug required.

j34035 · #6 (**permalink**) 06-02-2011

You cant use the foot of a loose footed main as a hammock when under way (watch out for jibes) like you can a mainsail with a shelf. That is the only disadvantage I have found. My last 2 have been loose and I feel the shape is much easier to control. Jeff and others have answered your quesitons quite well.
DD

turbulicity · #7 (**permalink**) 06-02-2011

Good discussion here. I have an in-mast furling main and it is naturally loose footed. I was wondering if it was just something else (like battens) you are giving up for the sake of furling. Nice to hear that it is not a bad thing in terms of performance. One thing I would add is that it improves visibility.

lancelot9898 · #8 (**permalink**) 06-03-2011

Thanks for all the great comments. I think it was Jeff that mentioned the roach foot. How do you specify the amount of roach needed in the foot?( ie a certain % of the foot length?)

On the Challenge sailcloth question there is an application chart on their website that shows the 8.77(Marblehead weave) for mainsail application on a 37-41 foot sailboat with an aspect ration between 2:1 -3.1. My mainsail's ratio is 2.8 so apparently I can go with the marblehead weave.