trapezeartist
Well-Known Member
I've seen many references to roller-furling genoas with a "foam luff". Apparently this improves the sail shape when the sail is well furled. How does that work? What does the foam luff consit of? Any pictures?
Foam Luff
- Thread starter trapezeartist
- Start date
webcraft
Well-Known Member
Yes
.
It's a cylinder of foam (well actually not a perfect cylinder, but you get the idea) sewn into the luff of the genoa.
When you furl a non-foam-luffed genoa the shape of the sail deteriorates as the roll takes up the built in 'belly' of the sail. The foam sausage minimises this effect.
Makes a big difference if you want to go to windward sensibly with half the genny rolled away (IMHO) and well worth the extra £100 or whatever.
- W
.
It's a cylinder of foam (well actually not a perfect cylinder, but you get the idea) sewn into the luff of the genoa.
When you furl a non-foam-luffed genoa the shape of the sail deteriorates as the roll takes up the built in 'belly' of the sail. The foam sausage minimises this effect.
Makes a big difference if you want to go to windward sensibly with half the genny rolled away (IMHO) and well worth the extra £100 or whatever.
- W
srm
Well-Known Member
On my catamaran its a flat pad sandwiched between an extra piece of sailcloth and widest at the middle of the sail tapering out to nothing at head and foot.
Its the only one I have come across and the sail rolls up really well and keeps a good shape even when well reefed.
Am thinking of adding the same to my new boat's yankee jib if I can find a supplier for the foam.
Its the only one I have come across and the sail rolls up really well and keeps a good shape even when well reefed.
Am thinking of adding the same to my new boat's yankee jib if I can find a supplier for the foam.
purplerobbie
Well-Known Member
When i bought my new sails i was told not to have a foam luff fitted. His theory is a new sail will hold its shape when rolled and by the time it has stretched and needs a foam luff the foam in it will be worn out.
Save your money and have it fitted when it needs it
I thought this made quite a lot of sense and was a refreshing change from people trying to sell thing that are not needed.
Rob
Save your money and have it fitted when it needs it
I thought this made quite a lot of sense and was a refreshing change from people trying to sell thing that are not needed.
Rob
jason -and the arguenauts
Well-Known Member
Thats dodgy advice since all sails when brand new have belly cut into them. If they didnt, they wouldnt work as an aerofoil. And if they have some belly, then as the sail is rolled up, this gets pushed more and more to the leach of the sail and you end up with a sail thats luffind at top and bottom and over full in the middle.
The problem is that as the sail ages and sags even more in the middle, the foam gets squashed and becomes less effective. So it needs replacing and increasing.
personally I'm not conviced about foam luffs cos the big bulk of rolled up sail messes up the genoa when it rolled anyway. Maybe better to save the dosh and put it towards a 100% yankee for use when the wind gets up.
The problem is that as the sail ages and sags even more in the middle, the foam gets squashed and becomes less effective. So it needs replacing and increasing.
personally I'm not conviced about foam luffs cos the big bulk of rolled up sail messes up the genoa when it rolled anyway. Maybe better to save the dosh and put it towards a 100% yankee for use when the wind gets up.
Sans Bateau
Well-Known Member
Your first two paragraphs are spot on, your third, which is as you say, an opinion, may be technically correct, but the whole point of a rolling furler is so you can reduce sail without a sail change. A foam luff is not perfect, but an acceptable compromise.
Robin
Well-Known Member
We have a Furlex system with a 'lag' device on the bottom so that it allows a part roll in the middle before the bottom rolls. We also have a foam luff which improves the sail very well when rolled. Our foam luff is actually made up of closed cell foam tubing as used for pipe lagging, it starts as one then progresses to two then 3 towards the middle of the luff. This foam luff method doesn't hold damp and create mildew like using a flat material would, nor does it compress and lose effectiveness over time.
dunedin
Well-Known Member
Even when brand new, a sail will tend to furl badly as the foot and leach are typically thicker due to doubling over of the material. Hence the edges roll thicker than the centre bit. If you then sheet in tight to go to windward the centre bit tightens up and creates a bag at the luff.
Hence the foam luff tends to be tapered so that as the sail furls and the extra thickness of the cloth starts to roll up it keeps a good shape. Doesn't need to be foam. One sailmaker used a three strand rope, which was tapered by thining then removing strands so down to one strand at the edges.
Essential, unless a small jib
Hence the foam luff tends to be tapered so that as the sail furls and the extra thickness of the cloth starts to roll up it keeps a good shape. Doesn't need to be foam. One sailmaker used a three strand rope, which was tapered by thining then removing strands so down to one strand at the edges.
Essential, unless a small jib
DaveS
Well-Known Member
Foam luff
I would agree with other supporters of a tapered foam luff. The taper bit is important. Mine is made of different lengthed strips of foam, and a couple of years ago one of the smaller bits became detached and slid down the sailcloth "tube" towards the tack. This made a huge difference to the reefed (reeved?) sail shape and, since I couldn't find a DIY way to retrieve it, I had to pay a sailmaker to sort things out. I considered this money well spent.
I would agree with other supporters of a tapered foam luff. The taper bit is important. Mine is made of different lengthed strips of foam, and a couple of years ago one of the smaller bits became detached and slid down the sailcloth "tube" towards the tack. This made a huge difference to the reefed (reeved?) sail shape and, since I couldn't find a DIY way to retrieve it, I had to pay a sailmaker to sort things out. I considered this money well spent.
michael_w
Well-Known Member
A rope padded luff is better. I doesn't get as crushed as a foam one. A small pocket is sewn just aft of the luff rope and filled with, you guessed it, rope.
To get a well setting sail the use of laminate sailcloth and no UV strip helps enomously. I've used this arrangement sucessfully on two sails and I've just ordered a third.
To get a well setting sail the use of laminate sailcloth and no UV strip helps enomously. I've used this arrangement sucessfully on two sails and I've just ordered a third.
trapezeartist
Well-Known Member
Thanks to all for the information.
PetiteFleur
Well-Known Member
My previous boat had a foam luff - made by Cranfields and it was far superior to my current genoa as it held it's shape really well until it was about half reefed. If I was buying a new sail I would have a foam luff, no UV strip but a pull up 'sock' to prevent UV degradation when furled.
wotayottie
Well-Known Member
is a foam luff better than a non foam luff roller furling genoa - yes. Is a foam luff roller furling genoa as efficient after furling as a smaller sail not furled - no it isnt. Like it or not, the bulk of sail materail wrapped round the foil does no good for performance at all.
uforea
Well-Known Member
flaming
Well-Known Member
Just as easy (and better for the sail) to drop and flake it after use.
michael_w
Well-Known Member
I tend to cover the sail with a sock as the rope padding makes it a bit bulky to flake easily and leaves no room in my fo'c'sle, which is like your cupboard under the stairs anyway!
In The Netherlands the use of sail socks is commonplace. The UV strip is a rarity over there. Perhaps they rate sail performance over convenience.
In The Netherlands the use of sail socks is commonplace. The UV strip is a rarity over there. Perhaps they rate sail performance over convenience.
Leighb
Well-Known Member
Perhaps in many areas there it is not so windy as in the UK?
Problem with socks can be a tendency to disintegrate if exposed to strong winds after a year or two.
dulcibella
Well-Known Member
My genoa has functioned well for over 12,000M without any detectable deterioration of the foam luff. It retains a decent sail shape almost down to storm jib size (though there are other reasons than shape for switching to a staysail or a storm jib in rising wind).
pagoda
Well-Known Member
Bulk of a padded Luff???
How well -or badly, do folks find they can fully furl a padded luff sail.
I've seen old sails not furl very tightly, old sails furled like pencils, some newer laminate /padded luff sails furling smoothly - but not very neatly...
How much do you sacrifice in furled neatness / bulk for the value of the padding and partly reefed foresails?
How well -or badly, do folks find they can fully furl a padded luff sail.
I've seen old sails not furl very tightly, old sails furled like pencils, some newer laminate /padded luff sails furling smoothly - but not very neatly...
How much do you sacrifice in furled neatness / bulk for the value of the padding and partly reefed foresails?
dunedin
Well-Known Member
Nothing. Furls perfectly well if done properly - and takes lsightly fewer turns to do so
