Boom Furling

[irwinsailor]

Does anyone gere have boom furling on thier boat? How do you like it and is it worth the cost?

[Jeff H]

My Father had a Hood in boom furling system on his Brewer 12.8 (42 foot cutter) when he bought it. He found that it was unreliable and cumbersome, especially when used in a breeze. He also felt that the resulting sail shape was not very good with the partially furled sail. He converted back to a conventional boom with slab reefing and a Dutchman system, and seems to be quite happy with it. Dad is in his late 70's but is quite fit. He does have electric winches for the jib sheets and has the boat set up so that he can raise the main using one of these electric winches.

Jeff

[Talbot]

Biggest problem with both in-boom, or in/behind mast reefing is that the sail material will be a lot lighter than conventional slab reefed mainsail. Thus you will need to reef earlier. On the otherhand they will tend to be better in lighter airs (certainly my behind mast sail (with full vertical battens) is much more efficient than the previous fully battened slab reefed main in light breezes. I changed to make it a lot easier to operate when short handed and have not regretted my decision.

[Jeff H]

It would be very unusual for a roller furling sail, especially a behind the mast furler, of equal weight and age to be as efficient as a normal slab reefed sail. Sails made for roller furling generally need to be cut flatter to prevent jambing on the furler, and tend to have generally less efficent flying shapes at the low end and high end of the wind range.

Jeff

[Talbot]

Jeff H once whispered in the wind:
It would be very unusual for a roller furling sail, especially a behind the mast furler, of equal weight and age to be as efficient as a normal slab reefed sail. Sails made for roller furling generally need to be cut flatter to prevent jambing on the furler, and tend to have generally less efficent flying shapes at the low end and high end of the wind range.
Jeff

Of course I dont disagree with you on the sail shape, however, unless you have had your main cut with a step, it is very difficult to get a good shape into a normal slab reefed sail in light wind conditions, whereas a loose footed sail with full vertical battens can be given a nice shape. furthermore, their lighter construction is of benefit in the lighter airs. All IMHO, and purely from the results of my own boat.

[Jeff H]

"it is very difficult to get a good shape into a normal slab reefed sail in light wind conditions, whereas a loose footed sail with full vertical battens can be given a nice shape. furthermore, their lighter construction is of benefit in the lighter airs. "

I think that you have gotten this very backwards. Given two sails of equal weight and age, it is much easier to get proper shape into a slab reefed sail vs a roller furled sail since the sail made for slab reefing can be and generally is cut with a better light air shape than that of a furling sail which is why slabbed reefed mainsails are used for virtually all modern racing mainsails.

For a given stretch and sail lifespan furling sails generally need to be built heavier (not lighter) than non-furling sails because the furling sail must be designed to resist the very high point loads that are developed in the partially furled position. That said you are often limited in the weight of sail cloth that can used on a furling sail where as you are you have the option of using heavier fabrics on a non-furling sail if you are sailing in a predominantly windy venue.

Loose footed sails only offer better performance in the situation where the foot is extended down below the boom as is the case in modern performance sails. They do not offer better performance when they are used with vertical furlers because they lose both the overlap and the end plate effect of the shelf that is typical on a perfoemance oriented bolt roped foot mainsail.

Horizontal battens are way more efficient than vertical battens, especially in light air, which is why horizontal battens are used on virtually all racing mainsails.

It sounds like you replaced an older, heavier weight mainsail with a new lighter weight sail and noticed better light air performance. That is not surprising but it has nothing to do with furler and everything to do with the fact that it is a new and lighter weight sail. If you did not have the behind the mast furling system, you would actually get even better performance out of the new mainsail of a similar weight material, (especially in light air where the non-furling sail would benefit from not have the added weight of the sunshield material on the leech) and the non-furling sail would have a much longer lifespan. Using sails in the partially furled condition greatly shortens the life of the sail.

Respectfully,
Jeff

[harryrezz]

We've looked into all the mainsail handling options and agree with Jeff's dad - we're going with a Dutchman system - including the behind-the-mast track and new slides. I simply don't trust roller furlers on the main - too much chance of them fouling, especially when the wind pipes up - and too hard on the sail itself. We looked into a Stack-Pak type system, too - but they don't do as nice a job of flaking the sail as does the Dutchman system.

[GeorgesCutter]

Very valuable mains'l observations.
Thanks all!

[capngeo]

I have one on my CAL28. My biggest gripe is that you need to be extra careful when dropping sail; no wind loading and maintain tension on the halyard, or it will not roll tight enough to completely stow in the boom. Certainly not a fast operation. In fact I find myself reefing and stowing a lot earlier than I did with lazy jacks, just to avoid having a jam in a tight spot. That said, I do like the "neatness" and no need to leave the cockpit when reefing.

[SimonV]

Would I keep a boom furler if it came with a new boat, Yes. Would I swap out my slab reefing for an expensive boom furler, No. I have delivered a number of boats with boom furlers and found them all servicable if not a little finiky. When delivering a 47 footer with the owners, they snapped the continuous furling line that was operated by a large electric drivein drum winch when the operator forgot to completly release ther cam cleat. One thing with a boom furler no matter what you can always drop the main.

[Juniper]

I've wondered about a boom furling not reefing set up, you just use the rotating boom to store the main on and still have an out haul and reef hooks, that way the extra sail is just rolled up, it wouldn't be infinantly adjustable just more convenent then flaking and tieing.
I currently have an in mast.

[barnakiel]

We do not have it but I used this system on a couple of boats. I did not like it, much as it is practical on bigger boats.

My preference is always slabs. However, on a big boat with wee crew slabs can be impractical.

b.