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post #26 of Old 09-09-2012
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Re: In-mast furling

Originally Posted by davidpm View Post
What is the process to convert an in-mast furling system to a standard slab reefing system?

I have heard that the big charter companies are moving away from the in mast fullers? Is that true?

What is your experience with the in-mast systems and in conversions.
I suspect the conversion requires changing the mast. Sounds cost prohibitive. I suspect there might be a few workarounds, like the batt carr or something similar, but why?

I have years of experience with both. I am a fan of In mast. I can single much easier and my main often gets more use than my jib. I can reef at night without going forward (a huge plus) and pretty much stay in the safety of my cockpit.

As far as people having jams, what I typically see is that they are doing it wrong. Look at this picture:

Note the location and height of the clew and how high it is above the boom. The sail does not go horizontally into the mast, but the clew goes up at an angle. The issue becomes when people haul down hard on the boom vang or the main sheets and begin to crank in the sail. What happens is you stretch the leech and start to crinkle the sail. You cannot reef the main this way. You will get crinkles in it and probably a jam. You have to ease off the tension on the mainsheet and boom vang to allow the sail to travel "up" as it goes in.

Typical slab reefing you have the boom "horizontal" to the water, drop your halyard slowly while pulling in a jiffy reef line. Right (simplified, of course)? You keep your mainsheet taunt and your vang taunt. You crank down on that JR and probably go to the boom to secure the leftover sail.

Typical Inmast reefing, you ease off the vang and maybe the mainsheet while slowly letting out the outhaul and pulling in the reefing line. You have to let that boom travel up some to allow the clew to move up some as it goes into the slot.

So the problem, again, is you get a Slab reefer dropping in a reef like he might on a traditional slab reef main and the tension on the boom-to-clew causes a wrinkle in the sail and bamo! You got a jam.

For the record, we almost always reef by hand in normal conditions. We do not reef in via the winch and certainly never the electric winch. You cannot feel a hang if you do. If you are having to winch it in, head up to take some pressure off or make sure your boom and main sheets are taking the tension off the clew as it goes in. Also, you will see by the way the sail come out, one point of sail is better to reef than the other. At one point of sail, the main is resting against part of the mast. On the other, it is probably open to the slot. The latter is the easier reef. Also, put some McLube on the outhaul track on your boom. Its amazing how well that stuff works. If none of this works for you, make sure as you reef you are looking up at that slot and watching for wrinkles going in.

I have thousands of miles on my inmast and not one hang. Not one! And this includes some pretty nasty seas and storms. Heck, even my 8 yo and 12 yo reef it in (with help).

If you do everything as I discussed it, all by hand, you will NEVER have a jam you cannot get out. In the event you ever screw something up and do, I always wondered if it wouldn't be better to ease the outhaul all the way out and wrap the main around the mast. Then, take a spare halyard (SPI maybe), and wrap it backwards (opposite of the way the sail was wrapped) down the mast. Of course, it would not be perfect, but I have always wondered if this wouldn't work?? No experience with this, just throught I might try it. I would certainly do that before going up a halyard and slicing down a very expensive piece of rigging. At that point, there is no going back.

The big negative to inmast, other than the potential to really screw up some running rigging, is the performance. I personally think the best system of all may be a in-boom? That would be my choice. I also heard that many of the major manufacturers like Catalina may charge extra for the old traditional mast. Inmast is standard. I suspect that is a function of cost-supply, but I cannot verify any of this, was only told it by someone on the dock.

As far as the charter companies companies coming off it, that is completely understandable. All you need is one half-drunk gorilla on the reefing line wrapped around the electric winch, one good jam, and you get a bunch of PO'd customers and a really screwed up boat. Theres a lot less potential to screw up a trad sail plan... but that does not make it better.

My opinions.


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