Profurl In-Boom Mainsal Furling

BrianH

BrianH

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www.brianhenry.byethost18.com
Needing a new mainsail and being well 'over-the-hill' so finding leaping around furling my ancient slab reefing system a bit daunting in a serious blow, I am trembling on the brink of ordering a complete sail and in-boom furling system, shown here.

My local, favourite sailmaker is the Profurl agent and has quoted for the package at a relatively competitive price. Has anyone any constructive comments, either for or against, the system?

Thanks in advance.
 
I can't afford it, therefore it's a bad thing /forums/images/graemlins/smile.gif

Seriously, I would not want it on the grounds of its cost [there are more useful things I could spend the money on], and the fact that it is something else to go wrong that I might not be able to fix at sea. But that's just my personal opinion - based on one long voyage on a boat equipped with it.

I don't know how old you are but I am in my late sixties and have slab-reefing. I go on deck to reef, and tie off the reef points, but I found it much less of a chore if I heave-to first.
 
No experience of that system, but in boom furling is far more sensible than in-mast furling, which I have.

Keeps the weight down, smaller section mast compared to inmast furling hence far less windage, allows you to use a "proper" mainlasil, eg. battens etc. If it gets jammed, just dump the halyard!!

There are a few "off the shelf" varients. Doyle also do one.

To be honest on a small yacht something around 36 feet ish, I'm not sure if it would be of any benefit against a properly set up slab reefing system with lazy jacks. Both have a halyard, so it comes down to the reefing system against the method of controlling the boom rurler. Now if you had a hydraulic boom furler....!
 
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... it is something else to go wrong that I might not be able to fix at sea.

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The advantage of the in-boom reefing is exactly that, even if something did go wrong with the mechanism, the sail can still be dropped and secured.

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But that's just my personal opinion - based on one long voyage on a boat equipped with it.

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This subjective opinion is exactly what I'm looking for - care to elaborate just what made you reach it?

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I don't know how old you are but I am in my late sixties and have slab-reefing.

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Well, I'm well into my 70s and sail single handed in an area where unpredictable and violent weather can brew up in minutes (Northern Adriatic). I've had some struggles reefing this year that has concentrated my mind wonderfully on alleviating such incidents.

Then there was a time only a week ago that I was beating up to a narrow entrance, just being able to lay my course in a channel, in a wind that had started gusting over 30 knots and causing me to screw up into it no matter how much I tried to spill wind and apply full helm. There was no way I could reef the mainsail without falling off to leeward, out of the channel and the comparison of that with the ease of the roller reefing headsail made me think. And, by the way, my engine had failed to start!

Thanks for your thoughts.
 
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To be honest on a small yacht something around 36 feet ish, I'm not sure if it would be of any benefit against a properly set up slab reefing system with lazy jacks.

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I only have 31 feet and already have lazy jacks and bag. Dropping the main entirely is no problem, it's reefing with getting the cringle and outhaul properly in place that seems the difficulty.

But it is interesting you think in-boom would be better than your in-mast system. Theoretically, it seems to have advantages but I wondered how it really has developed, given the shorter period to improve the principle where in-mast seems to be on so many new boats and has, no doubt, become perfected over the years.
 
Sorry. I misread your post. /forums/images/graemlins/blush.gif

My comments were directed at "in-mast" reefing. I have no experience of "in-boom" reefing.

I will stay behind tonight and write out 50 times "Read post before replying".
 
I'm not a fan of inmast:

If it goes wrong it could go seriously wrong
Unless you spend extra on a vertically battened main, generally you end up with a flattish main with no roach
It puts weight in the mast, especially high up the mast, which increases pitching and heel moments.

So, I'd go for in-boom if it were a decision I needed to take. As for in-boom not being perfected, maybe not, but if it goes wrong, you've still got the option of reefing or dropping the sail conventionally.
 
This is "second hand" and I didn't go into it deeply. But a friend had in boom fitted (at quite some cost) on a Moody 376. I later heard from him that he removed it as it was a heavy haul which he found too much as there was just the two of them.
 
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I later heard from him that he removed it as it was a heavy haul which he found too much as there was just the two of them.

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Now that's interesting. By "heavy haul" does he mean to haul in the reef line? If so, we should know the make (different manufacturers use different mechanisms), mainsail area, the reef line lead (mast base or back to cockpit).

Recent developments has improved the principle a lot, with open booms to give no friction of the sail as it rolls and, at the same time, access to the reefing line and sail luff.
 
The problem was that raising the sail was hard work. I would say that this was about six or seven years ago. If the boom systems have improved in that time, then my information will be out of date. If that's the case, sorry for misleading you. I don't know the make and see him infrequently. But I will ask him when I do.
 
No problem, I appreciate any dialogue that makes me think about potential problems.

Theoretically, raising sail should be similar to raising a furling headsail - the luff runs in a narrow groove, the body of which rotates with the sail angle. It may well have a high friction and it is something I hadn't considered - thanks for raising it.
 
As a retrofit there is no contest, in boom is the way to go unless you are going to replace the mast. Retrofit in mast are not as good as masts designed for the job and add considerable weight.

I don't have direct experience of in boom but published reports are generally positive. I have in mast from Selden, and I think the negatives, apart from the potential jam which I have not yet experienced are overstated. I like the easy reefing and the flexibilitty of being able to adjust sail shape with the outhaul. The original sails were cut too full, but my new main is flatter and much better.

That does not really help you unless you are prepared to bite the bullet and get a new rig. You can overcome the potential loss of sail area by having a longer boom and therefore bigger sail, but less the roach.

Hope this helps.
 
We've had our boat, with in-mast for 4 years and only had one problem. Provided you take your time it is fine, but when we ripped a seam it was a bit difficult getting it fully furled. Fortunately it came out again no problems.

Whilst in-mast has I think probably been around longer, in-boom has been used a fair amount on the bigger yachts. At the end of the day it is the same principal, except if you need to drop the sail you can and there is far far less weight up top. Unless your boat has been designed with in-mast from the naval archs drawing board it will affect performance and stability, negatively for both. In-boom won’t do this, well only very marginally.

It is a far more logical and sensible arrangement from all perspectives than in-mast.
 
Its interetsing to note that when Tom Cunliffe loked at this he suprisingly found the in mast to be the best and the in-boom to be the worst.

IN my experience of over 10,000 miles on several in-masts including a trans-atlantic , in mast is actually better then in boom, because all in booms requires tight control over the vertical position of the boom when furling and this can be difficult, lots of in-boom users I talked to seem to mention the difficulty in getting a clean furl. Many had the luff walk into the boom end etc.

Modern in-mast is as reliable as headsail furling systems , just avoid vertical battens like the plague. As to stability and sail area, these are issues for retrospective additons rather then boats designed with the feature from the beginning.

I really think that the "preceived" drawbacks of in-mast are just that
 
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Its interetsing to note that when Tom Cunliffe loked at this he suprisingly found the in mast to be the best and the in-boom to be the worst.

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Interesting, can you cite where and why?

I didn't intend this to become a 'which is best' contest - I just think my own options are limited by my mast and that, as Tranona pointed out, for a retrofit the in-mast has drawbacks, which a properly designed mast catering for furling has not. In-boom makes sense but I did want to trawl for some practical experiences, such as:

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... all in booms requires tight control over the vertical position of the boom when furling and this can be difficult, lots of in-boom users I talked to seem to mention the difficulty in getting a clean furl. Many had the luff walk into the boom end etc.

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which is exactly what I was worried about.

However, the Profurl system uses a very rigid boom vang to keep the angle at 87 degrees to the mast, thus ensuring the correct tension at the right points on the sail to ensure flat, precise furling. This does require that the mainsail is tailored to the system.

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I really think that the "preceived" drawbacks of in-mast are just that

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I agree with you and it was my first choice - it was only when my attention was drawn to the latest in-boom alternative that I have been seduced towards that.

Thank you all for some very interesting food for thought.
 
I had a Profurl In-Boom Mainsail Furling on my last boat and found it excellent. The boom is beautifully made and well engineered but, as it has to stow the mainsail inside itself, it is bigger than a normal slab reefing boom. And because of its size it is supplied with a Walder boom brake which works well, an accidental gibe could inflict serious damage to a human head !

The only problem I had was that the main halyard and the furling line passed through 4 halyard organisers which imposed considerable frictional losses that made it hard work to hoist, reef and furl. With a more normal setup it would be much easier.

A good piece of kit.
 
Profurl is a good system. I think the LeisureFurl is a better asystem, but more expensive.

Profurl would probably be my choice on a cost/benefit analysis.

In - boom system is good unless you have a low boom height, as it increases the mass, that could impact your skull.
 
Thank you for that information - at last someone who has had the system and can recommend it - invaluable.

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The only problem I had was that the main halyard and the furling line passed through 4 halyard organisers which imposed considerable frictional losses that made it hard work to hoist, reef and furl.


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I presume this was just your own configuration - that does sound excessive. I do plan to lead back to the cockpit but through only two organisers after exiting the mast (halyard) and a block on the mast base (reefing line).
 
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In - boom system is good unless you have a low boom height, as it increases the mass, that could impact your skull.

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My present boom height is high - to clear the pilot house (HR94), which it does with about half a metre to spare - but I am now forewarned not to be tempted to gain sail area by lowering it with the new system, which I was highly tempted to do.
 
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I only have 31 feet and already have lazy jacks and bag. Dropping the main entirely is no problem, it's reefing with getting the cringle and outhaul properly in place that seems the difficulty.

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This may be off at a tangent to your original query, but have you considered keeping slab reefing but rearranging the system so that everything works from the cockpit? More rope to cope with, but less jumping around and a more stable working platform.
 
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