Why I don't have in mast furling.

Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
I'm not pushing any style. That's your call.
I will say my in mast furl system has worked in severe weather conditions. I can reef single handed in a full gale with infinite adjustment. When the storm stressed my boom car to where the bearings exploded I was still able to limp through furling and unfurling single handed over more than a thousand nm. In various wind conditions and seas including gale force.
The furling system allows me to have full control on the main at all times.
What do you do when a classic system unzips from the mast? And your sail is laid out on the water?
Agreed - anything can fail.
And also agree, over generalize anything and its no longer a valid discussion. I well understand your personal situation and would agree you have made the best choice for your program. But my basic premise stands - as a general solution for most blue water sailors, a traditional mainsail system is best, and offers lower risk of failure. Unzips from the mast? Most blue water mains are in track systems that have a failure rate 100x less than IMF.
 
Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
If I was younger and not disabled I would probably have opted for a classic rig. Better sail shape if for no other reason. Friends have a 52 foot Tyanna if that's how you spell it. They paid big money to convert from external mast furling to classic rig. Track and mast cars etc. They were sailing to Florida and their halyard jammed in the mast with the sail fully deployed. Had to swing into Gulfport at full sail for repairs.
Anything can happen at any time. It's what you make of it when it does happen that makes a sailor. Pass the Grog mate.
 
Jun 14, 2010
2,081
Robertson & Caine 2017 Leopard 40 CT
snip
For everyone I know with a IMF, the biggest reason they like them is not having to deal with zipping the lazy bag.
That's amazing to me, yet I do understand "lazy". More easily justified if you have a physical or age related handicap.
 
Jun 3, 2010
177
Hunter 27-3 Erie
Interesting discussion, let me toss in my 2 cents. When we got this Hunter it was our first boat with IMF and was one of the features we were looking for. I'll pass here reading off the whole wish list but it was based on new physical limitations put on the Admiral. When we took delivery we had what turned out to be very unrealistic expectations of the IMF system. It was not trouble free, easy to use, convenient or stress free. It was exactly opposite of all of those things and frankly, it pissed me off that we paid a premium price for the boat AND sold what I had hoped to be our "last boat"(another story for another discussion). What we ended up doing was 1. talk with other Hunter owners in our club and ask what we were doing wrong. 2. called the broker and former Hunter dealer and ask the same question. 3. dug through all the paperwork on the boat to find the spar manual for tips. What we found was that we had "assumed" the previous owner knew what he was doing setting up the rig, he did not. The other Hunter owners had IMF, but a different brand spar, so they were only a little help. The broker was more help and called his rigging guy. Finally, buried in the pile of papers in the canvas Hunter bag were two things, the manual for the spar which was totally useless and an addendum to the useless manual. The spar was originally designed to have a traditional rig, sail storage on the boom. We were told that so many people requested IMF the spar maker modified the current mast and added the foil and furling mechanism. HOWEVER, if you followed the instructions in the manual for tuning the mast, you were done, that IMF mechanism would never work........and it didn't.

The end of this story is that we found this to be a very sensitive rig. If the main halyard is too tight or too loose, it affects the mechanism. If the rig tuning is not to the specs in that addendum, there is too much pre-bend in the mast and the IMF will not work. If you don't put tension on the outhaul when furling the main, the sail wrap isn't tight enough and will jam in the mast. So, I bought a LOOS gauge, read the addendum carefully a couple of times, re-tensioned the standing rigging to suggested specs, played with the main halyard tension doing an inch tighter, an inch looser, etc. and ended up with an IMF system that now works ALL the time.
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
They were sailing to Florida and their halyard jammed in the mast with the sail fully deployed. Had to swing into Gulfport at full sail for repairs.
Anything can happen at any time. It's what you make of it when it does happen that makes a sailor.
A made sailor :) would have gone up the mast on the jib halyard and unshackled the main.

With a standard system, there is almost always an option to manage a sail malfunction. With an enclosed furler, you've added a possible barrier to management. Even with stories of reliability and robust nature, it's still a possible barrier that's been added.
However, with discussions like this one, a sailor can weigh his options. IE: if I were retired and only coastal cruising and day sailing, I would almost certainly opt for in-mast furling of a reliable reputation if it were on a prospective boat.
 
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Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
Like I said friends. Didn't mention seas. Lol.
I opt for blue water. If the sail system fails I have a 1000 nm cruising range thanks to the aux fuel tank I installed. Lol.
one can always wrap the sail around the mast using asy. Spin halyard or top lift etc.
enough of this crap.
back to my rum. LMFAO
 
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Oct 9, 2008
1,739
Bristol 29.9 Dana Point
Like I said friends. Didn't mention seas. Lol.
I opt for blue water. If the sail system fails I have a 1000 nm cruising range thanks to the aux fuel tank I installed.
one can always wrap the sail around the mast using asy. Spin halyard or top lift etc.
enough of this crap.
back to my rum. LMFAO
I'd like to see someone wrap a 37 footer's mainsail around a mast in gale force winds. It would be a fantastic learning experience for me the viewer.

If a standard sail fails, the skipper has a 1,000,000 nm range with bending on a spare sail.

About the rum:
"I'd say you've had enough."
-Slim Pickens

Or was that beans?

I say this with my hand on the Captain Morgan jug. Happy President's Day.
:)
 
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Dec 19, 2006
5,809
Hunter 36 Punta Gorda
I sailed my 2007 H-36 from Montauk NY to Fl almost all ocean with 4 of us as crew and 2 of the crew hated Hunters and Inmast but at the end of a 9 day trip they all said to me that they take back anything bad they had said loved the fact that no one had to go up to the mast to reef when the weather turned bad on those dark nights out on the ocean.
 
Jan 17, 2013
439
Catalina 310 St. Simons Island, GA
Larry, when i screw it up it means that I usually leave too much slack in the outhaul line when furling and I can tell it is bunching up. Then i pull it out and refurl until it is right. Happens once every 5 or 10 times. One key is to never winch in the sail because if you do that you could jam it because you lose the feel. I can feel when it is not right. Not sure if i would be able to furl it in by hand if my boat was 40 feet long? I also have a mainsail that is not the stock Catalina sail and it has excellent shape and 3 vertical battens. To each his own but i am very comfortable with IMF like I said.
 
Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
Take a line. tie to mast. Go around sail leach. Back around mast to elect winch in cockpit. Crank in line and tie off. Take whisker pole topping lift and start wrapping barber pole style.
Most classics have 2 reef points. IMF can reef down to napkin size.
My last post for this thread. The horse is now dead and the Flys are gathering. LOL
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
Take a line. tie to mast. Go around sail leach. Back around mast to elect winch in cockpit. Crank in line and tie off. Take whisker pole topping lift and start wrapping barber pole style.
Most classics have 2 reef points. IMF can reef down to napkin size.
My last post for this thread. The horse is now dead and the Flys are gathering. LOL
Why stop posting? Your remedy is one of the more valuable parts of this thread, including for standard rig sailors, especially those who are not able to go up the mast for various reasons.

I still invision the task as a difficult option for a jammed main in high winds, but it's still an option and possibly a great one in fair weather to enable entering a harbor or prepping for bad weather.

So if you don't mind a couple additional questions:
So on a loose foot, one would let go the topping lift and clew from the boom, leaving the boom on deck or supported by a rigid vang? Or maybe use a spin halyard for the barber pole instead of topping lift.
And what about a bolt rope attached foot?

I'm guessing the barber pole effect will only be doable below the lower shrouds, unless you're wrapping around the shrouds.

Or, and especially with an attached foot, one could use the topping lift to haul the aft of the boom and sail up together to be parallel to the mast, and even use the loose mainsheet and rope vang (if not rigid) as additional wrapping, using their existing attachments to the boom to secure it tight to the mast?
 

CarlN

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Jan 4, 2009
603
Ketch 55 Bristol, RI
As usual in these discussions, people who have never had mainsail furling see lots of problems

Those that have had it, would never own a boat without it

I've owned boats with a) in-mast furling b) boom furling, c) Doyle stackpack, d) "jiffy" reefing, e) gaff rig and f) roller boom with the mainsheet "claw". They all worked and all had some advantages.

But I'm definitely in the "would never own a boat without it" group.
 
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Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
Skipper.
Very good questions from a thinking sailor. I just mentioned the whisker pole topping lift as one of a few that can be used. I have a spinnaker halyard and the boom topping lift also to choose from. Use 2 and you can cross them. One one way the other the other way etc. I have a rigid vang to support the boom. I would not want to play with the boom though. Keep it lashed. A loose boom could damage shrouds or the mast. And could be dangerous to crew.
 
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MFD

.
Jun 23, 2016
93
Hunter 41DS Seattle
I am new to in mast furling, I have it, and it is appropriate for my use case of being mostly inland or near shore. I think I might be okay with it for blue water west coast canada to mexico but would never consider it for serious multi-year world wide cruising. There are simply too many things that can go wrong, and the worst thing anybody needs in a bad situation is the inability to drop a sail when it needs to happen.

For some of those - RTFM - I absolutely agree. For example, read the part about how to grease the upper bearings of the furling system as part of regular maintenance. Read your maintenance/repair manual on that part of things before you go offshore in a serious way?

On other topics - yes, from my experience halyard tension and sail handling appropriately is important.
 
Feb 11, 2017
9
I had IMF for 13 years and 30,000 NM. I have done deliveries with all other types of main systems. They all have issues. I've seen main slides hang up, bolt ropes binding, lazy jack systems failing at the wrong time, etc. I prefer IMF. The only difficulties I ever had were because the main was blown out and needed to be replaced. Even then, the only issue was bringing it out. It could hang up and needed the foot to be pulled. I had to endure that for about a month in the Bahamas because I didn't replace the main until I returned to the US. It was a minor inconvenience, and not consistent. This was on a Catalina 42 with a Charleston Spar...30,000 NM in 13 years, offshore and in the Chesapeake. You just can't have a baggy main. Sure there are some "rules" for furling and unfurling...head into the wind with a slight starboard tack for us, and release the vang a bit.

If someone is having a problem furling while in a gale, don't you think they waited too long? How many of you wait to reef until you're in a gale with whatever your chosen method of mainsail system?
 

capta

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Jun 4, 2009
4,766
Pearson 530 Admiralty Bay, Bequia SVG
I have yet to see an IMF system "screw up" all on it's own. It is ALWAYS operator error, unless something breaks. The most common problem I've seen is folks who try to force the system when it binds up a little. Always stop, reverse past the problem and then try again, slowly.
We sailed with a main that was so baggy that other boats sailing with us thought it was a hammock. And yet it never got hung up to the point we couldn't bring it in or out. As above, a lot of attention to what we were doing kept it functioning, even under extreme conditions. With the new main, it's like the sail is greased.
I can't for the life of me understand why anyone wouldn't want "infinite" reefing on their boom sails. No longer does the sailmaker determine how much sail I can have out for various conditions. I can choose exactly how much sail I want out, to the inch.
The other thing I absolutely LOVE about IMF is that I no longer need to head up into the wind, with my sail flogging away, to raise, lower or reef/unreef my main. Almost any point of sail will do!
So, for those shying away from IMF, for my 10 cents worth, go ahead and buy that boat. IMF has a learning curve. Of course you are going to have a few problems in the beginning, as you learn the system. But going slowly, paying attention to what you are doing and not forcing the system, will pay dividends in the long run. "It got stuck immediately" is just operator error and like everything else in life, new things take time learning. I doubt any of us hopped on a sailboat the very first time and sailed away, even w/o IMF.
 
Feb 11, 2017
108
Gulfstar 47 NC
I agree. Have used the the same Hood IMF for near 30 years. Routine maintenance. As with everything, there is a learning curve. It's always better to reduce sail early in a blow. Do not jam it, stop, back up and start over. I still love to push the button and stow the sail.
 
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Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Almost any point of sail will do!
This comment intrigued me. Mine doesn't flog because I am normally HIW about 5° on a port tack. I would think, although I never tried it, that wind at your back would cause "flogging".

If you had too much wind in the sails, wouldn't the foil inside the mast bend and prevent free furling?
_____
In a recent post was asked what was my 2nd favorite "extra" on my boat (after autopilot). I said genset, but I am now changing that to ...

In Mast Furling!!

In-mast is just a mechanism. The crew may be finicky.
Jim...
 

capta

.
Jun 4, 2009
4,766
Pearson 530 Admiralty Bay, Bequia SVG
This comment intrigued me. Mine doesn't flog because I am normally HIW about 5° on a port tack. I would think, although I never tried it, that wind at your back would cause "flogging".
If you had too much wind in the sails, wouldn't the foil inside the mast bend and prevent free furling?
Jim...
Obviously, I can't furl too close to DDW unless the wind is extremely light, but easing the sheet and slacking the outhaul on any other point of sail seems to work fine. If only I could roll up the jibs with as little flogging.