In mast 'piece of crap' furling system

[planoron]

Lots of good advice, The only thing I might add concerns the sail. I was having problems and pulled the sail. It was older and had a belly in it that was causing problems along with a boom angle not set right. For $400 I was able to have the sail recut and they were able to tell me the angle on the boom I needed to use. While out I was able to clean and use the selden grease to lube. Ordered a new sail anyway due to wear and uv damage to the leech. Got a great new sail in and now have an emergency main should I ever need it.

Second, the furling jumps or misses the groves on the furling post. Are talking about the luff pulling out of the track? If so get a new sail

Good luck

 

[JamesG161]

I was at my boat and took a picture to show all what I tried to put in words, above.

I hope this helps more.
Jim...

 

[Perfect Excuse]

I had trouble with my system too...did all the stuff folks recommended...luff tension, halyard tension, etc. What seemed to make the most difference was two things. 1: I lubricated the gears on the furling winch on the mast, and cleaned all the blocks the sheet, outhaul, and furling lines went through. 2: bought a new sail. Works fine now. I can furl/unfurl without winches, and the boom angle and topping lift setting don't seem so critical. A couple of weeks ago I had a "new" issue come up...the outhaul came off the sheave in the end of the boom near the mast..that introduced a huge amount of friction and I couldn't get the sail furled until I discovered and resolved it.

Good point. thanks, Bob

 

[Perfect Excuse]

Thanks to everyone for the great input. This is my first opportunity to read and respond as we have spent the last month in the islands and Baja between Bahia Conception and La Paz with little internet connection. We arrived in LaPaz just yesterday, the whole time "mainless" and several cruisers along the the way offering help. My intent is to try all suggestions starting with halyard tension to outhaul car location, plus having a sailmaker assess the sail. Rereading my post, I realized more emotion poured forth than intended, so again thanks for all your well thought out responses. Our in intent is to cross the Sea of Cortez from La Pas to Mazatlan, but only after solving the main issue, so I will post what solution I achieve.

 

[Perfect Excuse]

I was at my boat and took a picture to show all what I tried to put in words, above.
View attachment 117668

I hope this helps more.
Jim...

Thanks Jim. The picture are a great help. I will try to approximate your boom angle. It is much steeper than I have tried, in fact, it had been suggested to pull the boom down as far as possible.

 

[JamesG161]

I will try to approximate your boom angle. It is much steeper than I have tried, in fact, it had been suggested to pull the boom down as far as possible.

The angle is determined by the cut of the sail and NOT by the rigging or other adjustments.
Find the angle for YOUR boat. By doing this, you yield the least force to unfurl and minimum wrapped diameter in the mast.

If your sail is stretched (bellied like mine was), imagine if your boom angle was 90° and you put maximum stretched cloth and diameter at the FOOT of the sail (jamb time).
BTW I miss labeled the Gold typo at 90% not 90&. It was really weird to see the sail track parallel to the boom until about the last few feet. The reason why...
My sail is NOT a 90° right triangle but more of a 80° triangle with the luff.
Good Luck and maybe Santa will bring a nice gift!
Jim...

 

[Gene S]

I have a Charleston spar furling mast on my Delphia 37. I'm having furling issues too. I tried lifting the boom like the picture and it was much easier to deploy the sail and retract it.

 

[Crazy Dave Condon]

As a former Hunter dealer, there are many good suggestions as to why things can go wrong. When Geal(not sure about spelling) at Z Spar first called and asked what I thought about in mast roller furling for Hunter sailboats, there was a lot of discussion but one item we both agreed upon. The mast itself can be raked but what ever you do, it has to be straight. If there is the slightest bend, The middle of the furler with mainsail furled in will jam in the middle of any mast where the bend is(a lot here is tuning). The second item we discussed was the position of the outhaul because if it was too close as Captain Pat observed you are pulling down and needs to be further out to pull the foot out easier(make sure the mainsheet is not so tight pulling boom down). The next items were the tightness of the main halyard inside along with the tightness of the furled sail inside the mast. The rest of course was maintenance and sails. Generally, I followed the above to alleviate the problems but one issue that still is a mystery here not much mention of a straight mast and when retuned with any prebend, that created a lot of issues.

 

[JamesG161]

the mast itself can be raked but what ever you do, it has to be straight. If there is the slightest bend, The middle of the furler with mainsail furled in will jam in the middle of any mast where the bend is(a lot here is tuning).

I urge all to check with the Designer of YOUR boat.

Straight from MY boat's Hunter manual.
"The amount of BEND desired depends on the way the sails are cut. As a general rule, however, a calculations based on .07 of the height of the masts above the boom can be used to determine the normal mast BEND."
This is for Hunter's B&R rig on a boat in 7-8 years in production. Mine was mid range of those years, 1997.
My in-mast furling now WORKS with a bend of about 9" and a 59' mast by Z-Spars.

I am not posting this to argue, but for all to consider the many aspects of in-mast furling.
Think about YOUR boat and research YOUR boat, as I had to do.
With my ≈60 feet and ≈9" bend is nothing in a hollow mast with ≈6 " of frees space inside, where 9" in a say 30 foot mast is a lot. With MY furled sail, there is still about 2" of free space between the wrapped sail and inside of mast.

One reason for pre-bend is to prevent mast moving in high winds and fatiguing the aluminum over time.

When the sail is unfurled and in a beam reach, the inside furling tube (foil) is bent and conforms to the mast BEND. When no/slight wind in the sail, the foil straightens and is free to turn in side MY mast.

Even if there is drag or friction of sail inside the mast, what does that have to do with a Jamb in the Slot?
( ouch my back hurts from more resistance to sail furling/unfurling)

Note Ralph's pictures of mast cross section with furled sail in side HIS mast, in post#8, picture #2.

Jim...

PS: Z-Spars still makes in-mast furling and if YOU have their mast, check their web site for more info on "how to's" for furling.

 

[uncledom]

This is from the Selden B&R section of the mast manual.

The amount of a pre-bend depends on the cut of the mainsail. A general rule is that the pre-bend should be 1% of the distance from the masthead to the gooseneck, measured at the centre of this distance. The mast must have no lateral bend. All pre-bend must be in the fore- and-aft direction.

I changed nothing but my seven year old Doyle sail to a laminate sail with laminated sun cover (thick sun shade is mentioned as a don't in the Selden manual) and 90 lb children furl and unfurl my main. Of course all the dimensions were checked but the baggy dacron sail was the problem.

 

[JamesG161]

The amount of a pre-bend depends on the cut of the mainsail. A general rule is that the pre-bend should be 1% of the distance from the masthead to the gooseneck, measured at the centre of this distance. The mast must have no lateral bend. All pre-bend must be in the fore- and-aft direction.

Well that makes at least 2 boats that use in-mast furling with a pre-bend.

I decided to show the pre-bend on my boat using an updated picture from my post#22. I added two new graphic lines on the fore side of my mast edge (purple sloped and orange vertical). The gap is the pre-bend and note the max bend is where the two lines cross. The purple bend line is "cheated" to aft to compensate for the un-shown mast head (≈20' higher).
Hmmmmm? Right where maximum force is applied by the boom in high winds. Also note there is no furled sail below the boom( furling starts at the bottom of my up pointing red arrow) and very little furled sail where it is "conceptually" dragging inside the maximum mast bend point (if you set your boom angle right).

Make sure YOUR boat's rigging matches your sailing practices and equipment.
Happy furling!
Jim...

 

[Crazy Dave Condon]

I will still stand by a straight mast but even 1% is not that much. Many of the in mast roller furling issues were with the tuning of the mast with too much prebend as the number 1 issue I saw (has nothing to do with rake of masrt) and with other issues mentioned thus far. . Some phot

 

[Dan_Y]

We had a jam unfurling the 3rd time we used our h36. During the 2nd sail, I mistakenly changed the boom angle using the topping lift. The boom went from about 6" above the traveler car to about 12-15" above the traveler car. This gave a better 'back and down' pull angle I thought would help get the barber pole wrap. Before the 'adjustment', the outhaul had a 'down and back' pull. Furling in appeared to go well but when we unfurled next time... it jammed.

The answer for us is to furl with the weight of the boom on the sail... that sets the correct angle and leech tension for my old sail. No critical thought needed...So the boom block and traveler car block almost touch and the rigid vang is fully collapsed in kickstand mode.

The other big help was to reduce the main halyard tension so the foil could turn easily. I use the winch to tension the halyard a tiny bit more than I can by hand - furls in/out much easier and sail looks good at that tension.

As Jim and the Selden manual point out, correct foil tension allows the foil to bend back against the slot over almost the entire length of the mast to take the sail load. My mast has a few inches of prebend. With the foil against the slot the prebend mast shape can flatten the sail some (if the Doyle sails a are cut to take advantage of the prebend. My sail maker loved the prebend on our conventional h30 mast. When furling, the Admiral keeps one wrap of the outhaul around the winch, we get on a 10degree stb tack, ease the main sheet free, then I furl in with the endless line. In fact now when I think the main is binding in the mast, it's actually the Admiral not easing the outhaul enough. The outhaul tension is low enough to allow the foil to be straighter for furling I would guess. Note the vertical battens were discarded by the PO.

Our main is getting baggy, so I'm interested in the sail uncledom had made!

 

[JamesG161]

As Jim and the Selden manual point out, correct foil tension allows the foil to bend back against the slot over almost the entire length of the mast to take the sail load. My mast has a few inches of prebend. With the foil against the slot the prebend mast shape can flatten the sail some (if the Doyle sails a are cut to take advantage of the prebend. My sail maker loved the prebend on our conventional h30 mast. When furling, the Admiral keeps one wrap of the outhaul around the winch, we get on a 10degree stb tack, ease the main sheet free, then I furl in with the endless line. In fact now when I think the main is binding in the mast, it's actually the Admiral not easing the outhaul enough. The outhaul tension is low enough to allow the foil to be straighter for furling I would guess.

Well there are now 3 boats with in-mast furling , with prebend.

Outhaul tension is more as your sail stretches. My new sail required only tension to keep lines clean flowing or Ziltch. The baggy sail needed outhaul tension to make the sail wrap tightly.

The boom angle depends on YOUR sail cut. I am now in the camp of if you check your sail's, foot to luff angle, that would be calculated from 90° (right triangle) - (Your sail cut Angle) = boom angle.

As Jim and the Selden manual point out,

Mine was from MY Hunter's manual for Z-Spars. Note the similarities.
Jim...

 

[Dan_Y]

Crazy Dave has me thinking though that I need to measure the prebend in my rig for when I have new sails made. Maybe too much more prebend will cause problems and it looks like Hunter's prebend for the h36 is slightly under Selden's nominal recommendation. The h36 sail plan shows 12.5 degrees of mast rake (seems like a lot but she balances pretty well) and 10.45 cm (4.1")of prebend. The Selden tuning guide for B&R rigs shows prebend should be 1% of distance from goose neck to masthead (P), with a max of 2%. That's just over 5" of prebend and the hunter drawing shows about 4.1". Maybe Hunter reduced prebend for in-mast systems, but the drawing shows only a difference in foot length and roach between in mast and traditional.

 

[Crazy Dave Condon]

DA,
When Z Spar came out with the in mast furling mast, so much was discussed about prebend of the B & R rig. Everyone keeps talking about prebend and some say 1% or something that is not much to worry about but too much can be an issue.
Think of it this way. There is tube rolling up a sail in a confined space. When that space is bent, then you bend the tube with sail and it will compress above and below that bend. This was the most common problem in the early years for the mainsail not to roll either in or out. Then there are other issues like a loose main halyard, angle of boom, outhaul block and so on as pointed in previous posts. When there was a problem, the first thing to check is the bend of the mast, not the rake. Second was the main halyard, boom, etc... Remember folks, prebend and rake are two separate items

 

[Perfect Excuse]

Well a big thanks to you all. JamesG161's photos really helped. Thanks for the extra effort to which you went. As a result, I added an extra line to the outhaul car. The line extends aft to the end of the boom and I can use it to pull the car aft when unfurling. The boom angle which parallels the sail foot makes it easier to unfurl. My next fix will be to reduce the angle that the furling line goes into the furling spindle. Currently, it is too steep and causes the line to wedge between groves or to skip a grove. Haven't quite figured our how to do that. However, I have reduced unfurling time from hours to about ten minutes and it does still require some going to the mast and physically pushing on the sail to get things working, but with further tweaking I should be able to eliminate that effort. The next addition to my bag of tricks is to try Sail Glide ( I believe that's the name) to help the sail slide out. Haven't been able to locate any as of yet. We are preparing to cross the Sea of Cortez to Mazatlán in a couple of days and I am much more confident about sailing without being accompanied by diesel fumes. Much appreciated!

 

[JamesG161]

I installed my new main and furled and unfurled with easy.
@Perfect Excuse I hope you are becoming as one, with yours!

Jim...

 

[Digger54]

My FIX… and it works great.
Had a 36 in mast main furling- never had trouble with it. Bought a 41 AC with vertical battens and suffered a year with jamming until-
learned to adjust topping lift, vang and outhaul to allow boom angle to be positioned correctly. What the manual does not tell you nor have a read in any forums, is that when unfurling, your pull from the clew should cause equal tension on both the foot and leech. Any variation can cause jamming Because the part not getting the tension will jam. With my original sail, when I unfurl, the boom is conspicuously raised 2 ft above my traveler. But my furling systems works perfectly now.

 

[JamesG161]

This entire Post is the most complete post on

IN-MAST Main Sail furling

Jim...