Problems unfurling the Main

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MarkElliott
Posts: 29
Joined: Sun Sep 01, 2013 1:41 pm
Location: Eastern Long Island Sound

Re: Problems unfurling the Main

Post by MarkElliott »

Thinking this over, as I have had this problem and replaced the sail with some improvement, but not completely solved, would it pull out easier if boom is Port of center? This way sail cloth is not turning a corner against the edge of the mast opening as it unrolls? I'll try that next time to see if it helps. With more sailcoat also.
Mark Elliott
Mintaka #71
Noank Ct.
JerryRoss
Posts: 29
Joined: Mon Jun 27, 2011 2:02 pm
Location: Pensacola, FL

Re: Problems unfurling the Main

Post by JerryRoss »

I developed a similar problem on my 2005 C350 a couple of years ago. My solution was to tie a line to main’s outhaul block, run the line along the boom, over a spare sheave at the boom end, back through the boom inside, down to a small block installed at the mast bottom, through a spare port side sheave on the traveler frame, then through a spare port side rope clutch. This follows the path of the main’s outhaul sheet except my outhaul sheet goes to starboard while my new line goes to port. I used a 3/8” line for a convenient hand size. To unfurl the main, I first pull the main out as much as possible which is usually only two or three feet. Then I use the new line to pull the outhaul block back about half way to the boom end and close the rope clutch. Then I pull out the main more and it will usually completely unfurl. Sometimes I have to use the new line to pull the outhaul block farther back to completely unfurl the main. I set up this arrangement because it appeared my main’s leech was causing the outhaul to jam on the track until the main was about half unfurled. With the outhaul block pulled farther back, the outhaul sheet gives more horizontal force on the main. I guess this is just an alternative to pulling the main out by hand but I can do it from the cockpit. Good luck.
Jerry Ross
s/v Coquillage
Catalina 350, Hull #350
Mark Sutherland
Posts: 58
Joined: Thu May 25, 2017 1:32 am

Re: Problems unfurling the Main

Post by Mark Sutherland »

MarkElliott, Being on a starboard tack will help the most (if there is some wind) because the wind will a)push the sail away from the starboard edge of the sail groove, reducing friction, and b) the wind helps unfurl the sail, reducing the need to crank on the outhaul and reducing the risk of jamming the foil and sail into the groove. If there is NO wind, then yes, traveling the boom to port will help relieve the friction on the starboard side of the sail groove. You'll also want to set the boom angle correctly as many of us have suggested, and I would encourage you to try presetting the outhaul car aft on the boom as Jerry and I have described.
Last edited by Mark Sutherland on Wed Sep 13, 2017 3:49 pm, edited 1 time in total.
Mark Sutherland,
Dunrobin III
Hull #388 (2006)
Mark Sutherland
Posts: 58
Joined: Thu May 25, 2017 1:32 am

Re: Problems unfurling the Main

Post by Mark Sutherland »

Jerry, on my boat, the Main's (taught) leach is not causing the outhaul car to jam on the track, the taught leach is pulling the flexible middle section of the foil into the interior wall of the mast's sail groove, thus jamming the foil and sail into the groove, like a brake shoe against a brake drum. I can see it when I look up at the jammed top of the leach at the midsection of the mast. As you say, moving the car back transfers the pulling tension away from the leach (and the mid-foil) to the foot and the bottom of the foil, which doesn't flex since it is near a solid bearing carrier. I just moved my car about 80% of the way towards the back of the boom and tied it off there. It slides back the remaining 20% when the clew hits it during unfurling.
Mark Sutherland,
Dunrobin III
Hull #388 (2006)
dedgell
Posts: 39
Joined: Sun Jan 10, 2016 4:01 pm

Re: Problems unfurling the Main

Post by dedgell »

For those who have experienced difficulty unfurling the main, please confirm which mast/furling system you have.

I have the Selden mast/furler on my 2007 boat and have not had a problem. But I had a Charlston Spar mast/furler on our 2004 Catalina 310, and it was problematic. My solution on the C310 was to release vang pressure and only furl or unfurl at head to wind or close to it. I've also found it critical on both boats to keep some tension on the outhaul when furling, or the sail can get overwrapped and jam on the way in.

David Edgell
Blue Wing
C350 #442
Mark Sutherland
Posts: 58
Joined: Thu May 25, 2017 1:32 am

Re: Problems unfurling the Main

Post by Mark Sutherland »

All of my comments on main furling are relative to the Charleston mast that is on my 2006 boat. Yes, the outhaul tension is one key element to a good furl as it helps keep tension on the foot. But proper boom elevation (and it's affect on leach vs foot tension) is also critical to relieving the tension in the leach, which is the main cause of unfurling/foil jamming problems. I differ with Blue Wing however on the relative wind heading during furling. In my experience, a starboard tack orientation during furling places a nice even pressure along the full length of the luff of the sail as it enters the groove and wraps onto the foil, helping achieve the goal of a wrinkle free furl. I did this last weekend in 20+ knots on a low angle starboard tack(35 degrees?); the sail furled nice and clean, and unfurled the next day like butter. During UNfurling, the wind in the sail helps unfurl the sail with less pulling tension on the foil, which helps mitigate some of the tendency for the foil to get pulled and jammed into the sail groove (this is especially true if there was too much leach tension vs foot tension bias during the last furling of the sail). I also believe that setting the outhaul car towards the back of the boom is the biggest game changer. :D
Mark Sutherland,
Dunrobin III
Hull #388 (2006)
PMueller
Posts: 9
Joined: Wed Oct 04, 2017 11:42 am

Re: Problems unfurling the Main

Post by PMueller »

Mark Sutherland wrote: Tue Sep 12, 2017 12:29 am Hi Bob. My 2006 has the Charleston Mast. I stared at my main sail, boom and car geometry an entire afternoon trying to figure out why the main would not deploy smoothly. Here's what I learned, and I haven't had a problem since. The foil(spool) inside the mast is very flexible. If you pull on the center section of the foil, it is easily pulled/jammed into the inner wall of the sail groove, impeding the foil's freedom to turn especially with the main sail material pinched between the foil and the groove. It's just like applying a brake shoe against a brake drum. The question is, what's pulling/jamming the foil into the groove? It's the tension of the main's leach. Notice that when the car is towards the front of the boom and against the clue, the outhaul line points straight up the leach as it exits the car, causing tension straight up the leach and pulling against the center section of the foil, and pulling the foil into the groove, creating a jamming effect. You'll also likely notice that the foot of the main is not as tight as the leach. The key is to change the geometry of the outhaul car and line relative to the leach and the foot. You want the outhaul line pointing more horizontally at the foot of the sail and less vertically at the leach. Pulling against the foot places the pulling pressure against the BOTTOM of the foil. The bottom of the foil doesn't flex since it's very close to a rigid bearing holder, so the foil doesn't get pulled and jammed into the groove. So here's how to make this happen. First, at the dock, manually move the outhaul car at least 2/3 of the way back towards the aft end of the boom. You need to teather it there to keep it from moving forward when you pull on the outhaul line. I tied a rope from the car to the end of the boom. Notice how the outhaul line is now almost horizontal and pointing at the foot and the bottom end of the foil. Feed a little slack into your main sheet (and boom vang down haul if you have one). Raise the aft end of the boom with your topping lift so it's about 5-10 degrees above horizontal. This should provide for a little less tension on the leach. If your sail feeds out of the starboard side of the groove(clockwise), position the boat on a starboard tack, about 40 to 60 degrees off the wind. This allows the wind to help unfurl the sail without having to pull so hard against the foil. Release the tension on the furling line and begin cranking on the outhaul line. Watch the foot and leach as you pull on the outhaul. The tension should be on the foot, not the leach. If the leach is taught, try raising the boom some more. The leach may be taught the first time if it was taught the last time you furled it IN. When you furl the main IN, you again want the tension to be on the foot, not the leach. The leach should be slightly slack(not taught) but not excessively so. You'll need to have the boom slightly above horizontal to achieve needed slack, or sag in the leach. You can maintain the necessary tension on the foot by keeping a little tension on the outhaul as the furling line is being hauled in. This makes the job a little harder for the person hauling in the furling line, but it's worth the efforts as the foot will be nice and tightly wound around the foil when you're done. Note that all of these instructions assume that your leach is a similar relative length as mine. If it is shorter/longer, you'll need to raise the end of the boom higher/lower to ease the tension out of the leach. To sum it all up, you need the foot of the main to be taught, and the leach of the sail to be LESS than taught when furling in OR out, and it helps (a LOT) if you situate the outhaul car aftward on the boom so that it is pulling against the foot, NOT the leach. I hope this helps.
I read this over the winter when I was browsing this forum and it seemed to be exactly the issue we were having with our boat #412 Brilliant. We have followed this advice and had no problem with the main sail this summer. We cruised > 650 miles and pulled that sail in and out many times. We even had a sailmaker look at the sail in the spring to see if there was a problem with it. But following this advice..no problems this year!!! Thank you!
Guinevere
Posts: 43
Joined: Sun Oct 28, 2012 5:31 pm

Re: Problems unfurling the Main

Post by Guinevere »

Started having problems unfurling the main last season. Tried all of the suggestions here but still difficult to unfurl.

We currently have the mainsail at North Sails in Portsmouth, RI for an evaluation. I was anticipating that we needed to have the sail flattened after 14 years of sailing.

They feel that the furling issue is due to shrunken luff tape which they are proposing to repair and to release the tightness in the luff.

Anybody have any experience with this solution to difficult unfurling of the main? Does this sound plausible?

Thanks for any thoughts-
Bob
Guinevere
#243
Triumph
Posts: 256
Joined: Thu Nov 03, 2005 7:34 am
Location: Tampa, Fl

Re: Problems unfurling the Main

Post by Triumph »

Don't waste your time or money. You need a new main. The reason it will not unfurl is that it is no longer a flat sail, it has a big old belly. Recutting doesn't work either. Get a new flat main, period. Several have already been through this.

Otherwise, try this method. When you furl the main in, put tension on the leach. That is, put a lot of vang on. Pull down on the leach. When you unfurl the main, put no leach tension on, release the vang and mainsheet and let the boom ride up high. The main should come out without jamming up top.

Triumph
Last edited by Triumph on Thu Jul 02, 2020 10:04 am, edited 1 time in total.
johnthejetpilot
Posts: 42
Joined: Fri Mar 24, 2017 12:29 pm

Re: Problems unfurling the Main

Post by johnthejetpilot »

I am a somewhat new Catalina 350 owner (bought Ave Maria 2 years ago) and I had the same problems that it seems everyone else has described. The solution that worked perfectly for me was the one proposed by JerryRoss. I did exactly as he suggested in a previous post and it has eliminated any issues I had with unfurling the main in all winds/wave conditions. I am stil using original 14 year old main. It likely will be replaced in the next year or two, but wanted to let others know this solution worked perfectly for me. It really just comes down to changing the angle for pulling the main out. I simply loosen the line when furling back into the mast. I'll try to post pix after she goes back in the water in Lake Michigan in May.
Ave Maria
Hull 212
Kenosha, WI
JohnNorton
Posts: 59
Joined: Thu Oct 13, 2011 12:27 pm

Re: Problems unfurling the Main

Post by JohnNorton »

The lengthy discussion is full of great advice... but I did not see what can be another simpler problem, simple to solve if.... the foot attachment inside the mast (an "s" hook) is not pulled up tight. This allows the "s" hook to lie a bit flat and occasionally catch in the mast as it turns. Solution (hopefully): tighten the main halyard when the main is unfurled.
Triumph
Posts: 256
Joined: Thu Nov 03, 2005 7:34 am
Location: Tampa, Fl

Re: Problems unfurling the Main

Post by Triumph »

There is a lock nut on this "S" hook that if it gets loose, will let the hook lay flat and jam inside the mast. Just make sure this nut is tight and it will hold the "S" hook upright.

Bill
TRIUMPH
Richard Ad
Posts: 58
Joined: Wed Apr 14, 2010 1:08 pm

Re: Problems unfurling the Main

Post by Richard Ad »

I read Mark Sutherland's Sept 12, 2017 post regarding problem unfurling the main sail. I put a custom cover on my boat in the winter and I lower the boom by twisting my boom strut. The lower boom allows the winter cover to drape nicely over the sides of hull. Every year I think I raise the boom back to the original position; apparently not last year. After reading Mark's post I noticed I was pulling down on the leach and the foot was slack. I raised the boom so it is less than perpendicular to the mast and it unfurled pretty well and furled in pretty well. With some tweaking of the boom height my sail now unfurls and furls very nicely. My out haul is now pulling on the foot of the sail and little to no force on the leach.
Thanks Mark for your post.
Mark Sutherland
Posts: 58
Joined: Thu May 25, 2017 1:32 am

Re: Problems unfurling the Main

Post by Mark Sutherland »

Awesome!!! I'm glad it's working well for you! Have a great sailing Season! :D
Mark Sutherland,
Dunrobin III
Hull #388 (2006)
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