Jump to content

Roller furling mainsail?


IsZataRock

Recommended Posts

I learned a lesson today.  Don’t leave a posting long enough to go take pictures.  I had a long one all set to go, shot a couple pics, came back and found it gone.  Arrgh!  It’ll be cut and paste from Word in the future.  Well, ok, let me try again:

 

It’s fall in Colorado and time to start work on Phase 2 of my CS17.3, Just In Time.  I launched her in early September as a motorboat just so I could get on the water this year.  Now it’s time to do the “sailing parts.”

 

I’m wondering if anyone has given thought to arranging the main sail with a roller furling around the mast.  It’s doable, of course.  I did it for a downwind sail using an old windsurfer mast and a Polytarp sail. (see pics).  I slid the hollow windsurfer mast over an aluminum tube I connected to tabernacle.  It could also be done using a larger pivot tube (or better, pivot bearings) into which the 2.5” mast is inserted.  I’ve thought of a few pros and cons:

 

Pros:

  1. No more need to go forward to raise and lower the sail.  Maybe there’s a way to do this from the cockpit that I haven’t figured out.  Or ways to safely go forward while leaving the helm unattended in bad weather.  Any help from the experienced folks in this forum would be great.
  2. Fast, infinitely adjustable reefing.
  3. Simple, clean, sleeve connection between sail and mast.

Cons:

  1. Pretty tricky fitting a pivot tube in the existing tabernacle to enable use of the standard mast.  Hah! Mine is only screwed in at the moment so maybe I make a bigger one?
  2. Furling loads might get pretty high if the pivot tube is too short and/or there is too much friction in the bearings.  HATE not being able to furl when the wind kicks up!
  3. Sail has to be cut differently.  No roach, no horizontal battens.  Maybe just go a little slower or maybe use an angled, Hobie Adventure Island type batten.
  4. Boom configuration needs to be changed.  Maybe a deck-mounted boom pivot or accept the compromise of a boomless rig?
  5. Bad sail shape when reefed.  Not too worried about this.  Slab-reefing sorta messes up sail shape too.  Even a flat triangle that far forward should help balance the mizzen pretty well.

What am I missing? 

 

Hal

post-4028-0-54126500-1444067594_thumb.jpg

post-4028-0-92810200-1444067608_thumb.jpg

Link to comment
Share on other sites


Hi Hal,

Sounds like you having some fun with your CS17.

 

On my CS20 I ran the halyard, 3 down-hauls and the snotter back to the cockpit so I could lower sail, reef etc. from the cockpit. I tend to over-complicate things. Once I got it set up right I could pretty much reef the main from the cockpit. I still had to move the snotter at the clew and  go forward to tie the reef nettles so not a perfect solution. But I could adjust downhaul and snotter tension from the cockpit. 

 

 

I look forward to see what suggestions people on the forum make.

Link to comment
Share on other sites

If the mast fit into the pivot collar, the bearing surface would be larger, plus, maybe you could attach a boom to the pivot tube with jaws? If the tube were large enough, you maybe be able to bush it with something tough and slick inside, too.

Then the outer end of the sprit could have a tackle as an out haul you could slack as you rolled up sail.

I really don't know, as I've only had the 4 sided type of sprit sail, and always loose footed. Well, and some lug sails...

A potential solution intrigues me, though.

Link to comment
Share on other sites

I have a Sea Pearl 21. Roller furling is great. For single handing in rough water, it's tough to beat. I've had my SP in water I shouldn't have and with the sail less than half of it's sail area felt safe. She doesn't go to weather that great when reefed, but in sailing with many other popular traditional small boats seems to outperform them (no CS boats though). The downside is that you need to go to the mast to turn it to reef. Marine Concepts has a pretty good setup that allows a lock with a pin. getting a reefing schedule allows the boat to stay balanced over a wide variety of conditions. There is a pretty good video on you tube called Sea Pearl rigging that shows the setup.

 

The biggest advantage I think is that the sails stay on the spars. I can rig my SP in less than 10 minutes, with the sails ready to set in 20 seconds each. The sails stay nice and unwrinkled, and you have no stowage problems. If that could be incorporated into the tabernacle, it would be even better. I hate folding sails and stowing them.

 

That said, my plan is to build to spec, as I don't see many complaints about the stock rig. If I feel that the SP setup offers advantages I may change down the road.

 

Take Care,

Steve

Link to comment
Share on other sites

Finally got out to try my downwind rig yesterday afternoon.  SO NICE to be able to sail - even if it's a little on the slow side and restricted to broad reach or lower off the wind.  I still haven't built my rudder or figured out how to get both the rudder and the 6 hp on the same transom.  So I used a transom oarlock and 8' oar to steer.  I found it interesting that the boat seemed to have weather helm with my terribly unbalanced (toward lee helm) rig.  But then figured that it's just that it was just the huge leeway (no centerboard yet either!) that pushed the oar blade to weather.  Being creative, or lazy, I stopped steering and found she'd head up a bit, then fall off, until gradually coming to a happy equilibrium in a deep broad reach.  HAH! that's a nice, unexpected point of sail!

 

It was also instructive to practice ducking through my cabin to reach the forward hatch and then ducking again to get out.  I chose to build the two-hatch version of the Mk3 rather than the tunnel hatch to better ensure water tightness.  But it does require a bit of contortion to get forward. On the other hand, the boat was well behaved while I was dinking around forward.  And standing in the cabin with a hatch around my upper body is WAY more secure than crawling up there on deck. Life is full of trade-offs, yes?  

 

Thanks for the feedback, Terry, Robert, and Steve.  Terry, it's that need to secure the loose sail.  I don't see any practical way to achieve that from the cockpit. Steve, thanks for the reminder of the Sea Pearl rig.  That configuration is close.  The bearing loads are (roughly) inversely proportional to the distance between them.  And the SP's bearings look to be very close together in the hull.  No wonder you have to rotate the masts by hand.

 

With the hope of being able to back out of this experiment without having to rebuild my mast, I'm thinking of using a 2.25" od, non-rotating post that will be inside the 2.5" lower section of the standard mast. I can then use the standard mast without any significant alteration (except I won't need to mount the track).  That'll give me a mast that's 18" taller than design and some bigger loads on the tabernacle then Graham calculated if I use the standard-size sail.  So I'll want to be quick to reef.

 

I'm leaning away from a boomless rig.  Seems like there are some decent options for a low goosenecked boom.  Though I'll miss the elegance of the sprit boom's use of the sail's foot, rather than a vang to keep horizontal off the wind. 

 

This all seems reasonable.  But I have this nagging feeling I'm missing something.  Especially since nobody else has done it.

 

Hal

Just In Time, a new Core Sound 17, Mk 3

and a gazillion other small boats in my back yard, shed, basement and garage

Link to comment
Share on other sites

Hal,

I had sleeve luffs on my CS17. I had a 1 inch hole drilled through the mast and a section of heavy-walled tube welded to give me a horizontal hole near the base of the mast. I would insert my 'mast wrench' (Graham called a mast spanner.) and it wound up the sail very neatly. I did have to go forward, but my foredeck was very short and I was still IN the boat. Once forward I could loosen the snotter and unhook it from the D-ring on the mast, wind in a reef and re-attach the snotter. Tricky part was where to attach the snotter. I had a strap with a D-ring sewn on to the sail. It worked, but could have been better. That was in 1997. I have a few other things I'd like to try.

Link to comment
Share on other sites

Yeah, Gordy.   That snotter connection isn't easy.  Seems like a nicely-shaped hook (jaw?) would work for the sprit's axial load.  It probably wouldn't slide down once tensioned up.  But it would slip down any chance it got.  There's always a good reason why experienced sailors rig their boats the way they do.  Still I can live with a compromised downwind sail trim.  So the sprit problem isn't a killer for me.

 

How easy/hard was your "spanner" mast-rotation method?  How far up was the top bearing from the bottom bearing?  I'm hoping to get the bearings far enough apart and configured well enough to allow use of a drum for furling.  My current setup has "bearings" 2.5' apart that are just fiberglass on aluminum with a liberal dose of petroleum jelly for lubricant. I can furl my 60 sq ft sail on it's 15' mast with a very light pull on my 4" dia drum.  I learned this "drum" trick from an Adventure Island I sailed for a month or so.  It is awesome!  

 

Hal

Link to comment
Share on other sites

"Steve, thanks for the reminder of the Sea Pearl rig.  That configuration is close.  The bearing loads are (roughly) inversely proportional to the distance between them.  And the SP's bearings look to be very close together in the hull.  No wonder you have to rotate the masts by hand."

 

FWIW........I don't think the distance of the bearing loads is not much of a factor. You won't be able to furl the sail at all with any kind of driving sail load on it, and un-sheeted most of the load will be pushing down. On the Sea Pearl, the method is to have two plastic bearings that are sized so that when riveted to the mast are the size of a PVC sleeve (it's actually Schedule 40 PVC pipe) which takes the loads in compression at the deck level and mast step. But most of the furling friction comes from downward pressure of the mast and the rotating goose-neck hardware friction, and of course any sail pressure from the flapping sail. The end cap on the mast is some kind of hard plastic, and many people (including me) slip a thin teflon disk into the mast step. Some guys have tried to make the furling a remote operation like a headsail, but requiring the mast to be held from rotating without a positive stop (the pin on a SP mast locks it from any rotation positively) that good out-haul requires would be a challenge, even with a low stretch line. I use the out-haul tension and vang to depower the sail. I don't have much experience with other rigs (loose footed, sprits, etc.) so I can't comment much. My kids when they were no more than 10 could rotate the masts, and pin them. I would handle the out-haul.

 

I hope you figure this out. Having an infinitely adjustable reefing is a sweet thing to have.

 

Take Care,

Steve

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

Supporting Members

Supporting Members can create Clubs, photo Galleries, don't see ads and make messing-about.com possible! Become a Supporting Member - only $12 for the next year. Pay by PayPal or credit card.




×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.