Sailing on the main alone

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BudStreet
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Sailing on the main alone

Our boat won't. That is, it doesn't want to. If you get it sailing downwind with the genny up and then roll up the genny it will continue sailing downwind. But if you do anything to bring the wind forward of the beam it will refuse to sail. Can't do a chicken gibe, it will not make it around even with 5 knots boat speed going into it.

Typically, the thing will just sit there and slide sideways through the water with the nose pointed into the wind at about 50 degrees. It should sail, but it doesn't. The helm does nothing, put it over either way and it just stalls. Even if you get some forward boat motion the helm does nothing. Sometimes it will drift backwards as it slides sideways, but mostly it just slides sideways through the water, nicely hove to.

I know why this, too much force too far aft, but what can be done about it? If you put your main alone up, can you actually sail upwind, or even on a beam reach? Or downwind? Ours will do none of these without assist from the engine to get it going in the right direction, and it will not sail to weather or even on beam reach without the engine, it just rounds up into the wind and stalls.

I see other boats sailing on the main alone all the time, especially the racer crowd between races.

I'm thinking you've lost your engine and your roller genny is jammed. Now you're hosed. What do I need to do to make this work?

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Steve Frost
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Posts: 788

Bud, the Kiwi's pulled this off pretty well last Saturday in the Louis Vutton series. They used foils, you may want to try that.

I forgot, do you have a wing keel? I have sailed my boat with main only a few times on the bay, it does not point well but will go up wind barely in a decent breaze. Like a catamaran it requires a breeze, seldom a problem on San Francisco bay, as boat speed increases I can ease further into the wind as the appearant wind moves forward with boat speed. I do not have a wing keel and this may be a factor.

I do fairly often sail with head sail only and find I can point higher with the head sail than the main only. With main or head sail only I find the boat points far better with the scent of diesel in the air. I think it increases the molecular weight of the air giving it more energy.

Cepheus dream
C36 MK I # 825
MK I Tech Editor No Mas

greigwill
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Posts: 174

Bud do you have a furling main?? I sail my wing keel on main alone often,very often in fact,when teaching points of sail...it sails on all points,poorly close hauled but it does it...whats up? BTW,i have a full batten main.

"Sailing Still" 1990 C36 M25 wing
 Sail Canada/Transport Canada training
Gibsons Harbour BC
www.landsendbc.ca

BudStreet
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Posts: 1127

Greig, it's a regular full batten main from Catalina Sails. I've tried several times now and I cannot make this boat sail on the main alone, except with the wind well aft of the beam, off the quarter really, and you need the headsail or diesel to get its ass around into the wind to even do that. I've tried sheeting in tight, out loose, traveler up, traveler down, let it go completely and try to throw the boom around by hand to keep the load off the boat as long as possible, nothing has worked so far.

It sails great on the genny alone in any wind and balances so nicely with both sails. It just seems to me a boat should sail on the main alone.

At least I know if I ever get caught in a real nasty storm I can heave to pretty smartly. Furl the genny, bring her into the wind and sit tight, you'll be going nowhere but slideways. It does that very well, you can see the nice slick form to windward taking the tops off the waves. So perhaps it's actually a plus? A feature, not a bug, as we used to tell clients in the software development world.

greigwill
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That is so different from the way my boat behaves...i have not been able to heave to on main alone but only with a backed jib and main..i have tried it with main alone and cant stop forward movement...no windward slick.Stranger still,we both have wing keels and battened mains...i'm stumped.

"Sailing Still" 1990 C36 M25 wing
 Sail Canada/Transport Canada training
Gibsons Harbour BC
www.landsendbc.ca

BudStreet
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The only difference I see is you're Mk I and we're Mk II, but they're supposed to be the same below the waterline so I can't see why that would make a difference. We have a full bimini and a low dodger which no doubt will increase windage aft of the mast and that won't be helping either, could be enough to cause it though.

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dejavu
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I have to say that I'm a bit puzzled by this. My routine on a daysail is to raise the main as we head down the main channel and then after we clear the breakwater, unfurl the jib and shut off the engine. A few times, we've gotten past the breakwater and the wind was really blowing hard, so we decided to "take it easy" and leave the jib furled. The boat zipped along at 5-6 on a close reach with little heel (the way my friends like it) and we had a great time. :confused:

Mike

Deja Vu
1991 MK I # 1106
Marina del Rey, CA

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Steve Frost
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Mike,

Bud never indicated wind speed, I believe this an important factor. My and your experience coincide in heavier air. My boat does not do well on main alone in light conditions.

Cepheus dream
C36 MK I # 825
MK I Tech Editor No Mas

greigwill
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Could mast rake be a factor?I have a fair amount,5 or 6 inches raked aft..I also have a low dodger and permanent bimini...

"Sailing Still" 1990 C36 M25 wing
 Sail Canada/Transport Canada training
Gibsons Harbour BC
www.landsendbc.ca

BudStreet
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The wind speed when I tried it the other day was 8-10 knots so not much. And other times it's been low as well. I will have to try it when there's more wind and see what happens then.

Our mast is almost straight I have a tiny bit of aft rake in it but it would only be an inch or two at most.

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Nimue
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When sailing with just the main your maneuvers need to be decisive so that you don't burn off all your speed before the sail fills again. We have no trouble sailing just main, but the boat is much quicker sailing with just the jib. This is partly an area thing and partly a balance thing.

Jason V
Vancouver, BC, Canada

windward1
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Posts: 146

Last week while cruising south down the west coast of Lake Michigan with a 10-14 NE wind and lumpy one to three foot waves, we had the main up and were motor sailing. We also were hand steering as the waves were moving the boat around and auto was having a tough time. As the wind moved a little more north behind us we decided to drop the main think this might help as the boom was swinging more. Actually the boat rolled more. I then tried unfurling about one third of the jib and sheeting it tight. This really steadied the boat. I was wondering if anyone else ever tried this when motoring on a broad reach? This was an experiment on my part but was a big improvement.

Richard
1994 C36 Tall Rig M1.5
Waukegan Harbor
Lake Michigan

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stu jackson c34
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Richard, a broad reach inherently means that the waves will be coming in on your aft quarter, which means the boat will corkscrew a lot, compared to simple rolling which beam on seas would make happen. Recreational autopilots do not like quartering seas. Anytime we go downwind, if we choose to relax and not sail hard, the first sail to come down is the main, we let the jib pull the boat.

Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)

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mike37909
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Sailed yesterday with main only in 5 to 10. Sailed fine but only 3 knots max upwind. Mostly 2 knots. Downwind was better around 3 to 4 knots.
Tall rig fin keel. Flat water.

Catalina 36 MK1
1984 Hull #306

 

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heynewt
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Interesting. I sail on Main with the wind ahead of the beam occasionally on my Mk 1 C36. I have a full batten main as well. But it's very sluggish with wind under 8kt. It really doesn't work with any efficiency under about 13kt.

Also, it helps if you settle into your point of sail with the motor and gradually bring down the throttle. I've been in irons in light breezes under main alone, and it was very hard to get going when the wind picked up and I wasn't pointed well for it (but then, getting going from a dead stop under sail while pointing in the wrong direction is an art I've struggled to master).

Robert Newton
At Last
1985 C36

jmflan
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Posts: 6

I hopped online tonight trying to find an answer to the exact problem BudStreet has.  I bought a 1990 36 about 4 months ago; coming off a 1978 27.  Twice now, while sailing under main alone, once in lighter wind and once in heavier breeze, I basically got stuck.  In the lighter breeze I was near home and so tried to play around - sheet, traveller, ease, trim, anything - but no luck.  She would get to about 30 degrees off the wind and nothing more.  There was nothing I could do.  Granted, if I wanted, and could, sail that direction life would have been fine.  But that wasn't the case.  If I did sail that angle, I could get enough just speed to tack and I would end up in the same position on the other tack with no ability to get the wind to the beam or aft.  It became a game of back and forth back and forth and I finally gave up and turned the key.  With the heavier breeze I was a ways from home with approx 15 off the beam.  Got a nice header and I didn't react fast enough and she rounded up quick and I was again stuck.  We unfurled the headsail and after gaining some speed I was able to fall off and everything was fine.  It's just so odd that I also can't sail under main alone.  I have the wing keel and full batten main.

Jeff F,
shenanigans
1990 C-36 (Hull 1069)
Coconut Grove Sailing Club
Miami, FL

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pkeyser
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Jeff-
Lots of good comments in the thread. I'll add one more. In 15+ knots, our C36 MKII does ok under main alone. Much better with heavy air than light and of course, it doesn't point as well as jib alone, but I was pleasantly surprised last year. We have in-mast furling. If memory serves me, the main has maybe 1/3 the total sail area and genoa 2/3rds, so there will be a big difference based on that alone-all other things equal. 

Paul & Wendy Keyser
"First Light"
Newburyport MA/Rye NH
2005 C36 MKII #2257
Wing, M35B

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Anchorsaweigh
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Posts: 30

Lazybones sails just fine on main alone and points pretty darn well. Wing keel, in-mast furling.

I can't figure out what could be causing your problem. Sounds like you're doing everything right. But I'm just returning to 2-sail sailing after 12-years on a Nonsuch.

Just my 2¢

Cheers

Bob

Lazybones - 1999 Catalina 36 MkII, M35B, #1731
E. Greenwich, RI
 

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rkibler
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Posts: 32

Where is the draft of your main sail?  The main sail needs to be similarly shaped as a wing.  If the draft is aft of 50% then the sail will not generate enough lift to pull you any points upwind.  How much twist do you have?  In lighter winds you want the top batten of the main close to parallel of the boom.  I agree 8-10 mph winds the main alone will not get you upwind fast.  But they do sail at 50 deg. apparent.  
Try adjusting the main halyard tension, outhaul tension, and boomvang to get a nice wing like shape.

I know that dragging two crab pots will definitely hinder sailing performance.  haha, could that be the problem? 

Rob Kibler
s/v "Meander"
2003 C36 MKII #2124

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LeslieTroyer
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Posts: 524

Could you be over sheeting before the boat build speed and steerage??

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor. 

Commodore

 

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