Steadying sail design/rigging?

[SteveK]

Deploying when the boat is rocking and rolling is not fun. Seldom does a sailboat motor into a wind and then set sails. Sailboats have the gear in place. Anyway, I ruled out a steady sail when had had the GB with mast and boom.

 

[LeoKa]

This is ours in use. If you are anywhere in the Puget Sound area, the Sailboat Wrecking Yard in Lynden, WA is a great source for used sails.

What is the size of your sail? Steadying or propulsion?

I do drive to Seattle every couple months. I will look them up.

 

[Bob Cofer]

What is the size of your sail? Steadying or propulsion?

I do drive to Seattle every couple months. I will look them up.

It is for steadying. 7' on the foot and 8' on the mast.

 

[LeoKa]

I've measured my setup yesterday. Boom 10', mast 9'. Mast end x boom end 13'.
The boat is 32T empty, 36T loaded. Draft 7.4', beam 14.2'.

 

[long-cours.62]

I see. So the purpose of your sail were propulsion, not steadying?

The jib was fitted because ...the mast was already here and we we already had this jib.
The main sail could be used for both.
In our example 15kts of wind could make a "pressure" of 3.8 kg per sqm x 17 sqm x by the high of the center of the main sail it dampen the roll. even "only" the inertia given by this weight dampen also, it change the...don't know the term in English :-(
And if need to use like only a steady sail it is relatively flat sail and full battened, it do the job.

 

[KnotYet]

Deploying when the boat is rocking and rolling is not fun. Seldom does a sailboat motor into a wind and then set sails. Sailboats have the gear in place. Anyway, I ruled out a steady sail when had had the GB with mast and boom.

I can assure you that most sailors prefer to raise sails while luffing (pointing into the wind) to minimize the effort needed to overcome the friction of the hanks or cars and track.
Setting, which to me means trimming, happens as you fall off onto a chosen course.

 

[Marco Flamingo]

Given what you have said about your vessel's stability in other posts, I don't think that a relatively tiny "steadying sail" would be of any benefit. It could even make things worse. It's probably time for a real stability analysis and determine what, if anything, can turn the boat back into a coastal cruiser.

 

[LeoKa]

And if need to use like only a steady sail it is relatively flat sail and full battened, it do the job.

Thank you for sharing. This is very useful information.

 

[LeoKa]

Given what you have said about your vessel's stability in other posts, I don't think that a relatively tiny "steadying sail" would be of any benefit. It could even make things worse. It's probably time for a real stability analysis and determine what, if anything, can turn the boat back into a coastal cruiser.

I hear you. Nothing is final on this, yet. I might just totally abandon the idea, but for now, I wish to hear others' opinions and experiences.
Who knows, the mentioned tarp test might not deliver any significant results, so it will not make sense to spend money on the properly designed steadying sail.
If I wanted to order stability analysis, I would properly do it for a more serious solution. My boat is not a high-end vessel, so serious money spending might not be justified.

 

[SteveK]

I can assure you that most sailors prefer to raise sails while luffing (pointing into the wind) to minimize the effort needed to overcome the friction of the hanks or cars and track.
Setting, which to me means trimming, happens as you fall off onto a chosen course.

you sir have replied to a sailor, the OP however may not seem to be one. And as you will know a sailboat headed into the wind is more stable than a powerboat.

 

[GoneFarrell]

I'll throw this in as food for thought..

Banner Bay Marine Store

Banner Bay Marine offers Anchor Riding Sails. Be safe, sleep better at night.

www.bannerbaymarine.com

It's an anchor riding sail. I have not used one, have seen one in the San Juans. If I get industrious I will prototype one from tarp material this season as my boat can tramp bad on anchor.

 

[psneeld]

Getting sidetracked on riding sails is usually the demise of decent discussions of steadying sails..... which I think was the OP idea.

 

[psneeld]

Steadying sails use air resistance (nothing to do with propulsion and why they don't need sail "shape") when rolling to reduce the motion the same way anti-roll tanks use the liquid weight opposing gravity to do the same.

Thinking steadying sail have anything to do with sailing is already a bad assumption.

 

[RedRascal]

I've measured my setup yesterday. Boom 10', mast 9'. Mast end x boom end 13'.
The boat is 32T empty, 36T loaded. Draft 7.4', beam 14.2'.

Okay it looks like a $13 test instead of $20 That's a 35% cost reduction, when in boating do you every get a chance to spend 35% less to do something. 9 ft. 4 in. x 11 ft. 4 in. Heavy Duty Reflective All-Purpose Weather-Resistant Tarp

Given that you are only working with about 45 square feet of sail area I am thinking it won't do anything other than provide some shade when the sun is lower in the sky. So back to voting with my wallet and I am thinking I'd rather spend my $13 on a nice apple or key lime pie.

 

[Marco Flamingo]

I'll throw this in as food for thought..

Banner Bay Marine Store

Banner Bay Marine offers Anchor Riding Sails. Be safe, sleep better at night.

www.bannerbaymarine.com

It's an anchor riding sail. I have not used one, have seen one in the San Juans. If I get industrious I will prototype one from tarp material this season as my boat can tramp bad on anchor.

I just bought several yards of spinnaker material and made a delta sail after looking at the $550!!! FinDelta #2. I spent less than $30 on materials and maybe an hour and a half at the sewing machine. Yes, it is lightweight, but I'm only looking to point into the wind better when at anchor. If it only lasts ten years, I'm good with that. I'll start another thread with pictures when I get a chance.

As psneeld said, a steadying sail generally uses the air resistance when flopping back and forth. If the vessel's flop is slow (from low stability) and the mast is short (short moment arm), you get nothing. If the wind is really strong on the beam, you will get "pinned" to one side where the vessel's stability "kicks in" based on the moment arm created between the CG and the CB. With a low stability vessel, that might pin you over with a constant 5-7 degree list (a stability test would give some indication). Probably not where you want to be in a trawler even if the overall roll is reduced.

But I'm all for a cheap blue tarp experiment.

 

[LeoKa]

Getting sidetracked on riding sails is usually the demise of decent discussions of steadying sails..... which I think was the OP idea.

True.

 

[LeoKa]

But I'm all for a cheap blue tarp experiment.

Yeaahhh, welcome to the team.....

 

[LeoKa]

Okay it looks like a $13 test instead of $20 That's a 35% cost reduction, when in boating do you every get a chance to spend 35% less to do something. 9 ft. 4 in. x 11 ft. 4 in. Heavy Duty Reflective All-Purpose Weather-Resistant Tarp

I vote for tiramisu. Not really a pie person.

I like cheap, but sometimes boater need to swallow the expensive whatever. Even, if there is valuable result, I think it is still money well spend of $20. I might just learn something about my boat.

 

[SteveK]

Do you have a fin or full keel on that boat? Either should already reduce rolling. Do test the tarp sail idea before getting a sail made.

 

[LeoKa]

Do you have a fin or full keel on that boat? Either should already reduce rolling. Do test the tarp sail idea before getting a sail made.

Full keel. It is a sailboat hull originally. 7.4' draft. Keel tanks both sides.
Tarp sail first, agreed.

 

[long-cours.62]

One précision concerning our Lo g cours 62 with the orange main sail : maximum stability at 48° is 18476 m/kg

 

[cafesport]

Your mast and boom are not going to provide sufficient sail area. Windsurfing sails are bigger. Put 20 lead pigs in the keel area and your boat will immediately be stiffer.

 

[LeoKa]

Your mast and boom are not going to provide sufficient sail area. Windsurfing sails are bigger. Put 20 lead pigs in the keel area and your boat will immediately be stiffer.

Yea, lead or bilge keels, are still in the picture. The steadying sail is just an idea. The suggested tarp test could answer some of the dilemmas.

 

[Pascall]

We can hoist two sails on our boat, mizzen sail and a jib, together 12 square meters.The boat is 11 meters long and weighs 14 tons.It helps reduce rolling but to a limited extent.In a certain sea state it can help quite well, but it only takes a little change (worse) and it is nullified.In other words, the sail area is too small for the weight of the boat.

Greeting;

Pascal.

 

[LeoKa]

Yes, I think the boat is too heavy for a small sail I can create. I still want to test it with the tarp, but I don't have high expectations.

 

[Davb1947]

I have a mast and a boom on top. I use it to haul things up and down, when needed. It looks very strong and long enough to put up a steadying sail somehow.
My boat is very tender and rolls quite a bit. I am thinking to setup a steadying sail to reduce the roll. This is not for anchorage roll, but rather cruising roll while underway.
I know there is no perfect solution, but it does not hurt to try, since it is not very expensive. I do not know anything about sails, or how to setup and handle sails. I am not looking for anything special (riding sail would be nice for emergency get home solution, but I think that should be a separate sail). The boom and mast has already plates welded on, where I could drill some holes for the rigging. It is aluminum and looks strong. I can swing the boom out for about 50-60 degrees in either direction, if that is useful for this purpose. View attachment 154281View attachment 154282View attachment 154283View attachment 154284View attachment 154285View attachment 154286View attachment 154287
Anyone has done it alone, or it has to be ordered and manufactured? I took few photos of the mast/boom, so you can advice me what fits, or not?
Thanks.

I own an Albin 36 dual engine trawler. It came with a gaff-rig and a sail made of brown Dacron by Hood. I have played with it at anchor and underway. My observations based on experience:
1. It makes some small difference in a rolly anchorage. The gaff (the upper spar at the top of the sail) should be fully raised to its highest position and the boom (the lower spar at the foot of the sail) sheeted in tight (ie, the line that controls the swinging of the boom pulled in as tightly as possible). The sail will fill with air on one side when the boat rolls in that direction, then fill with air on the other side (likely with a snap and a whoomp) as the boat rolls the other way. This will serve to dampen the rolling slightly. The tighter the set of the sail - the flatter it is sheeted in - the better as it will act sooner and “whoomp” less. I seldom use it unless things are really uncomfortable as the setup and the “whomping” aren’t worth it.
2. Underway pretty much the same things apply as at anchor - assuming there is not strong wind blowing across your course. The wind generated by the boat’s speed (aka, apparent wind) will be on the bow at whatever your boat speed is. With no wind blowing (aka, true wind), the sail will respond only to the apparent wind and can be treated like you would at anchor. If there is true wind and boat speed wind, then the perceived (apparent) wind will be the resultant of the two wind vectors. If the wind were coming from directly behind you, and matched the speed of your boat, you would feel no wind at all. If it were coming from 90° to your course, it would feel as though it were coming from that side but somewhere between your beam and your bow. The angle of your sail to the apparent wind is a matter of experience. I don’t bother with the steadying sail underway except when there is little to no wind and a very rolly sea. Then I might set it to see if it helps. Often it doesn’t.

Conclusion: it looks great, very traditional and nautical, but of little practical use to recreational sailors. But fun to play with.

 

[LeoKa]

I don't think I could create sail of that size.

Conclusion: it looks great, very traditional and nautical, but of little practical use to recreational sailors. But fun to play with.

 

[kapnd]

Full keel. It is a sailboat hull originally. 7.4' draft. Keel tanks both sides.
Tarp sail first, agreed.

This explains your rolling problem.
The boats design relies on a heavy deep keel with an opposing tall, heavy mast to counterbalance it.
The original mast being removed has created an imbalance, which causes the uncomfortable situation.
So to remedy the problem, you do need a taller mast, and incidentally, your boat may perform beautifully under the correct amount of mast and sail.

 

[LeoKa]

This explains your rolling problem.
The boats design relies on a heavy deep keel with an opposing tall, heavy mast to counterbalance it.
The original mast being removed has created an imbalance, which causes the uncomfortable situation.
So to remedy the problem, you do need a taller mast, and incidentally, your boat may perform beautifully under the correct amount of mast and sail.

I don’t think there was another mast on this boat ever. The original builder created the upper structure himself. Only the hull plan was from a designer and he he bought the kit to build it.
There were rolling chocks welded on the hull at one point, but it was removed. Who put it on, who took it off and why; I have no clue. I am the 4th owner.
Regardless, you are making a very important observation about the mast. This is something I could consider, since it can be fairly easily replaced by a yard. Even if I have to migrate all the existing attachments. The mast is aluminum now and looks sturdy. My question is: do I want a heavier and taller mast, or just taller? The boat is top heavy already, so a heavier mast might not do good.

 

[kapnd]

Thanks for posting the shots of the hull, this is really interesting!
It looks to me like the “fantail”? flat area that the rudder hangs from is added on to the original hull, completely destroying the sleek lines of the original displacement hull shape, and obviously creating a good deal of drag as well as throwing some square chine into the mix to further confuse the hull design.
I’m sure you could open up some interesting discussion about your hull over at boat design.com, if you are interested in understanding what’s happening down there!