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Arlyn Stewart
Master Marine Consultant

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USA
2984 Posts

Initially Posted - 02/06/2003 : 21:55:31

What size are y'alls riding sails?

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

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Dave Bristle
Master Marine Consultant

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Djibouti
10005 Posts

Response Posted - 02/06/2003 : 22:07:17

How about tying a beach towel or tarp to the stern rail, sorta like a little reverse spinnaker?

Dave Bristle - 1985 C-25 #5032 SR-FK-Dinette-Honda "Passage" in SW CT

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Carl B.
1st Mate

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USA
83 Posts

Response Posted - 02/06/2003 : 22:25:20

What is a riding sail? <img src=icon_smile_blush.gif border=0 align=middle>

"OBLIVIOUS" C25 '82 #3098 SR/FK/Trad

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Arlyn Stewart
Master Marine Consultant

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USA
2984 Posts

Response Posted - 02/07/2003 : 08:26:12

Its a small sail hanked onto the backstay and forward hauled towards the mast. It's used to keep a boat from sailing on the anchor rode.

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

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Doug C.
Navigator

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146 Posts

Response Posted - 02/07/2003 : 12:23:42

Arlyn, Sailrite has kits available.

http://secure.sailrite.com/products.asp?dept=157

What do you think?

Doug Cavin
1990 C25 TR/WK #6010
"Valkyrie"

Edited by - on

Arlyn Stewart
Master Marine Consultant

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USA
2984 Posts

Response Posted - 02/07/2003 : 14:17:56

Thanks Doug for the link.... they look like a possilbe way to go.

I posed the same question over on the Trailer Sailor and an interesting point was raised.... that a riding sail was much more effective if it formed a wedge, spreading aft.

Actually this wouldn't be too hard to do and in the process would provide some cockpit awning protection.

Some sketching indicates that 10' x 16' canvas tarp if available at Harbor Freight would do the job nicely with some recutting and bolt ropes sewed in.

Heading to town in a few minutes and see if they have one.

Here is the sketch

http://www.stewartfam.net/arlyn/ridingsail.jpg

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

Edited by - on

Ray Seitz
Captain

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USA
416 Posts

Response Posted - 02/07/2003 : 15:29:18

Arlyn the sketch looks great and I like the Idea of 2 birds with one tarp. Why not use the boom as the main spine of the wedge and topping lift to raise and lower it? The only problem I see would be pressure on the sail/mast connections (those plastic slides-are they called slugs?).

Ray Seitz C 250WB #628 Sea Major

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Arlyn Stewart
Master Marine Consultant

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USA
2984 Posts

Response Posted - 02/07/2003 : 15:45:54

Ray, I think the sail would have to be considerably higher on the backstay to offer a wedge shape to wind ahead than lying it across the boom would provide.

Across the boom starts it at near a horizontal position and wouldn't induce any wedge shape. I'm thinking it has to go 4-5 ft above the end of the boom.

No sail slugs would be used. Probably a beaner at the backstay with the main halyard connecting to it also. Some lines around the mast on its forward end (remembering that the sail cover will be on) and some lines on the aft two corners going to the stern cleats.

My rough dimensions are 10 foot across the back bone, 12 foot on the sides and 8 ft down the aft sections.

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

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John Mason
Admiral

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687 Posts

Response Posted - 02/07/2003 : 16:09:38

I think I'd make the luff a bit more vertical than you have it in your drawing. Less chance of the wind getting underneath and ballooning it.

John Mason - Ali Paroosa
1982 - FK/SR #3290

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Carl B.
1st Mate

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USA
83 Posts

Response Posted - 02/07/2003 : 16:21:19

Now I know what I'm going to use my old mainsail for. What do you'll think?

"OBLIVIOUS" C25 '82 #3098 SR/FK/Trad

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Doug C.
Navigator

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USA
146 Posts

Response Posted - 02/07/2003 : 17:21:45

I like the idea of a riding sail / tarp combo. Could stop the swinging and provide nice shelter from that Bahamian sun!

I'm curious about the size though looks like it is pretty big. Maybe too flappy?

Doug Cavin
1990 C25 TR/WK #6010
"Valkyrie"

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John Mason
Admiral

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USA
687 Posts

Response Posted - 02/07/2003 : 17:31:32

I think it's a good use for old sails. From my understanding a "traditional" riding sail should be flat, but Arlyn's rewriting the book on that with the new, improved V design.

I know in windy conditions my Cat swings back and forth quite a bit. It's more noticable on a mooring buoy than at anchor (shorter pendulum or moment arm?, I'd guess). Tends to drag my crab pots back and forth. Poor crabs havin' to chase their food across the bottom of the bay. But if I pay out enough line to keep the crab pots stationary, the line gets tangled around the rudder and motor.

It's on my project list.

John Mason - Ali Paroosa
1982 - FK/SR #3290

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Ray Seitz
Captain

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USA
416 Posts

Response Posted - 02/07/2003 : 17:39:51

Better start working on the patent Arlyn seems like a real winner.<img src=icon_smile_big.gif border=0 align=middle><img src=icon_smile_cool.gif border=0 align=middle><img src=icon_smile_wink.gif border=0 align=middle>

Ray Seitz C 250WB #628 Sea Major

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Arlyn Stewart
Master Marine Consultant

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USA
2984 Posts

Response Posted - 02/07/2003 : 19:24:27

John, a bit more verticle might be in order... I got the wedge idea from someone on the Trailer Sailor.

Also, this link was offered with some good stuff.

http://www.sailrite.com/techtalk/riggingthesail.htm

Doug, it looks big to me too, the bolt ropes would definately have to have some curve to keep them from flapping. I will amend the drawing.

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

Edited by - on

Arlyn Stewart
Master Marine Consultant

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USA
2984 Posts

Response Posted - 02/12/2003 : 20:32:47

Making a little progress on the riding sail. The first is to be a prototype. It is a combo riding sail and some amount of awning. That is made possible by using the suggested wedge or V design.

I need to know how to deal with making seams on the poly tarp. Is there some double sided tape that can be used?

The design will use curve lines to help keep the edges from fluttering. It will also be secured at the corners by lines so will be easily cut loose if it presents an unwanted hazard.

One of the bunch over on the Trailer Sailor group also suggested the possibility of a aft zippered flap to close the back and further shelter the cockpit. If the rest of it works and it gets built out of canvas, thats a great idea.

<img src="http://www.stewartfam.net/arlyn/ridingsail.jpg" border=0>

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

Edited by - on

dlucier
Master Marine Consultant

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Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 02/12/2003 : 23:37:35

Here's an article I found from
<img src="http://www.boatus.com/goodoldboat/image/head.gif" border=0>

Quit Horsing Around

Use a riding sail to steady your boat at anchor
by Steve Christensen

<img src="http://www.boatus.com/goodoldboat/images/rdsail1a.jpg" border=0>

You're all settled in for the night in that well-protected cove, when the wind picks up. What had been a nice quiet anchorage is now alive with motion as the wind causes the boats to weave back and forth on their anchor rodes. Your boat rolls and jerks from one "tack" to another, and you begin to worry about what all this motion is doing to the set of your anchor. Your nice quiet evening is now anything but restful.

Most people call this weaving back and forth "sailing at anchor." But my favorite nickname for the activity is "horsing around" because the image it creates is so descriptive of the motion. And while the name may sound like fun, the motion it describes can lead to real problems.

What causes this phenomenon? For most boats, the center of effort (or windage) of the topsides and rigging is well forward of the underwater center of lateral resistance. This means the boat is out of balance while on the hook, and doesn't really want to weathercock. Whenever the boat drifts backward during a gust (or there is a slight change in the

<img src="http://www.boatus.com/goodoldboat/images/rdsail4.jpg" border=0>

wind direction) the bow will fall off faster than the stern, putting the boat broadside to the wind. Once that happens, the bow continues to fall off, and the boat will "sail" away in the new direction, up to as much as 30 to 40 degrees off the wind, until brought up short by the rode.

It seems as if the boat should eventually settle down, given a steady wind. But in reality, the wind is never steady in either direction or strength for very long. During the lulls, the boat is drawn forward by the weight of the rode (creating slack), only to fall back and turn broadside during the gusts.

Why all the concern? Well, at the very least, all this weaving back and forth can make things uncomfortable down below. More importantly, it is quite possible for two boats anchored side by side to get "out of phase" while sailing at anchor and actually collide. We witnessed this a few seasons ago while anchored in Bear Drop Harbor in the North Channel on a day with gusty 25-to-30-knot winds. Two nearby anchored boats began to sheer, on opposite tacks, and exactly out of phase. The boats kept getting closer and closer with each tack as the skippers looked on helplessly. A collision was avoided only when one skipper broke the cycle by letting out more rode.

By far the biggest concern of "horsing around" is the effect it has on the set of your anchor. The shock loads on the rode from coming up short on opposite tacks are practically at right angles to each other, and all this stress can eventually break the anchor free. Even if the anchor holds, the sideways motion at the bow can chafe right through a nylon rode in a few hours.

So, if you want to sleep better at anchor, you need to do all you can to reduce this sailing at anchor.

But what can you do? While we've never tried it, a couple of skippers we have met swear by anchoring stern-to. This places the center of effort behind the center of resistance, and keeps the boat steady. (It also looks really weird.) The downside is that some boats are not very seaworthy stern-to, and most companionways are not designed to be very weatherproof from the stern. So I would worry about being caught in a storm anchored backward, but in fair weather it seems to work quite well.

<img src="http://www.boatus.com/goodoldboat/images/rdsail6.jpg" border=0>

The best thing you can do to reduce "horsing around" while at anchor is to use a riding (or anchor) sail. We first learned about riding sails by reading Steve and Linda Dashew's The Bluewater Handbook. It seemed like a good idea, so we had a local sail loft make one for us, and have used it every night at anchor since. The ability of a riding sail to reduce horsing around is just amazing and has to be seen to be appreciated. On that day in Bear Drop Harbor when many of the other boats were sailing up to 40 degrees off the wind, our riding sail kept the bow of our Ericson 38 to within five degrees of the wind direction. Considering how well they work, it is surprising that you don't see more of them being used. (We've only seen one other riding sail in 10 seasons of cruising the Great Lakes.)

Just what is a riding sail? It's essentially a small and heavily built mizzen, rigged on the backstay, and sheeted forward. The added windage of the sail brings the overall center of effort well aft of the center of lateral resistance. Now when the boat drifts backward during a gust and the bow begins to fall off to one side, the effort of the wind on the riding sail quickly pushes the stern in and brings the boat back head to wind.

A riding sail should be constructed board-flat, of heavy (4- to 8-ounce) cloth, with a hollow foot and leech to reduce flutter, and a straight luff with hanks for attaching to the backstay. Adding full-length battens to the sail is also a good idea to reduce slatting in high winds. As for size, a good rule of thumb is to have the sail made about the same size as a storm jib, or from 5 percent to 10 percent of the total sail area. In fact, you can use a storm jib on the backstay as your riding sail. And for that matter, ketches and yawls can achieve the same effect by just leaving their mizzen up (perhaps with a reef or two). But since whatever you use will be left up constantly while at anchor and exposed to a lot of ultraviolet radiation, it's a good idea to have a dedicated riding sail, and not subject your storm jib or mizzen sail to all that abuse.

How do you rig a riding sail? First, attach a pendant between the stern of the boat (the top stern rail works well) and the tack of the sail, long enough to keep the sail well clear over the cockpit. Then attach a halyard to the head and hoist the sail aloft. Finally, rig a sheet from the clew to a place on deck amidships, or - better, but more work - run a sheet to each side of the deck or cabin house. You can leave the sail flying free like this, but it will tend to slat a bit in high winds. So it's best to attach the luff of the sail to the backstay with a number of hanks.

Riding sails may not be common, but any sail loft can make one up for you. Or you can contact Sailrite, which markets a basic anchor riding sail kit with a 75-inch leech, a 58-inch luff, and a 72-inch foot (15 square feet) designed for boats over 20 feet. It costs between $68 and $73, depending upon the size of the snaps needed to fit your backstay. This kit was just upgraded to use Top Gun sailcloth, rather than Dacron. This makes the sail hold up much longer.

Our riding sail came from Kent Sails, in Mount Clemens, Mich., and is 150 inches on the luff, 124 inches on the leech, and 62 inches on the foot (26 square feet) with seven hanks along the luff.

<img src="http://www.boatus.com/goodoldboat/images/rdsail1.gif" border=0>

Kent Sails designed our current riding sail with a fiberglass rod running between the backstay at the luff and the grommet at the clew. This rod does a nice job of stiffening the sail, and keeps it quiet in high winds. But more than that, this unusual design has the interesting feature of holding the clew out away from the backstay, in much the same way a wishbone boom on a sailboard holds the clew of the sail out from the mast. With the clew held out taut, you can swing the sail around on the backstay to point aft, which not only gets it out of the way of the cockpit, but has the advantage of putting the sail's center of effort even farther from the bow, making it even more effective at keeping the boat steady.

<img src="http://www.boatus.com/goodoldboat/images/rdsail2.gif" border=0>

If you already have a riding sail with hanks on the luff and would like to try this arrangement, it's a simple matter to modify the sail to be able to point aft. All it takes is a few feet of hollow aluminum rod, a short piece of webbing, and a couple of sheet metal screws.

First lay out a line between the luff and the clew, perpendicular to the luff, and mark where the line meets the luff. Then buy a length of hollow aluminum rod that is at least 6 inches longer than this line, and slightly smaller in outside diameter than the clew grommet (so the rod will slide through the grommet). Using your sail repair kit (you do have one aboard, don't you?) sew about 4 inches of 1-inch webbing to the side of the luff at the position you marked, with enough slack to hold the rod. (The purpose of the webbing is to keep the rod in position on the backstay.) Then cut about a half-inch-deep slot into one end of the rod so the end fits over the backstay.

The final step needs to be done with the sail hanked onto the backstay and hoisted taut. Slide the slotted end of the rod through the clew grommet, through the luff web loop, and over the backstay. Then pull the clew out taut, and mark the point on the rod where it enters the clew grommet. Remove the rod and mount a couple of sheet metal screws at that point on the rod, which will keep the clew from sliding down the rod toward the backstay. Next, cut the excess rod off about 4 inches beyond the screws.

When you now place the slotted end of the rod through the web strap, then the other end through the grommet up to the screws, and finally slide the slot over the backstay, the clew should be held out nice and taut. Finally, just rotate the whole sail aft, and add a sheet from the end of the rod to each corner of the stern rail. Using rolling hitches for each sheet makes it easy to adjust the centering of the sail. And that's it - you're done.

<img src="http://www.boatus.com/goodoldboat/images/rdsail3.gif" border=0>

A nice side effect of any riding sail is that it makes your boat easier to find in a crowded anchorage, as there aren't too many boats out there with big white triangles at their sterns. (This has come in very handy when returning by dinghy from a late evening ashore and trying to find our boat by flashlight.) Our unusual aft-pointing rig is also very sociable, in that we usually have at least one sailor in each anchorage stop by to ask about it. Last summer we even had the skipper of a nearby Alberg 30 so intrigued that he spent an hour trying to construct a similar rig using his storm jib and a telescoping awning pole. At one point when things weren't going too well and the pole fell to deck for the second or third time (there was no webbing at the luff to hold the pole in place) he good-naturedly called over, "Look what you started!"

Whether you choose the traditional forward-sheeted arrangement, or the unusual aft-pointing rig, I highly recommend you consider using a riding sail to steady your boat at anchor. Leave the "horsing around" for on shore.

Steve Christensen and his wife, Beth, sail their Ericson 38, Rag Doll, out of Saginaw Bay on Lake Huron and spend each August cruising the North Channel . . . with their riding sail.

Article taken from Good Old Boat magazine: Volume 3, Number 1, January/February 2000.

Don Lucier, 'North Star'
C25 SR/FK
<img src="http://im1.shutterfly.com/procserv/47b2cc32b3127cce92e981259d130000001010" border=0>
Cradled on the hard, 200ft from Lake Erie

Edited by - dlucier on 02/13/2003 00:24:45

Edited by - on

Arlyn Stewart
Master Marine Consultant

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USA
2984 Posts

Response Posted - 02/13/2003 : 09:25:04

Interesting stuff Don.... I think that aft of the backstay idea is really cool.

Thinking they are only partially right in the reason a boat hunts back and forth. I believe it has more to do with air foil lift than boat balance. What I mean is that the hull is a symetrical airfoil and when presented with an attitude of attack...does what air foils do...lift. Thicker symetrical foils offer greater lift so a beamer boat will likely hunt more than a narrow beam boat. Also, boats with greater freeboard (more foil surface) will hunt more.

The riding sail stops the lift in the same way a stabilizer on an airplane does, by forcing the foil attitude of attack towards nuetral where there is no lift.

An interesting way to stop the hunting would be to use spoilers that kill the foil lift...

If one wanted to test what I'm saying, I'm betting that 4 fenders with two pairs of two tied end to end as part of a sling around the hull 4-5' back from the bow might do it... Of course, its not practical because of the chaff of fenders and line on the hull...but it would prove the lift theory.

As to the evolution of riding sails... one reason they have not traditionally been used extensively is that they don't eliminate the hunting...they just control it which means the riding sail will constantly be filling on one side or the other and subject to filling noise. And, until getting used to a cyclic noises...they are torture. I spent a week in an anchorage one night with a neighbors halyards not hauled away from the mast. To become widely used, riding sails will have to be quiet.

And, riding sails have traditionally been flat sections... not very much drag until some degee of attitude of attack of the hull has been reached. So, they only reduce hunting by a percentage...though a percentage is good. I remember leaving an anchorage one night at 2am when the wind piped up and brought the combination of chop and hunting that threw me against the side of the V berth about every two minutes, a percentage would have been appreciated.

The evolution has wandered towards the V or wedge so as to present continuous drag so that the boat doesn't have to hunt a given amount before drag builds to the point of influence.

Now we are seeing proponents of balancing. That is, placing a riding sail off center so that the drag does place the boat in an attitude of attack to one side but balances it. I'm skeptical of this one.

So far...the V design looks best to me.

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

Edited by - on

Ray Seitz
Captain

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USA
416 Posts

Response Posted - 02/13/2003 : 11:35:52

I find the thought processes that you have gone through to date very interesting Arlyn. Thank you for sharing them. For what it is worth I work in a design field and I think the wedge idea, as I have stated before, has some great potential. Your comments on the noise related filling will still be present with the wedge will it not? In fact it seems as though there would also be the force of wind under the wdge from time to time trying to lift it.

<img src="http://im1.shutterfly.com/procserv/47b3df06b3127cce944032c5b1370000000010" border=0>On the hard &
Under Roof Cave Run Lake KY
Ray Seitz C 250WB #628 Sea Major

Edited by - on

Arlyn Stewart
Master Marine Consultant

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USA
2984 Posts

Response Posted - 02/13/2003 : 13:11:00

I don't think there will be any filling from under the sail... the sail tapers toward the aft and should present only drag towards the bow. This would be especially true as long as the back is not closed in and may be a good argument for not doing so as was suggested to increase awning offerings.

The pic shows what I perceive to be the front profile. The darker shading is the leach.

<img src="http://www.stewartfam.net/arlyn/frontprofile.jpg" border=0>

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

Edited by - on

dlucier
Master Marine Consultant

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Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 02/13/2003 : 13:37:57

"I believe it has more to do with air foil lift than boat balance."

I've been thinking about this and I believe that balance is the major player here.

The keel appears to be the pivot point because it provides lateral resistance in the water. For example, let's say my 4 foot fin keel were attached under the stern instead of in the middle of the boat, and I jumped overboard and pushed on the sides of the hull at the bow, then at the stern. It would seem that the bow would move much easier than the stern, because the stern mounted keel is now providing maximum lateral resistance, while the bow, with relatively no resistance, is free to move and rotate around the stern.

So if this theory is correct, a boat at anchor is acting like the C25's balanced rudder with it's pivot point being aft of the leading edge which causes the foil to turn with greater ease.

For example, let's say my boat is sitting at anchor perfectly head-to-wind when a slight wind shift from the portside acts on the roller furler or the mast, which are both ahead of the keel(pivot point). This pushes the bow slightly to port while the stern moves to starboard. With the boat pivoting on the keel, the bow now presents more surface to the wind and will now go faster to port(while the stern races to starboard), until the anchor rode stops the bow from moving. As soon as the anchor line becomes taught, the pivot point now becomes the point where the line attaches to the hull(bow). With the pivot point now the bow, wind acting on the stern pushes it back the other way only to repeat the entire cycle.

As far as the hull shape acting as a foil(providing lift because of it's foil shape), that maybe so to a very small extent, but I believe the prevailing forces acting on the boat are from the sail area presented to the wind by the hull and rigging. I don't believe disrupting the air flow (with fenders) to eliminate the foil properties will appreciatively prevent the boat from hunting because sail area has the greater effect than hull lift. For example, take a 4'X 8" sheet of plywood, which has virtually no air foil properties, but has plenty of sail area. If you were to carry it at it's center(pivot point) into the wind, it would spin you like a top. If you carry it at the leading edge, it would behave a whole lot better.

But back to the boat. Let's say we were able to completely eliminate the air foil properties of the hull through whatever means, and while we are at it, let's completely eliminate the sail area of hull, too. All that is left is the standing rigging and maybe the furled headsail to provide sail area that is presented to the wind.

<img src="http://c25c250.best.vwh.net/restricted/bro79-4.jpg" border=0>

Since both of these entities are ahead of the keel(pivot point), they will still push the boat around.

The wedge design of your riding sail is quite interesting, but more importantly than the design of the sail is the relation of it to the boat's pivot point.

<img src="http://www.stewartfam.net/arlyn/ridingsail.jpg" border=0>

Looking at your illustration, the riding sail is quite close to the boat's keel(pivot point), thereby reducing the sail's effectiveness. If it were moved a little more forward over the boat's pivot point, it would even contribute to the hunting. But if it were moved aft, it would provide more leverage to keep the boat straight.

Anyway, I want to thank you for bringing this subject up, because I'm now putting a "riding sail" quite high on my to do list, because during the season I do a substantial amount of anchoring in windy conditions and this is going to help quite a bit. Again, thanks.

Don Lucier, 'North Star'
C25 SR/FK
<img src="http://im1.shutterfly.com/procserv/47b2cc32b3127cce92e981259d130000001010" border=0>
Cradled on the hard, 200ft from Lake Erie

Edited by - dlucier on 02/13/2003 13:45:19

Edited by - on

Arlyn Stewart
Master Marine Consultant

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USA
2984 Posts

Response Posted - 02/13/2003 : 17:14:20

Don, you may be 100% right... certainly we know that its difficult to get the bow to come around in a stiff wind under jib alone.

What happens when the boat is set free to drift? It drifts downwind and usually turns a stern quarter to the wind. Probably because the boom and sail cover won't let it go straight down. So I don't disagree that the bow is trying to fall off. But...if thats all its doing, then its no big deal, it will swing around 10 feet and that will be it.

But, what takes place is the boat hunts back and forth 60 degrees or more on the rode which means it has to go upwind. What energy is being expended to cause that. I don't think its the downwind drift or stretching of the rode...

Last summer I endured the straight line winds off a thunder head. I estimated they exceeded 50 mph because of the fact that the rain drops stung my face like sleet pellets. The anchor rode was near 90 degrees to the boat.... and the sting of the rain drops was coming from 45 degrees off the bow so the boat had clawed a long way into the wind. In this case, it didn't turn to go the other way...it held there straining at the rode...

If it had been the stretch of the rode... when that energy was expelled, it would have fallen off the other way. What was holding it? I think lift and I think it was lift that got it there.

Anyway...I've got one half of the riding sail sewed and need to finish another time.

I do agree that the farther aft the drag is, the more efficient the riding sail will be. Actually, the greatest portion of the drag on mine will be towards the aft because the leach is not that far from verticle compared to the tack which has the luff and the foot falling off from it at drastic angles.

Remember however, that I'm trying to kill two birds with one stone and trying to get some awning too.

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

Edited by - arlyn stewart on 02/13/2003 21:21:41

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Arlyn Stewart
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2984 Posts

Response Posted - 02/14/2003 : 11:13:28

Have finished the riding sail / awning combo (cost $11). Have yet to build a heavier weather version of a riding sail only...but that is my next project. It will also be a V shaped design and it made from Sunbrella.

http://www.stewartfam.net/arlyn/ridingsail.html

Keep in mind that when looking at the picture, there are two sails sewn together on the luff. They wedge out at the leach with the clews directed at the stern cleats.

<img src="http://www.stewartfam.net/arlyn/79.jpg" border=0>

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

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John Mason
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Response Posted - 02/14/2003 : 13:19:36

Nice riding sail, but I'll bet that boat you've got it rigged up on doesn't swing much at anchor<img src=icon_smile_big.gif border=0 align=middle>. Seriously, though, be sure to keep us updated when you try it out. I'll be very interested to know how it works.

John Mason - Ali Paroosa
1982 - FK/SR #3290

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Arlyn Stewart
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Response Posted - 02/14/2003 : 13:53:39

Yeah...I'm in hopes that boat don't start moving <img src=icon_smile_big.gif border=0 align=middle><img src=icon_smile_big.gif border=0 align=middle>

Moving on to the heavy air riding sail... I like design that Don posted from the Good Old Boat article that extends aft of the backstay. But, I would like to modify it to a V design. Thoughts are to again use two sails and sewn together at the luffs and spread them aft.

Thinking this can be done by using either aluminum or fiberglass 1/4" shafts (think I have either on hand) sewn into the foots of each side. A spreader line between the clews will determine the spread of the two sails and lines off the clews will go to stern cleats to hold the sail centered and down.

These two sails will be much smaller and made of sunbrella.

As the article points out, the effectivness is maximum farther aft, but the design would also lend itself to use with the previous built more moderate air riding sail / awning combo which could be taken down and the more robust riding sail still flying.

Another pic...
<img src="http://www.stewartfam.net/arlyn/aftridingsail.jpg" border=0>

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

Edited by - on

Arlyn Stewart
Master Marine Consultant

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2984 Posts

Response Posted - 02/20/2003 : 21:16:15

Completed the heavy air riding sail. It uses a hybrid V design and mounts aft of the backstay per the design that Don referenced. Aluminum dowels are sewn into the two foot sections and a spreader line controls the seperation of the two clews. It is not quite as large as I thought might be necessary because I used a piece of sunbrella that I had on hand. Will test in April and let the group know how it works.

Once again, it is flying in my living room... will give pics on boat later...

<img src="http://www.stewartfam.net/arlyn/P0001806.JPG" border=0>

Arlyn C-250 W/B #224
R&R N/E Texas and Great Lakes

[url="http://www.cox-internet.com/arlynstewart/"]Arlyn's C250 Mods n Cruisin Stories[/url]

Edited by - arlyn stewart on 02/21/2003 08:06:00

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John Mason
Admiral

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Response Posted - 02/21/2003 : 15:06:48

Nice work! Looks like a great design to me. Look forward to hearing the test reports.

John Mason - Ali Paroosa
1982 - FK/SR #3290

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