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Author Topic: west country trading schooner  (Read 6131 times)

Hammer

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west country trading schooner
« on: April 06, 2010, 09:34:26 PM »

I completed this boat last year, sailed her 3 times. First and second time just drifted not enough wind. Third lucky no, would not turn into wind. I think the jibs will have to be furl led. Has anyone else had this trouble.Hammer.
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Tug-Kenny

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Re: west country trading schooner
« Reply #1 on: April 06, 2010, 09:40:21 PM »


I believe the old 'square riggers' had this problem.

Ken

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longshanks

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Re: west country trading schooner
« Reply #2 on: April 06, 2010, 09:57:21 PM »

Nice looking boat!

I'm no expert but I would be tempted to furl the two topsails. This will allow her to sail closer to the wind - therefore less of an arc to sail through to get on other tack.
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meatbomber

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Re: west country trading schooner
« Reply #3 on: April 06, 2010, 10:43:54 PM »

can you give a bit more detail on what is all RCed on your boat ? how does she look below the waterline (fin keel or not) ?
i have built 2 Brigantines (albeit small ones) and both have no problem at all heading up and tacking,  If at all then they are rather too gripping rather than having troubles heading up into the wind.

I find that sailing without the squares gave me a lot harder time tacking than with, as the squares are rather nice to have as "air rudders", but then my square sails are RCed and looking at teh pics i can`t really make out if your braces are functional.
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Brooks

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Re: west country trading schooner
« Reply #4 on: April 07, 2010, 06:27:55 AM »

If a boat won't turn upwind it's because the center of lateral resistance (CLR, the keel) is too far aft of the center of effort (CE, the sails). The opposite scenario, failure to turn downwind, comes from CLR too far forward wrt CE. Easiest solution, I find, is to move the fin keel fore or aft to get the maneuverability you desire. Small changes, on the order of 1-2 cm may do the trick, depending on how far off  balance the ship is right now. You need to move your fin keel forward to cure your "won't turn to windward" problem.

If your ship does not have a fin keel, then you could try ballasting the ship more by the head to get her to turn to windward more easily. I personally don't think models will sail well w/o a fin keel; larger models may work, but I still think they work *better* with extra keel area. Making an added fin keel adjustable fore&aft is something I design into all my vessels. I make my fin keels removable for easier ship transport to the pond.

The CE will change as you furl (or set) different sails. Thus, you can make a very quick fix for  excessive lee helm (what you are describing) by removing sails fore of the CLR, such as the flying jib. Most modelers don't like to see "holes" in the sail rig, so long term fixes of moving the fin keel may leave a more aesthetically pleasing craft.

I sail my 24" hull, 2- masted ship as a brig, brigantine, fore&main topsail schooner, and pure schooner. Each rig works great, but I have to shift the fin keel to regain balance between sails and CLR for each rig change. I also sail a 4 masted barque (3'hull), and a topsail schooner bottle boat. All needed experimentation with the fin keel placement. All my ships can tack and wear, and I am sure yours will too.

There is a learning curve associated with RC square-rig operation. If this is your first squarerigger, you might find John Harland's "Seamanship in the age of sail" book useful. I consider it the bible of square-rig operations, and have seen it consulted by crew when sailing aboard full size square-riggers.
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Hammer

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Re: west country trading schooner
« Reply #5 on: April 07, 2010, 02:09:14 PM »

More information as requested. 3 ft at the water line by 8ins beam and 4ins draft. No fin keel , ballast cement mixed with lead chips. stability is no problem as a section of the lead keel drops down when the carrying handle in the hold is let go. It drops 4ins at the present which is to much, as she bobs like a cork. Fitted with 5 functions rudder, fore sail sheets, rear sail sheets, square sail sheets and scandalising square sail almost furling. See below. I did try to move the center of effort back,at the pond but one sail was insufficient. the extended rudder was no help ether. I will try the rest of the jibs next time we have a strong wind and sunshine. Thanks for your information. Hammer.
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Brooks

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Re: west country trading schooner
« Reply #6 on: April 07, 2010, 02:49:44 PM »

Very beautiful ship, Hammer! I hope you can post more photos and videos of her sailing.
-----------
Squarerig modelers have to make a decision: Do I want realistic sailing or do I want a realistic hull? For sailing, a finkeel is necessary if you want to work to windward. I think a lot of the bad sailing reputation of square rig models is due to the builder eschewing a fin keel. Water does not "scale", and the modeling scale factors work against us: a 1/2 scale model, for instance, has 1/4 the sail area and 1/8 the hull volumn of the real ship; smaller scales are even worse off eg. 1/40 scale has 1/1600 the sail area and 1/64000 the hull volumn. Thus, we have to compensate with extra keel area. My ships and their finkeels will work to windward w/o problem, albeit at a lower angle than a sloop. Since it can be removed when the ship is on the mantle, the finkeel need not destroy the lines of the hull. In the waters I sail (fw ponds), the fin keel is usually not visable due to reflection, refraction, and waves.

I've sailed my barque with fin keels of 7, 10, and 14" width, all about 12" depth. The 10" wide one works the best on my 3 foot hull. The 7&14" are made from 1/4" plywood, the 10" from 11/16" birch plywood. To attach the finkeel, I screwed a 1x1" Aluminum angle  to the bottom of the hull. The finkeel bolts to the Al angle. Drilling new holes in the Al to allow different keel locations is easy. Wide finkeels are necessary (compared to footy's and other racing sloops) because squareriggers move more slowly and because there is much more windage aloft due to spars and rigging.

There is about 1.5kg of lead shot ballast in a pvc pipe attached to the bottom of the finkeel. It is very difficult, if not impossible, to achieve realistic sailing model stability with internal ballast. For my barque, it would take 18kg of internal ballast to equal the righting moment of 1.5 kg external ballast on a 1 foot deep finkeel. I doubt my hull would float 18kg of ballast.

While a finkeel won't stop bobbing, it will slow the roll rate, making for a more realistic motion in that plane. This is particularly evident with Aldebaran, which has a 20" deep keel. This is due to the area of the keel. There is also a lengthening of pitch period, due to the weight on the end of the keel, though that effect is not as evident, to me, as the lengthening of the roll period.

Build and sailing commentary threads for my models (with urls to the videos):
Barque Pamir (started as a free-sailer, but converted to RC):
http://www.rcgroups.com/forums/showthread.php?t=743611
Topsail schooner Aldebaran:
http://www.rcgroups.com/forums/showthread.php?t=1096365
Bottle boat topsail schooner:
http://www.rcgroups.com/forums/showthread.php?t=1071509
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Brooks

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Re: west country trading schooner
« Reply #7 on: April 07, 2010, 03:14:03 PM »

Hammer, your furling system is really neat. I hope you will post some more photos and description of how you achieve this.

Clewing-up/down won't do much for changing the CE favorably, though. The clewed-up lower topsail, and clewed-down upper topsail, will still generate a lot of drag (windage). You'd have to actually furl them to get a benefit, CE-wise. Clewed-up/down they will reduce knockdown, though, just as with real ships' sails. And of course they add a unique feature to your vessel, Well Done!
---------
Rudders are more for persuasion, than for control, of a multi-masted ship. The forces on the sails will overpower rudders almost every time. Thus, if your ship is not balanced, sail CE vs hull&keel CLR, no amount of rudder will fix the problem. Rudder extentions, as I see you have installed, are good, and necessary - a scale rudder will suffer the same scale effects as discussed above. Once the ship is balanced, then the rudder will have an effect, allowing you to tack and wear.
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meatbomber

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Re: west country trading schooner
« Reply #8 on: April 07, 2010, 05:02:06 PM »

Another thing that migth prevent you from heading up is if your yard angle is too small, then teh tops'l backwinds very early and the drag it creates is enough to prevent the head from coming up, it`s basically heaving to. can you make some pics with the squares braced at the maxiumum angle ?

and i concur with brooks it`s an outstandingly good looking ship :)
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Jimmy James

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Re: west country trading schooner
« Reply #9 on: April 07, 2010, 08:54:25 PM »

You might just try this
1) Fall off the wind a point to allow the speed to pick up 2) Put your helm up, let fly your head sails, haul your main in hard and brace up your yards, 3) if she comes through the wind the square topsails should A) get back winded and push the head around... in which case ...sheet home the head sails and slack off the main Brace the yards round on the new tack  B) the vessel misses stays and starts making sternway ... Reverse your helm ...85% of the time the vessel will back herself on to the next tack...
  Adjustments that help   1) Try raking the masts aft 2 or 3 Deg.... 2) increase the length of the main boom and add a section to the foot and leach of the mainsail (a triangle of cloth extending only the lower half of the main) this will  shift the centre of balance aft a wee bit and should help her tack.
 It is not unusual for a vessel to be a bit hardmouthed and a lot of topsail schooners were renowned for it and only used the square sails on a long passage ...............A bit of tweaking can often cure this... But on some ships you often just have to SWEAR & WARE... Hope this helps a bit ... But whatever keep trying,.. It might be finger trouble
Freebooter :-))
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tigertiger

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Re: west country trading schooner
« Reply #10 on: April 08, 2010, 01:38:51 AM »

Hi Hammer

You say you have no fin keel, but section drops down below the carrying handle.
Can you explain/show this section please?

If it is acting as if it was a fin keel, this could be part of the problem.

Could we also see a photo of your rudder please?
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Hammer

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Re: west country trading schooner
« Reply #11 on: April 08, 2010, 10:18:28 AM »

The pictures should explain how the drop keel works. The rods top 1inch has a larger diameter and the slide tubes narrower at the bottom to prevent the keel dropping right out. Sorry about the rats nest in the hold this is a small box containing the resever and all the connectors. I wish it was finger trouble, I have no problems with my other sail boats, pictured below. Finally the rudder extension. I do realise the full size ships steer by the sail, and only fine tune with the rudder but we have to cheat a bit. Hammer.
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Re: west country trading schooner
« Reply #12 on: April 08, 2010, 10:45:11 AM »

Hi Hammer

A lovely collection of boats.

Interesting keel set up. That is a new one for me.

Can't see the rudder extension though. Might be because you can only attach 6 pics per post.
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Hammer

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Re: west country trading schooner
« Reply #13 on: April 08, 2010, 10:53:09 AM »

Sorry Tiger I forgot to load it!!Geoff
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Brooks

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Re: west country trading schooner
« Reply #14 on: April 08, 2010, 03:10:15 PM »

Very nice fleet, thanks for posting!

I do realise the full size ships steer by the sail, and only fine tune with the rudder but we have to cheat a bit. Hammer.

I feel it's the other way around :-). Models have to conform more to "physics" than real ships since we can't cheat as easily. The low Reynolds numbers in which models operate, compared to real ships (and planes), has been suggested for some of the differences, but please don't ask me to explain, because I am still working on understanding. Models sail in a more "molassas-like" environment than real ships. This works to our advantage when we use the model rudder to scull. You can scull home in a calm, something a real squarerigger could never do (they'd use sweeps, ie oars). I have also use sculling to complete a failed tack in light winds, again, something impossible to achieve in a real square rigger. So, in certain circumstances, the model rudder works better than the real rudder. But for regular maneuvers of my ships (all of which have increased rudder area compared to the real version), the model rudder is not the controlling force, rather it is the sails which control the ship's course. For consistant tacking and wearing I have to get the CE and CLR fairly closely alligned before the rudder will make the ship follow my orders.

While a single-masted model ship may sail a straight course of the skipper's choosing with the rudder hard over (to correct for inbalance, eg. my sandbagger on a run), the multimasted ships that I sail simply won't work that way. I always start my maiden voyages on a lee shore because, until I get the finkeel positioned correctly, the model may not turn around to come back.  I've had to chase models on their maiden when I misjudged the finkeel's position: they ignore the rudder and can neither tack nor wear, hoho. In a case like this, I'll slack the sheets and let the wind push the craft w/in reach for field adjustment and another attempt. Or, I'll use differential sheeting (as mentioned by Jimmy James); to turn the boat downwind, slack the sails aft of the CLR, allowing the still-drawing sails fore of the CLR to push the bow downwind.

Getting new multimasted sailors, those used to horsing around their singlemasted models with rudder, to accept the idea that the power of sails>>the power of rudder has been a struggle on other threads where folks ask "why doesn't my ship sail right?" :-). However, racing skippers immediately accept the concept because they know that winning skippers use as little rudder as possible. They know that every rudder command steals some speed. For ships, every loss of speed diminishes the power of the rudder; it's quite easy to get in a losing situation with multimasted ships.

This shows up with square riggers trying to tack, where the sails are actively trying to stop the ship once she is near head-to-wind and the squares are backwinded. At some point the rudder becomes useless; reversing your helm when the ship starts to drift backwards is a very useful and effective way to tack; it's called "tacking with a sternboard" and was used by real squareriggers.  I use it all the time when I've misjudged the sail area to set for a cruise. Weather conditions, coupled with sail choice, play a big part in successful model square rigger sailing. Too few sails, and you are too slow for effective rudder; too many sails, and the ship heels too much for effective rudder.

Jimmy James has some very good advice on tacking. His informative post reminded me that operator error can foil the best balanced ship, and that the operator skill can overcome some ship deficiencies.
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Hammer

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Re: west country trading schooner
« Reply #15 on: April 08, 2010, 04:58:52 PM »

Thank you all for sharing you hard earned knowledge. Will let you know how I get on next time out. Yes Brooks I had the experience of too big a rudder with my first pilot cutter. She would get stuck in irons and I had to waggle the rudder to get her around. Increasing the rudder size made things worse. So back to the original size and drive her into the turn. No problems. As you mention speed may be a large part of the problem I'm having. Also the club pond (you would call it a puddle in the U.S.) has a lot of trees around it they don't help at all. HAMMER.
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Brooks

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Trees
« Reply #16 on: April 08, 2010, 06:35:37 PM »

Trees around a pond - Shiver those Timbers, Chop'em Down! They are one set of foliage I won't hug :-)

About the only conditions my squareriggers can't handle (and a lot is due to their skipper) are flukey light winds. Trees mess up wind flow, and in light conditions are a real menace to making progress to windward. A fore&aft boat can make good a course 4pts (45deg) to the wind. But a squarerigger is doing well to make 2 pts, and 1 pt was the limit of the older real squareriggers. On a given leg, a squarerigger will only get half as far, at best, upwind as a sloop. Every time the wind veers or backs as you progress on a beat, you need to tack, as racing skippers know. But the detection of small wind direction changes is difficult as the ship goes offshore. I've had lots of cruises where the wind switch was not detected (by me) and the ship has lost ground. Or, by the time I started to tack, the wind had switched back and I either missed the tack, or ended up sailing backwards - squareriggers are easy to sail in reverse, whether you wanted to or not :-).

The phrase "back and fill" was used to name the process of zigzagging up wind in a narrow channel - the ship would not tack, but, when reaching  the limit of usuable channel,  would swing the yards to backwind the sails. The backwinded sails would make the ship go backwards, and if the yards were oriented properly, she would sail up wind backwards. I have read an account of a clipper ship that did this in the China tea trade, but I forget the Chinese river name.

Boxhauling, a form of tacking+wearing, uses this ability of a squaresail ship to back into the wind when all sails are aback. It's a method I use to save a failed tack; it loses more ground than a normal tack, but less than a normal wear. There are some diagrams of the method over on the Pamir thread, drawings taken from Harland's book.

My normal sailing and flying pond (float planes) is in a new housing subdivision. The homeowners council decided to plant trees around the pond, the blighters. They have not yet grown big enough to blanket the pond (like my other sailing/steamboating site). But they do affect the wind currents, and are an obstacle to RC float planes - my friend's son caught his Citabria floatplane up in a tree one afternoon; it's only a matter of time before I do the same :-).
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Greggy1964

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Re: west country trading schooner
« Reply #17 on: April 09, 2010, 12:39:53 AM »

I'm following this discussion with interest as my Master Hand build (when I finally finish it) presents me with the same issues, though I imagine it will not be as difficult to manage as a square rigger.

I haven't sailed anything out side of 'stock' single masted stuff which is a 'breeze' (scuse pun!) compared to this stuff but much more fun as it challenges the captain to operate his vessel in a ship shape manner. :-))

I've always fancied the idea of a huge scale model of an Elizabethen Galleon since I was a kid but have been put off by their poor performance as a scale model.
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Brooks

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thoughts on an Elizabethan Galleon
« Reply #18 on: April 09, 2010, 06:41:31 AM »

Elizabethan ships would not pose an insumountable problem, if you make a few modifications, I think. The problems are 2-fold: a) lots of windage from the 1500-1600's era fore and stern castles, and b) low efficiency sails. This will make progress to windward difficult to achieve if the ship is built exactly like the real ones. But, there are things that you can do to surmount the problems that will not greatly detract from the appearance of the ship. If you don't care about sailing to windward, then build your model just like the real ships. I am biased toward windward performance, or perhaps more accurately, biased towards not having to walk to pickup my model, but rather have her sail right back to the starting point :-)

I'm both a sailor and a pilot; I find explaining the forces on a sailboat easiest to understand if I treat them as lift & drag forces, like the forces on an aircraft. This approach is not the traditional one used by shipwrights, though I've seen websites for racing sailors and yacht designers using the aero terms. Hopefully my terminology won't pose an excessive obstacle to understanding.

Wind speed requirement:
Windage (drag of the wind) from exposed hull will make progress to windward difficult. The tall castles on early ships is an impediment, no question. My bottle topsail schooner has a lot of windage since the bottle provides much more buoyancy than is needed to support the rig and RC gear. 3/4 of the hull rides out of the water - adding more ballast to sink the hull to a more realistic freeboard would make the boat very heavy. However, even with a lot of windage, she beats fine in a strong wind; With enough wind, the sails generate enough lift (=force) to make the ship speedy. In that case, the finkeel develops a lot of lift, combating the tendency of the hull to simply blow downwind. So, the first requirement for working to windward is enough wind.

Low wing-loading keel requirement:
The more surface area in the finkeel, the lower the lift/unit area  needed to generate enough lift to keep the boat from drifting downwind. With a low enough wing-loading finkeel (=big finkeel), the ship will perform satisfactorily in moderate breezes. Any ship with a lot of windage will benefit from a large finkeel. Thin width (chord) fin keels, used for footys and racing sloops, have a high wing-loading. As a result  they only work well if the ship is fast - since these boats are speedy, though, they can use high wing-loading keels. Squareriggers are going to be slower than racing sloops, usually, so they need a low wing-loading keel. My first keel for the bottle topsail schooner had a footy-sized chord. It failed miserably. My 2nd was about 2x footy chord, and it worked better, but still not well enough to make reliable progress to windward. The final finkeel design, which works well, has a chord of about  80% of the length of the hull, and a depth about equal to the hull length; that's a lot of surface area, more than most modelers normally see, I'd guess. A keel this big has a lot of surface drag, so the ship will not be fast in light winds, however. The 2nd requirement is a big enough finkeel.

Flat sail requirement:
Baggy sails don't work well when you are trying to beat. At the low Reynolds numbers our craft operate at, a flat sail (=low camber airfoil) works better. The paintings I've seen of Elizabeathan ships show baggy sails. If you want your ship to work to windward, though, you will probably have to replace the baggy sails with flat sails. My ships have sails made from Tyvek - it's easy to work with, sheds water, and allows flat sails. As a side note about real ships: It's easier to make flat sails out of cotton canvas than out of flax canvas. One of the advantages the yacht America had over it's British competetors in the famous race was the flatness of the America's cotton canvas sails. The 3rd requirement for a Galleon is flat sails.

If you can live with a big finkeel, flat sails, and choosing to sail only on days with enough wind, an Elizabethan ship model should sail to windward fine. She probably won't ever do as well as a lesser windage hull, but I think, based on my high-windage bottle boats that the Galleon should still provide fun sailing (w/o walking).

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Jimmy James

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Re: west country trading schooner
« Reply #19 on: April 09, 2010, 09:22:37 PM »

Greggy1964
 If you look in the thread Brigantine Freebooter under sail (Yachts & Sail --R&D) you will find some photos of the Privateer Barque "Fire Drake" under sail in a mid 1600's rig Showing both her test rig and her finished rig... she is fully R/C and sails quite well.... Freebooter is also fully R/C and has no fin keel and is a superb heavy weather sailer when reefed down.
Jimmy
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Jimmy James

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Re: west country trading schooner
« Reply #20 on: April 09, 2010, 09:59:43 PM »

Hammer
 If you look in the thread "Rigging Tool " You will find some pictures of "Wyvern" topsail schooner under sail ...She was at first a bit hard mouthed but I added an inch and a half (150mm) to the main boom and now a child could sail her .... sorry I don't have any pix of her with the square tops set but you might like to know the braces for the yards run forward to the bowsprit  {:-{(Cutter Fashion) then aft along the deck to the winch--- Not aft to the mainmast when down to the winch  :(((square rigger Fashion) This allows the fore sail to be free from interference from the braces and gives better sail control. :-)) :-)) Wyvern also has NO fin keel but her keel has been extended a little  ...She's 44" LOA with an 8" draught
Jimmy
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Re: thoughts on an Elizabethan Galleon
« Reply #21 on: April 09, 2010, 11:55:33 PM »

The final finkeel design, which works well, has a chord of about  80% of the length of the hull, and a depth about equal to the hull length; that's a lot of surface area, more than most modelers normally see, I'd guess.

 :o

How does she steer with so much fin?

Andy
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Brooks

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Re: west country trading schooner
« Reply #22 on: April 10, 2010, 11:37:24 AM »

The bottle topsail schooner seems to steer fine with the big fin. You can observe tacks in heavy wind in one of the videos. The boat zips to the other tack w/o any problems. I was sort of surprized at this, expecting a loggy boat, but that did not happen. I don't sail this boat in low winds, though; she has an insufficient sail area:windage ratio. My bottle sandbaggers sail fine in light winds; sandbaggers were notoriously over-canvased :-). Those sloops, btw, have narrow chord finkeels, about 2-3x footy width. They are high freeboard/high windage boats, but there is plenty of sail thrust to compensate - their speed makes their narrower chord keels generate sufficient lift.

Note the bottle topsail schooner's rudder extention; a deep narrow chord rudder did not work well (with any keel); I had to widen the chord to get acceptable turns.

My Pamir has had 3 keels. The narrowest chord keel (which is now the bottle boat's) and the widest chord keel did show some differences in Pamir maneuverablilty. But even the widest keel (chord=38% of hull length) did not hamper maneuvers, rather it just made them slower and more realistic, to my eye. This wide keel had more ballast too, so maybe the extra inertia was helping complete tacks.

But, maneuverablity is certainly a consideration, to be balanced against ability to work upwind at a good angle. Older models (from 1890's) have longer keels than more modern models, at least in the plans and photos I've seen. They were not RC. In addition, contests of that era, at least in Britain, valued keeping on course, to hit a targeted harbor for max points. I like my squareriggers to look realistic, and a steady course w/o excessive weaving, adds to the illusion of a real ship, to me. I won't accept poor tacking, though, so the ship has to be able to turn well enough to complete tacks (and wears).

Your sailing conditions may influence your keel choice. If you have steady breezes w/o tree interferance, then working to windward is easier than under flukey, swirly winds. For steady breezes and easy progress to windward, a narrower chord keel may be fine. For the challenging conditions, where every foot gained is important, then the wider keel may serve you better. There is no law against having mroe than one keel, and choosing the one to attach based on weather. I did this with Pamir, until I finally decided the 3rd keel was an acceptable compromise. I started thinking the narrow would be good for light airs, due to less surface drag, but found that the leeway was too great. So, my procedure developed to narrow=highwinds, wide=lowwinds. My 3rd keel has an inbetween chord, and, along with it's nice airfoil, works better than either of the 2 earlier models.
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JayDee

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Re: west country trading schooner
« Reply #23 on: April 10, 2010, 11:56:44 AM »

Hello Brooks,

Lots of good information, thanks for the posts.
My schooner has a 72 inch long hull, the keel is 14 inches long, 8 inches chord, aero section.
I am able to lower it by 2 inches for sailing in high winds, which really helps.
The centre of the keel is placed at the "CLR" of the hull, not movable at all.

To help tacking in very high winds, I pull IN the mainsail, to help the boat to pass through the wind.
Because of the higher boat speed in these conditions, sheeting ALL the sails in during a tack also helps.
Sheet the sails out again when the tack is completed.

John.  :-))

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Brooks

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Re: west country trading schooner
« Reply #24 on: April 10, 2010, 08:33:28 PM »

Thanks, John. You're magnificent Bluenose has been an inspiration to me, and many others, too, I am sure.

Some more model schooners:
http://matthewsmodelmarine.wordpress.com/writings/2005-vintage-traditional-watercraft-regatta/
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