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  #1  
Old 10-28-2006, 02:00 AM
jack wicks jack wicks is offline
Wicks
 
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Want to build modified Tancook Whaler

Hi, I'm a new member so take it easy on me . I work in the aluminum power boat manufacturing industry. We build jetboats, outbrds, etc., from 17' to 26' so I'm comfortable working with aluminum and prefer it.. I'm in love with the Tancook Whaler style schooner. I would like to keep it small, say 24 ft. bow to stern and built with a V bottom. We sail on the Snake and Columbia River in Wa. State which is very shallow in some areas. Are Twin center board keels better or worse on a boat of this design? I'm Tired of sailing with overlaping sails, especially on the slackwater rivers which are usually less than a half mile wide. (Love them schooners)
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  #2  
Old 10-28-2006, 06:47 PM
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Twin centerboards offer no distinct advantage in a boat of that type. Twin bilge keels can, in that area of the country, as tidal ranges can be quite large and finding the bottom very likely (planed or unplanned). With bilge keels (twin fixed fins) the boat can take to ground and stand upright until the tide returns and floats you off. A properly designed centerboarder can do the same thing, using one of a few different tricks to keep her from flopping over on her flanks excessively, at slack tide.

The schooner you desire is traditionally a "built down" hull, with lots of burden and hull below the LWL. A shoal draft version will be a difficult stretch for that design. From the LWL up, she can have the look of the old whaling schooner, but below the LWL and likely her beam will need modification to get shallow water ability, not to mention the appendages.

The schooner rig is pretty and fun to sail, but a real bear to short tack up narrow rivers or maneuver in crowded places. Even with a self tending rig, she'll be slow in stays and not particularly close winded (typical of all divided rigs). Schooners are happier in open water with plenty of sea room to work with. A small, shoal version is an interesting set of designs issue any designer would love to tackle. A set of stock plans, given the specific design parameters, will be difficult to find, so a custom or modified plan may be your only choice.

I have experience with shoal draft, aluminum sailboats, intended for your area, if you'd like to drop me an email.

Ricelli's Aluminum Gift
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  #3  
Old 10-29-2006, 12:30 AM
jack wicks jack wicks is offline
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Par, Thanks for the come back, You are pretty much on target of what I'm thinking also. I guess I'm pretty much a throw back in time romantic when it comes to Schooners. I'm more interested in the sail plan of the Tancook Whaler than I am the hull design, especially for our area. We don't have a tide problem here, (300 mi. inland approx.) but we do have a lot of silting etc,. We do have a lot of really great lakes within a 150 mile radius to sail on. This means Trailering would also be desirable. I've done quite a bit of racing etc. with the local sail clubs , but am more interested in fun and a relaxed sailing approach, also pleasing and different to look at. ( everyone around here says I've lost my marbles for wanting a schooner, maybe so ) Have lots of ideas if anyones interested, Thanks again. Wicks
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  #4  
Old 10-31-2006, 09:00 AM
sharpii2 sharpii2 is offline
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Dear Jack:

The most important question is how much draft can you tolerate. According to my Chapelle book, A Tancook boat of your size would have a draft of three and a half to four feet. Plus, of course, the center board.

It would be interesting to design a dory that had a similar above water profile. The two top side plates would have a great deal of twist to them and, therefore, have to be multi conically developed. The width of the flat bottom would be nearly the same as the over all Beam. There, you could put twin keels to get your shoal operating draft as well as avoid dividing the already tiny (six foot wide) cabin with a centerboard case. The draft using this scheme should be no more than 20 to 24 inches

A long 'drag keel' (one that has its bottom edge slope continuously downward as it as it goes aft) may be less of an impediment to trailering than one might imagine. It may even facilitate the job by, first, being much shallower in the bow than in the stern, and by, two, having a continuous straight edge to guide the boat onto the trailer. The long drag keel would also make a formidable girder to strengthen the hull. The draw back to this is that your upwind performance will be, shall I say, modest. If you got 100 deg. tacks, I would say you would be doing quite well. A good engine of modest power (the original Tancooks were rowed) would get you out of tight spots until your 'schoonering technique' improved. The draft, using this scheme, should be roughly the same as the twin keel version if not a little less.

The drag keel version would be much slower in coming about than the twin keel one would be. That is where backing the jib, to force the bow over, comes in (schoonering technique).

Bob
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  #5  
Old 11-01-2006, 01:32 AM
jack wicks jack wicks is offline
Wicks
 
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Sharpii2
Thanks for the reply,, You hit the nail right on when you talked about building a Dory style hull with twin swing keels to keep the center of the cabin floor open. I was thinking of building in a small amount V ,say 14 to 16 degrees in the bottom to help with lower C.G. and keep anchorage noise, ( pounding) down. I'm thinking of twin swing keels of 1" steel plate 4 to 6 ft. long. Also maybe having the keel wells permanently exstending below the bottom approx. 6" . ( Need to draw picture ) ,. A swing up rudder is almost a must in this area, also a rather short turning radius around here is a real plus. I'm thinking of a beam width of 8 to 8.5 ft. , Deck length of 24 ft. approx. and a small bow sprit of 4 to 5 ft. A 6 ft. or 5.5 ft. wide cabin would be OK.. I was planning on putting about a 10 degree bend in the center of the sides, full length, with a rounded slope backed transom. Do twin keels need to be towed in at the front??

Thanks again,, Wicks
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  #6  
Old 11-01-2006, 10:08 PM
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PAR PAR is offline
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The "V" bottom hull is much superior to the flat bottom form. Even the best dories were multi chined craft, which presented a well shaped entry to the bow wave. The classic flat bottom dory was at it's best when it's chine had some bury and the boat sailed flat footed. I would strongly advise a "V" bottom design over the flat, presented with a choice. The flat is a simpler build, but not that much more so. The "V" will have a bilge and provide a place to hide most, if not all of the centerboard case(s), which the flat bottom boat would be hard pressed to do without stub keels.

The schooner is a wonderful rig to look at, but has the worst windward ability of all the divided rigs. It has loads of reaching power, but is limited by luff height in the headsails and foresail. Modern interpretations of the rig have increased the luff of the foremast to mainmast height, which has helped, but the romantic look is gone, appearing as a ketch with an oversized mizzen.

I have a 25' "V" and flat bottom design that may suit your needs. It currently is designed as a centerboard ketch, but could tolerate the change to schooner if you are just bent to own one. The "V" boat is a near shore cruiser and the flat is a protected waters day boat. The flat has a sharpie style transom (rounded) and the "V" carries a traditional curved transom, but could be redrawn for a rounded or fantail stern.

Much drag to the keel makes support on the trailer troublesome. A little drag is good and she'll lie too nicely, when reasons insist. I would also recommend a "3/4" keel rather then a full version. It permits crisp maneuvering and good tracking and separate rudder(s) for the same reason.
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  #7  
Old 11-02-2006, 09:31 AM
sharpii2 sharpii2 is offline
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Light Schooner

Maybe you ought to look at Phil Bolger's 'Light Schooner' design. It has no keel at all, but a dagger board instead. It is flat bottomed with a slightly raked transome. It is 23ft 6in on the deck and 5ft Beam. It is designed for plywood construction, but, with your experience with Aluminum, it should be little trouble converting the plans.

There is a write up about it in the Nov/Dec "WoodenBoat" magazine if you want to know more about it. On reaching conditions, it is said to be screemingly fast. It is also a pretty boat in profile. Check it out.

Bob
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  #8  
Old 11-03-2006, 12:27 AM
jack wicks jack wicks is offline
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Thanks Bob, I'll Check it out, It's pretty hard at times to even find the ,Wooden Boat , mag. in this town. The mag. racks are pretty well full of nothing but p.u., cars, and motorcycles,. Sometimes I think I'm stuck in the wrong area of the U.S.. Thanks again, You Guys are really helpfull. wicks
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  #9  
Old 11-03-2006, 12:50 AM
jack wicks jack wicks is offline
Wicks
 
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Par,
Thanks for the reply,, I may e-mail you and see if I can exchange some schetches etc.. also would like to see something on your 25' V bottom boat.

I read your POSTS on, Where are all the Wreaked boats,. Very interesting, you answered a lot of questions.
Thanks ,, Jack
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  #10  
Old 11-03-2006, 08:14 AM
sharpii2 sharpii2 is offline
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Quote:
Originally Posted by jack wicks View Post
Thanks Bob, I'll Check it out, It's pretty hard at times to even find the ,Wooden Boat , mag. in this town. The mag. racks are pretty well full of nothing but p.u., cars, and motorcycles,. Sometimes I think I'm stuck in the wrong area of the U.S.. Thanks again, You Guys are really helpfull. wicks
What?

No WoodenBoat?
This is a humanitarian catastrophe.

Send the air lifts imediatly.

Seriously. I will cut that article out of WoodenBoat and send it to you if you like.

Just 'private messege' me with your address and I will send it to you.

Bob
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  #11  
Old 11-08-2006, 11:44 PM
jack wicks jack wicks is offline
Wicks
 
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Sharpii2

Thanks, for the offer, . Alls well, I found a Wooden Boat Mag. in town. I seen the article on the Scooner. Looks interesting but , I don't think I could get my wife to stay overnight on the water, let alone make coffee on board. Not that you couldn't,. Liked the design though and it does go real well I bet.. Wasn't there a longer folding version of this boat also? I see Atkins has a 23' schooner that looks interesting also. Thanks again,

wicks
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  #12  
Old 11-07-2010, 03:30 PM
Kilisut Kilisut is offline
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Tancook Options

I know it's four years later; but in case you haven't done this project and are still interested, here's some ideas. I take it you're in love with the rig. Well and good, it's very pretty. The drag of the keel, and consequent draft are closely linked to it. Hard, but not impossible to have one without the other. Before centerboards, schooner boats and cat schooners were very common in colonial North America, they were generally faster and closer winded than ketches of similar proportions (see Bolger "103 Sailing Rigs); even in Great Britain small luggers of the period were frequently cat schooners.

When centerboards were introduced, they were logically placed between the masts. In order for the relationship of the center of effort (CE) to center of lateral resistance (CLR) to be correct, the rig was changed to ketch or cat ketch, otherwise the CLR was too far forward with the schooner rig, and weather helm became excessive. The extreme drag of keel of the Tancook model counteracts that, and the centerboard is relatively small, and placed as far aft as possible, immediately forward of the mainmast, and not extending to the foremast. Mind you, it's not always that deep. Taking a survey of the designs in Posts "The Tancook Whaler" and checking the proportions of length to draft, your 24 foot boat would have a draft of between 28" and 36", with the board(s) up.

If you need very shallow draft, there are other ways. Set the centerboard case on one side of the centerboard case, and the mainmast on the other. This was commonly done in three masted coasting schooners, and enables a relatively level straight keel, with little or no drag required. You mentioned twin centerboards (AKA Bilgeboards), leeboards are also possible. In either case, they are out of the way of the mainmast and you can have a straight, level keel with shallow draft.

Don't bother toeing in the boards. Bolger claims you'll always overdo it. Making them asymetrical foils could work. Don't make them out of inch thick steel though, too heavy, and will require hugely strong and heavy structure in the cases, which are not good places for ballast. Put the ballast in the bilge or center keel, where it does the most good. If you have the room, you could put it between the bilgeboard cases and the sides; in that location it will slow the rolling period. Spreading out the ballast athwartship has this effect. Deep ballast is not needed for sail carrying or self righting. Sail carrying can be achieved by form stability, self righting by appropriate location of reserve buoyancy. Get a good designer for this.

I will offer a shape idea. This is a vee bottom concept I've seen in at least two of Phil Bolger's designs, one in aluminum, one in plywood. The essence is that the keel rabbet (seam where bottom strakes attach to the keel, a welded joint in the case of an aluminum boat) is straight and level for most of it's length, the area of the bottom between the straight rabbet section and the middle of the chine at it's lowest point is a perfectly flat triangle, with no shape or curvature. Fore and aft of this the ends of the bottom curve up to meet the rest of the chine, keel, stem and stern. It works best with a boat that is relatively narrow. In your case, not more than 8 feet of beam. It is ideally suited to aluminum though. The deadrise amidships can be as little as zero, dead flat horizontal. That gives you the most displacement/floatation for a given draft. The deadrise is in the ends, where it fairs the water flow, and looks good.

A shallow rudder can work well with an endplate on the bottom of it, Bolger uses this a lot.

Oh yes, Tancook Whalers are double ended. I don't know why you mentioned a transom. I always think a pinky stern, with the little tombstone connecting the extended bulwarks around the rudder head is very nice to look at; and if the top is high you can notch it and use it for a main boom crutch.
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  #13  
Old 11-10-2010, 11:19 PM
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BATAAN BATAAN is online now
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Tancook Whaler was a light/medium displacement half-decked "boat", and not the heavy vessel some on this thread seem to think. The originals were lapstrake and even the larger carvel ones had very thin spruce plank, light bent frames and a minimum of anything else. Their light masts had a single shroud a side and a single headsail. Part of their excellent performance was the overlapping foresail, so not a good idea to change that if you want good sailing.
The steep raking ends make for an extended waterline when heeled, as well as picking her up in a bad seaway if you keep them empty and light.
Just copy the original with its centerboard, a v-shape is fine if it closely approximates the original lines, sitting head room in the cuddy, a big open cockpit, the large original rig and you'll love it.
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Old 01-03-2011, 12:25 AM
jack wicks jack wicks is offline
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Tancook Whaler Kilisut

Thanks for the reply, I haven't built the boat yet. Still planning to though. I'm still working for an Aluminum boat manufacturer so aluminum will be my choice. Still wanting to build a modified tancook whaler with a v- bottom and transom style, sort of a classic old style look if possible. Want to do away with centerbrd trunk, but keep the draft as shallow as possible.
Thanks , Jack
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Old 01-03-2011, 05:44 PM
Kilisut Kilisut is offline
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Tancook Whaler

Correction to my first post. In three masted schooners the centerboard case was on one side of the KEEL and the mainmast on the other (I had put in centerboard case a second time instead of keel).

Anyway, why a transom? One of the definining characteristics of Tancooks, and part of their beauty is the sharp stern (double ended hull).

By "do away with the centerboard trunk", do you mean, entirely, or just get it out of the middle of the boat? There are a couple of options such as tandem boards, with a big one aft under the cockpit and a little one forward, which leave the cabin clear. There are twin bilgeboards, sort of like inboard leeboards in trunks that leave the center of the cabin clear. In a Tancook as small as yours, the traditional board in the cockpit in the middle of the boat with a small cuddy forward to keep gear dry and a private place for the porta-potty works. There's Bolgers favourite, leeboards, of one sort or another. See "Boats with an Open Mind" for his favourite way to hang them. With a V-bottom there's the option of shallow twin keels, possibly with end plates. There's also a single off center centerboard with the case forming the front of one of the berth/setees on one side.

If I was building an aluminum Tancook for shallow water (the originals were for deep water, the centerboards made them easier to row and handle better off the wind) I'd use a shape like Bolger's pulling boat "Crystal" and the ketch "Wolf Trap" from "Different Boats", but with a dead flat bottom amidships instead of the deadrise he uses, rising to V-bottom at the ends. I'd put a centerboard next to the mainmast on the opposite side of the keel from it and keep the cuddy cabin small and forward. And follow Tom Colvin's advice about epoxying and installing spray in insulation in a metal hull, condensation in a metal hull is tedious.

If I was building a Tancook for VERY shallow water I'd use the same shape, but use leeboards instead of any kind of centerboard. They don't have to extend beyond the bottom of the keel to be effective.

Glenn
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