Want to build modified Tancook Whaler

[jack wicks]

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)

[PAR]

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.

http://www.boatdesign.net/forums/showthread.php?t=10388&highlight=ricelli%27s

[jack wicks]

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

[sharpii2]

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

[jack wicks]

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

[PAR]

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.

[sharpii2]

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

[jack wicks]

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

[jack wicks]

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

[sharpii2]

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

[jack wicks]

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

[Kilisut]

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.

[BATAAN]

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.

[jack wicks]

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

[Kilisut]

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

[jack wicks]

Glenn , My main reason for liking the T. Whaler is the sail configuration,. Sailing on the Snake River, (slack water now ) becomes really boring with overlaping sail ,etc.. Plus I love the romance of a schooner, tired of looking at standard looking sailboats. Reason for the transom is I would like to put some rear window s in , maybe just for the classic look,. We also do a lot of trailering here.
Jack

[Kilisut]

So you like what Chapelle calls the "Pilot Schooner" rig of the Tancook. The foresail does overlap the main, though the jib is on a club and usually rigged to be self tending in a tack. That still gives three sheets to handle when gybing, coming up to the wind or falling off. In one of Roger Taylor's "Good Boat" books (I don't remember which one, there were four) he gives a good description of what it's like to sail a small tancook. I believe it was a review of a Van Dine fiberglass 26 footer.

Bolger doesn't like the fisherman staysail, and prefers a main staysail tacked to the deck for light air. The fisherman is quite high, which gives great heeling effect; however that sometimes gets it up into the wind on a really calm day during inland sailing.

Stern windows implies an aft cabin, it will be difficult to have even sitting headroom without a 24 footer looking like a caricature. With an aft cabin comes a center cockpit, in which case a normal centerboard becomes less of an issue. You might look at Atkin's "Florence Oakland" as an example of a V-bottom schooner in that size range.

Have you drawn any of this to scale to see what your ideas look like?

Glenn

[BATAAN]

None of these sounds like a Tancook Whaler, but a series of small schooner ideas in general. The TW was a light, large, open boat with a small cuddy, originally built very, very cheap and in a hurry, for fishing and general transport in the sometimes boisterous Atlantic. Originally completely open and 24-28 feet, the mature design was 40-50 feet. The lean ends do not lend themselves to stern cabins, etc. Change the shape and you've designed a new boat, for better or worse as will be seen on launching. TWs were fast and very handy, but change them much at all and that goes away. The original lines are very long and sharp, giving the good performance.
I suggest abandoning the "Tancook Whaler" phrase and approach the design problem for what it is, a custom vessel for a specialized use (trailering, aluminum construction etc).
Vague, nostalgic affection for a particular type or rig is not good design criteria. Like the transport of today, every work boat type of the past had a rock-solid reason to be the way it was in hull and rig, dictated by environment, trade and profit.
Sometimes these factors work for yacht use, but usually not, and a workboat-inspired yacht becomes a wholly new design.

[PAR]

I have a number of small schooners to my credit now, every single one has a transom, as the schooner rig needs bearing area aft. A few have overlapping foresails which offers power, though also has disadvantages. There are some myths about the Tancook Whaler that should be considered. First is they weren't especially fast, though with their low freeboard, heavily raked and fine ends, may have seemed so to some. These boats evolved in a unique set of conditions which forced the shape of the boat into what she became by the turn of the 20th century.

As Bataan has described they where usually flush decked forward with a small (read very small) cuddy in which a few berths were stuffed. The midship area was where the hold was divided by parting boards and of course the huge steel plate centerboard case. Then a "main thwart" which housed was partners of the main mast.

As far as it's shape, well it was likely a modified descendant of the Hampton with pinky influences as well. Eventually the hull form became it's own type as it met it's design needs, one of which was to row out to sea in slack air (low freeboard and fine ends). They were excellent sailing boats, considering what they where and the limitations imposed by conditions and service. They like to heeled over a fair bit. This tends to flatten out the well "tucked" buttocks so they can scoot with little fuss. They aren't very maneuverable and often needed sail assistance to handle a tight anchorage. This is also a boat that was much better suited to kicking the crews butts if she was loaded up with fish, rather then light. In light trim, they are squirrelly, but loaded down with fish they settle down and become well mannered sailing machines. The waterlines of a Tancook are magnificent artwork, particularly those built by the Masons.

As far as a yacht conversion, they have many things to detract from "modern accommodations". Again as pointed out by Bataan, the ends are quite fine, so stowage only in these locations. These double ended yachts have a midship area that could serve as living spaces for a crew, but the boat would need to be fairly large by Tancook standards to appear in proportion. Pound for pound, there are much better choices for a live aboard or cruising yacht then a Tancook, if accommodations are desired, which appears to be the case here.

In short, you can have the style and look of a "antique" yacht, but without all the limitations, such as draft, maneuverability, accommodation volume, etc. We call these "in the spirit of" or "in the tradition of" type yachts. I've recently done a Friendship Sloop in this fashion. Above the LWL, she looks all the part of a Friendship, but below the LWL she has divided foil shaped appendages, skeg mounted rudder and a sail drive. This makes her acceptable in modern life. She can motor with efficiency, she's far more maneuverable and closer winded then a traditional configuration and unless you've got some fins and a mask, you'll never know.

Considering your desires, you might want to look at the transom stern version of the Hampton boats, which have more bearing area aft and in large enough size could house an aft cabin. Of course this isn't even a remote possibility on a trailer sailor.

[Kilisut]

Bataan, PAR,

Yes, I know we've strayed far from Tancooks. I own Robert Post's book and have practically memorized it. I was trying to tease out what it was that Jack Wicks actually liked about the Tancook design. Wanting ultra shoal draft, aluminum construction, no centerboard case in the middle of the accomodations and a transom stern with windows seems indeed to indicate a totally different boat.

I think he was taken by the rig. The rest should be designed from the keel up. "Small aluminum shoal draft trailerable inland cruiser with transom stern and Pilot Schooner Rig" seems to be a good place to start.

Jack? Thoughts?

Glenn,
Marrowstone Island

[BATAAN]

Check out Ruell Parker's "Swansea Pilot Schooner" design. 28 ft, lapstrake plywood, raked unstayed masts, very cheap but not quite trailerable maybe. I saw two of these stern on to the quay in Key West and talked to the fellow on board. Two guys built two boats in 90 days and here they were rigging them up. Would work in aluminum but why bother? The planks were scarfed full length out of Home Depot plywood, sheathed both sides with F/G, then hung on the boat. So fast, cheap and effective it's breathtaking.

[Kilisut]

Why bother? Because Jack Wicks works for an aluminum boat company. Either he works with aluminum, or know someone who does.

Glenn,
Marrowstone Island

[BATAAN]

Understand, but AL has all its own problems with electrolysis, crevice corrosion and surface salting. A good AL boat is a very good boat, but still more expensive I think than ply and F/G. A lapstrake AL schooner would be cool. There's a builder in UK that turns out a 14' heavy dinghy in lapstrake AL and it's impressive. Lap was once used in quite large craft and is very easy to form a round hull in either in AL or wood. Gives very strong double weld. Saw a Swedish lapstrake Colin Archer being built-- bulletproof.

[Kilisut]

Yes, aluminum has it's problems. We had a Grumman canoe when I was a kid and had to rinse it carefully after any use in salt water. That was old aircraft aluminum with copper as an alloying agent.

Current alloys used for boatbuilding are far better. I've maintained steel, fiberglass and aluminum boats for Uncle Sam when I was in the Coast Guard. All my own boats have been wood. But the aluminum Coast Guard boats required less hull maintenance than anything but fiberglass.

Besides, Jack plans to use the boat on the Snake River. That's an upper tributary to the Columbia, and over a hundred miles from the sea. The salt doesn't extend upriver of the Bonneville dam. I don't think it'll be an issue for him unless he makes a _long_ trip downstream.

It's good to respect people's capabilities and resources. I'm a carpenter. If anyone suggested I build a steel or ferro cement boat I wouldn't take the advice. Jack seems to have access to aluminum construction. As much as I like glued lap (I own a glued lap Pete Culler designed Sloop - Boat) I wouldn't push it on him if he'd rather use aluminum unless I could demonstrate that it would be more affordable _for him_ in the long run.

Glenn,

Marrowstone Island.

[jack wicks]

Thanks Guys for the input,, Love it, You guys are pretty much on target. I have the book that Glenn refered to, ( Good Boats ) You are right about this boat not really becoming a T. Whaler. This boat will be probably used for wk. end camping, etc. and fun sails with our local club. The company I work for puts out around 30 aluminum boats a month and I've worked in all phases of it , currently run a16 ft C&C bender for them. I have really debated on using plywood though.
Built a 16 foot plywood sailboat 40 yrs. ago. Love the inputs, will talk more, gotta run. Jack

[PAR]

http://www.boatdesign.net/gallery/data/500/medium/BYYB-96S.jpg

This is a slightly stretched version of one of my small schooners. It may answer your needs. This is a glued lapstrake built, but there are other methods, including a multi chine that could convert to aluminum fairly easily. This is also the deep draft version, but a shoal draft version is available which draws only 27" with the board up. It can be had with a clipper bow and a longer cabin too.

[jack wicks]

Par,, Love the drawing, would like the clipper bow version and the multi chine sounds good too also the shoal draft version.. Maybe I'm getting too picky. Thanks much,, Jack

[pdwiley]

Understand, but AL has all its own problems with electrolysis, crevice corrosion and surface salting. A good AL boat is a very good boat, but still more expensive I think than ply and F/G. A lapstrake AL schooner would be cool. There's a builder in UK that turns out a 14' heavy dinghy in lapstrake AL and it's impressive. Lap was once used in quite large craft and is very easy to form a round hull in either in AL or wood. Gives very strong double weld. Saw a Swedish lapstrake Colin Archer being built-- bulletproof.

We used to have a steel lapstrake workboat on an ice strengthened freighter. Nice lines, easy to work but the amount of welding needed to build one makes me cringe...

PDW

[BATAAN]

Moitessier's boat JOSHUA and several sister ships were built with fairly wide, somewhat cupped lapped steel plates, welded inside and out at the lap. The hulls were in a jig which could spin the thing on its longitudinal axis so the welding was always downhand. Narrower "planks" wouldn't need the cup.
AL sounds like the way for our friend to go if he works in a place that cranks them out. They have the experience and materials right at hand.
4 or 5 planks a side would work as long as the deadrise wasn't too steep in the first 2.
A short boat like this needs a flattish bottom carried well into the ends to be comfortable.
Like a fat faering with a transom and a light pilot schooner (foremast right in the bows, main amidships, 1 shroud per mast per side, single headstay, 3 sails) rig. Make the rig big enough because it's easy to reduce (reefed foresail alone in a hard chance) but hard to make bigger when the wind is light.
Should scoot and leave the plastic fantastics of the same size in the dust if ballasted and sailed right.
A bigger Atkin VALGERDA with a small transom and schooner rig? Is this stupid?
I love the unpainted look of AL boats and see many Alaskan F/Vs that work hard like that.

[jack wicks]

Love the idea of a lapstrake aluminum boat, like you say with 5 or so planks per side. Would this be called an actual multi chine or lapped boat?. Dont matter anyway. I've been trying to figure out how to put a small curl on the edge of strips of aluminum just for this very reason for years. I was planning on useing 3/16 - 5052 on the bottom planks then switch to 1/8 on up the sides. Length on deck approx. 23 ft. with a 5 or 6 ft. bowsprit., 8 ft. beam. Bataan you are zeroing in on my thoughts, scary.,
Jack

[michael pierzga]

Both Oughtred's " Haiku" sharpie and Irens "Roxane" would be fast, elegant, shoal draft craft for close quarter inshore work

[pdwiley]

Moitessier's boat JOSHUA and several sister ships were built with fairly wide, somewhat cupped lapped steel plates, welded inside and out at the lap. The hulls were in a jig which could spin the thing on its longitudinal axis so the welding was always downhand. Narrower "planks" wouldn't need the cup.


I've seen NORTHERN LIGHT (a JOSHUA sister ship) up close when she was in Hobart a few years ago. As you say, sort-of lapstrake, sort-of multi-chine. A very nice looking hull form came out of it. I did think about building this way myself but settled for something simpler.

George Buehler's UNCLE SAM is a pilot schooner IIRC. Nice looking boat, single chine hull, be easy to build in alumin. I've got a set of plans for his POGO, one day I may build one just for fun.

We blasted all the paint off of one of our alumin workboats as it was more trouble than it was worth. Just had bottom paint.

PDW

[jack wicks]

I have Buehlers' book and like the looks of " Uncle Sam". I like the lap/multi chine idea also. Would like to exsperiment with putting a small radius on one edge of the planks to make for a better fit as you go up around the sides, Sound possible? May heve to try to make some type a roller set up to do this. Thanks for the input....Jack Wicks p.s. Not sure where you would start with installing the plank also, top or bottom?

[pdwiley]

I have Buehlers' book and like the looks of " Uncle Sam". I like the lap/multi chine idea also. Would like to exsperiment with putting a small radius on one edge of the planks to make for a better fit as you go up around the sides, Sound possible? May heve to try to make some type a roller set up to do this. Thanks for the input....Jack Wicks p.s. Not sure where you would start with installing the plank also, top or bottom?

Possible to put in a dish/radius, sure. Worth the bother? I don't know. I don't think I'd do it but that isn't a good reason not to try. I'm lazy.

Planking - it'd depend on the design I think and if you were going to build right way up or upside down. We had a discussion on this in the metal boatbuilding forum. More a matter or preference than anything else. I think I'd plank from the keel out because I'd build the keel first, and I'd build right way up.

For something like an UNCLE SAM I think I'd use 65x6 flat bars for the frames and 5mm plate for the hull. Mainly because I have scantlings for a slightly bigger & heavier boat and that's close to what is specified there, difference being the bigger one has 6mm plate for the hull. There'd be no point building a SAM lapstrake though as it's designed to be single chine.

PDW

[BATAAN]

Both Oughtred's " Haiku" sharpie and Irens "Roxane" would be fast, elegant, shoal draft craft for close quarter inshore work
ROXANE and her smaller sister ROMILY are two of the best designs of the last 20 years. A ROMILY is being planned in the boat yard here but in lapstrake plywood instead of its specified strip build.
Both HAIKU and the two above vessels are very dependent on light hull structure and minimal mast weight (ROMILY's mast is carbon fibre) to make them perform properly.

[BATAAN]

Lurking on a Colin Archer site I saw a guy building an aluminum lapstrake Colin Archer redningskoite upside down over conventional wooden molds. Googled "lapstrake aluminium" (note UK spelling with extra "i") and found in under images but can't find the URL now.

[jack wicks]

Thanks, I'll check it out Sounds great. Jack