Abaco Dinghy Design

[Willy Landham]

[FONT=Times New Roman][SIZE=3]This probably borders on heresy

[HALF-A-HAMIAN]

http://abacoforum.com/forums/bdingy.jpg
Might work, though will not have the same "feel". Here's a link (old) that may provide some extra insight. http://councill.home.mindspring.com/sbjournal/keys/bdingy.html

[SamFamAustin]

Good link, Half-A-Hamian, and thanks. I actually like the daggerboard but I have reservations about the spade-like rudder that aims forward. That might be a great rudder design but I've never seen it before. It seems like it could take some serious torque to windward - I would have it slightly trailing aft.

Can I ask a question - weren't many of the old smack boats framed in straight oak ribs, Carolina workboat style? I saw a picture of a Cherokee smack in Florida and it sure looked hard-chined to me, like a giant Sprits'l Skiff. Maybe I was wrong ... please more info about the project and those old smacks. :)

/sammie

[Rock Steady]

would be Bill Johnson who resides on Lubbers. I'm not sure of Bill's email address, but Junior @ SeaSpray could maybe hook you up.

Looks like a great project...good luck!

c

[HALF-A-HAMIAN]

One of the things that determined the size of the dinghy, or smack boat for that matter, was matching up a sufficient supply of proper angle limbs of horseflesh, ironwood or lignum vitae to cut the ribs from. Planking was usually Abaco pine.

[Rock Steady]

H/B

Was wild Tamarind used at all in these craft?

[HALF-A-HAMIAN]

H/B

Was wild Tamarind used at all in these craft?

Not real sure, but if anyone is in the area of Cherokee, they could ask Mr. Benny Sawyer or his son Jack, both retired from boat-building, but they built the last smack boats from Abaco for customers at Spanish Wells, the "Crystal Waters" and "Blue Waters", two very large vessels. I was there at the time they were being built, and did a little volunteer work, slapping paint and toteing materials. The craftsmanship was amazing to see them use hatchets, adze and planes to hand fit windows, doors, etc. They had a belt-drive saw mill with a 2cyl. motor, and everything else was cut by hand. I believe Carrol Sawyer was also in the business.

[peterodgers]

Willy, above he waterline, your boat looks kinda like an Abaco dinghy but i doubt if it will perform like one.

AD was a heavy displacement shoal draft sailboat. Under way, it felt like a small ship but it never sailed very well to wind.

Some say the dinghys planked with abaco pine were so heavy that they'd sink when filled with water. This was a problem because, reportedly, a lot of the boatmen in the old days didn't know how to swim.

[SamFamAustin]

I love this thread and H-A-Bahamian you sure seem to know your stuff. Anyhoo, the term "dinghy" is a little misleading because as Peterogers says these were real workboats, full displacement. They were not planing hulls or rowboats for racing, like a Whitehall. Yes, there were Bahamian "tenders" which more resemble the dinghies of today, but the classic Abaco Dinghy was a full-keel design from what I understand.

Being a historical wooden boat nut, I can compare the A/D to the Block Island double-ender, which at only 18 feet required at least two oxen to pull up the beach, being of perhaps 2 tons displacement. When you see words like horseflesh, ironwood or lignum vitae, those are even heavier, more dense woods than oak, locust, and yellow pine typically used in US coastwise boat building.

Why so heavy? It is simply that this design could handle very heavy seas. Modern boats today are built more like floating Clorox bottles and have very little stability. Maybe some of you locals can tell us that sometimes these "dinghies" were loaded with rocks as ballast so as to make them set better in the water. When fishing, the crew would throw the rocks overboard as more fish were caught. Interesting, no? This might not be exactly true for the A/D but certainly was for the Block Island double-enders. /sammie

[HALF-A-HAMIAN]

Never knew of any ballast being used. That big livewell on a smack acted as stabilization. The dinghys may have been suseptable to sinking if green, but I've been in them swamped and they floated at gunwhale level, and man could they carry a load!

[Willy Landham]

[FONT=Times New Roman][SIZE=3]There

[coconutscottage]

Wow, this looks great! I think it will be a blast to sail. It certainly won't plane, but it will go upwind significantly better than the AD.

Two things, how did you determine the location of the board? (can't tell if it is a centerboard or daggerboard, I assume centerboard) It looks like it might be too far aft and you may not have the balance you are looking for (slight weather helm). Second, not sure where you intend to sail it? I sail dinghys in Abaco a lot and you are often grazing the bottom at low tide. This rudder, canted forward at the bottom and with no skeg to hang on to, could do some serious damage (even transom) if you hit bottom when the board is up. It would not look as traditional, but you could try getting a lifting rudder from a modern 14-15 dinghy (Vanguard 15, 420, etc) hang with the traditional gudgeons and pintels and simply limit the amount that it swings down. That might be an inexpensive way of testing. Hope this makes some sense.

Best of luck, keep us posted.

Scott
www.coconutscottage.com (http://www.coconutscottage.com)

[Willy Landham]

Scott,

As far as centerboard location is concerned:

[FONT=Times New Roman][SIZE=3]There are 2 quantities that I am working to balance. These are the center of effort (CE) of the sail and the center of lateral resistance (CLR) of the hull (including the rudder and centerboard). In a small boat you want the CE to be forward of the CLR by 12 to 15 percent of the waterline length. Since the boat pivots about the CLR you would think that having the CE in front of the CLR would cause pretty severe lee helm

[coconutscottage]

Hey, sounds like you know what you are doing. I was worried about losing you with the TLAs (three letter acronyms) but you seem to be all over it.

Enjoy

[SamFamAustin]

LOL, I know what you mean. My suggestion is a centerboard with a pivot forward so it would rise if you strike any bottom. Many of the designs I've seen have the centerboard trunk just abaft the mast.

I think on a nice broad reach one could get on a moderate plane, since my recollection is that Willy is going to use extremely lightweight wood/glass construction. So instead of being nearly 1000 pounds it would only be a few hundred at most (correct me if I'm wrong).

To be on a plane only means that you're exceeding theoretical hull speed, which in this case might only be 5-7 knots. Ah, the thrill of surfing downwind with a "rooster tail" shooting off the rudder at 12 knots with the centerboard up. Life don't get much better than that!

/sammie

[Willy Landham]

I changed the rudder, added side benches, and a few other minor modifications and details.

Sam, the hull on this boat will weigh less than 200 pounds.

[SamFamAustin]

Looks beautoful, Willy!

[Rock Steady]

I second that. Beautiful!

[Willy Landham]

I'm thinking about a 4:1 mid-boom mainsheet system. Also kicking around the idea of using mast hoops. Thoughts? Opinions?

[SamFamAustin]

My opinion is that the boom sheets should be about three quarters of the way down the boom, as indicated in Chapelle's drawing and to maybe to avoid breakage, unless you want to go with fancy carbon-fiber composites for the boom itself. If not, using a traveler over the rudder and stern seems best to me, sheeting home to a cleat amidships somehow. We always used single 1:1 pull but hey, double action or more like 4:1 might be nice and avoid the blisters in a blow.

As to the aspect of the boom, remember to angle the boom maybe 10 degrees above horizontal ... we love conchs but we don't want to conch anyone's head! A loose-footed sail is perfect even with the boom raised such as this.

An interesting design for the mast fasteners is to use a regular track with clips so the sail can be wrapped on the mast the then carried home in bad weather, removable. Hoops would work as well but might be bulky. Simply release the clew and wrap the sail against the mast, tubular. Then, wrap with the head stay in a spiral manner down the mast. Unless you use heavy canvas you should be able to pull the mast, sail and all, and throw it on your shoulder to take home.

This means you need a boom that can be disconnected from the mast. THAT part might need some thinking. When stowed on the dinghy, the mast and boom would be lashed to the benches and transom but still allow for working room if you wanted to putter around, such as under oars or maybe even a Seagull motor. Think simple and how fast you can set up for a morning of flats bone fishing ... release, mount, tie, snap, blow, and go!!!

/Snap-On Sammie

[Willy Landham]

...Like this 3:1 rig?

[SamFamAustin]

Looks even better now. Hey do you care to share plans for this puppy? /sammie

[Willy Landham]

...my intentions are to put together a proper drawing package. I have a ways to go before it is ready.

[SamFamAustin]

You don't know how cool this is having 3-dimensional drawings right here on the ABACO FORUMS. Thanks Willy! :)

May I suggest to slightly extend the boats length and slightly broaden it. I would go slightly past the 14 feet usually the tops for an Abaco dinghy. Perhaps you could add more beam if the buoyancy stuff says it actually helps when pointing to windward. I am a big fan of surf boats with sails, so whatever you think.

And hey, are you going to design an optional jib with a bowsprit or what? I have no idea if the traditional dinghies ever had jibs but that does allow one to point up higher into the wind. Is this this off limits or what?

Then I thought I saw some larger Abaco sailboats from the old board, like they were built like a "sand-bagger" and had outrageously oversized sails. Let me know if you have a comment on this.

Sorry for spamming ... but you could cut down the sail area if you were mostly facing wind speeds above 15 knots, especially with a storm jib. I have sailed many a dinghy and sometimes those winds can flip you right over. Remember, you have a non-displacement hull. If you have a ton or more of displacement you can over-power the sails. Less than that, err, maybe all bets are off. /sammie

[Willy Landham]

[FONT=Times New Roman][SIZE=3]Glad you

[SamFamAustin]

I'm down with all you say WL (translation: I agree). Under 14 and no motor, you're free and clear on TX requirements. I was going to build a hard-chine Banks dory right at 14 LOA just because of that (and easy to stitch'n'glue). You're way, way ahead of me, brudda!

You mentioned an uncontrollable helm maybe due to adding a jib and I agree, but in all truth, sir, I have an "unbalanced helm" at best! The idea of having reef points is really good too. Oh, and being a former dinghy racer, I like a tiller extension and lots of room to move my weight, unbalanced as I am.

And ... if there isn't a boat make called a "Sapodilly 12" well maybe here is time for one. Like it. :D

I Yam What I Yam,
Sam

[Willy Landham]

The Sapodilly 12

[SamFamAustin]

Yowzza!

Please keep us informed as things progress, Willie. /sammie

[Sail41]

Willy,

How about some pictures of your current project? It's been quite a while since you've posted any pictures of that beautiful boat.

[MrBill]

yes please, Info on progress...


-Q: thoughts on Flotation?

[Willy Landham]

Willy,

How about some pictures of your current project? It's been quite a while since you've posted any pictures of that beautiful boat.

Hey, thanks for the interest!

Yes, I have been working quite a bit on the boat but progress has been slow. Currently I'm crafting the half frames and it is a rather tedious and fiddly process. I'll include a shot of the latest progress.

I used to have a build album on ImageStation but that site no longer exists. I've just now started to recreate the album on Shutterfly. Right now I only have the latest series of pics. It shows the sequence that I go through to build each half frame. The album location is

http://fulmar.shutterfly.com

Hopefully I'll get some time to start scanning all of my old pictures into the album.

Here's the latest shot...

[Patti Puzo]

Willy, besides being an engineer, you're most certainly an artist, craftsman, and it seems also with a bit of a historian thrown in the mix. Amazing job!

[BahamaAngie]

I can not add to Patti's posting except totally agree (and sooo neat!).

[Sail41]

thanks for the update. She's going to be beautiful. By the way,how do you keep that shop so clean???

[tim abbott]

Very nice carpentry Willy Landham! I have a question that probably has an obvious answer, in picture #12 I think it is, why do you make the individual cuts on the scroll saw & then remove the excess with a chisel? Does this give you greater control over the final curvature of the "rib"?

I agree with Sail41, my work space would not look so nice.

Tim Abbott

[Willy Landham]

Thanks Tim! Yes, I found that I got better results with the scroll saw when I made multiple cross cuts to the line and then chipped out the waste with a chisel. Plus my scroll saw makes lousy rip cuts and I don't own a band saw.

I really try to keep my shop clean. It's such a much nicer environment to work in. On the days that I don't feel like working on the boat I find it motivating to clean up the shop. That may sound weird but it's a tip that I read one time in a woodworking magazine that works for me.

[tim abbott]

Well you did a hell of a job with the scroll saw. The tools sure make a big difference, it would be nice to have the New Yankee Workshop's stuff, I wouldn't have to buy so much wood filler & caulk!

Tim Abbott

[SamFamAustin]

I agree, Tim, but Willy is a perfectionist and the lap-strake kind of wherry is perhaps the most difficult in the world to build. That's where one plank overlaps another, as you can see. It is a labor of love...

Me, I'd go with a hard-chine or compound chine boat made of marine plywood and some good oak or quality pine. Thin plywood in used over frames and then fiberglassed over, inside and out. Since plywood usually only comes in 8 foot lengths, the hardest part is joining two sheets together end-to-end. Many of the traditional dories and skiffs can be built this way - but not a rounded wherry design.

Lazy? Messy garage? Nasty fiberglass goo dripping everywhere? Guilty of all charges! Willy you rock, man.