Simple Proa

[amish rob]

Oh, I got Russell, immediately; and he’s right.

Look at the stems and ends! Honestly, it never even OCCURRED to me to be overly concerned with the aesthetics of the ama, but... why not?

I really don’t NEED another boat, but we DO need a replacement for our departed estate punt, and this is certainly a possibility. I just love it’s looks.

These are the type boats, though, that you either get right away, or never will.

ETA: that canoe from Fiji is neat. I like it!

[Etdbob]

Love the little proa Rob!

I've already posted pictures of the little two-sheet outrigger I designed over the winter, but I can't resist doing it again -
My little craft is supposed to use a clip-on leeboard as used on some of Bolgers designs.

It's undecked to be as light to carry on top of a car as possible, and maybe stash the ama, cross beams and such inside too.
I never did put any thought into the ama design at all. I figure for a paddle boat a length of 4" plastic pipe capped on both ends would serve.
For sailing it would need something much heavier. This is supposed to be a 50/50 paddle and sail design.

Doesn't an ama have to be about the same length as the main hull? After all, they both go the same speed.

I really do like the big ama of your design, I think the platform makes the boat a heck of a lot of fun.

SAM_8926.jpg

I've ah, been busy building models of two-sheets-of-plywood boats this winter, just for the fun of it!
After all, I do have four whole sheets stashed in my barn!
The big boats on top built to 1-1/2 inches to the foot i did some years ago, but all the little 1" to 1' boats I did over the winter.

SAM_9064.jpg

[amish rob]

Yep. Your danged three strips of 16” plywood lead to me revisiting this entire idea of a plywood canoe!

I still think yours looks lovely.

[Lugalong]

Having gotten fairly intimate with the proa Toroa, mentioned above, the idea of sleek hulls is appreciated, and pitting my own Oceanic Lateen against Toroa's very efficient Crab Claw certainly showed what that kind of rig was all about. Getting to the point, however, of a single chine ply canoe is a concept that I am busy with in between finishing a larger voyaging Proa, and since comment on the OP is acceptable, the following might not go by the board - dugout type Vakas with carved log amas are not exactly the most capable of burden carrying craft in the 16' range and a double canoe of equal sized hulls should do what you are asking, especially if a board or two are included for steering and leeway resistance. Doing away with leeway resisting boards/foils is of course the apparently simple way of achieving windward ability, but that sort of hull shape is NOT the quick and easy way of things.

[Etdbob]

Lugalong,

If I understand you rightly, yup, a catamaran has it all over any canoe and outrigger combo.
They are much more stable, can carry more payload and are probably faster too. I do want a catamaran some day.

The only usual advantages the canoe with outrigger has over a cat is that it is much cheaper, and that it is easier to carry on top of a small car.
I'm certain that economy is why the Figi islander shown above built the craft that he did instead of a double canoe.

For me, the portability advantage is of paramount importance, since I must carry the thing on my car some distance to any body of water.
Stashing the ama, cross beams and sail rig inside the hull, and having the whole thing light enough for two people to lift on top of a car is what I'm aiming for.

Also, the canoe can be more comfortable. With most small cats one sprawls on a platform or worse, a trampoline. Even a very narrow canoe can have reasonably comfortable seats in the hull, which can at least be used when paddling. Lastly, my wife would rather paddle than sail, which is hard to do for any length of time in most small cats. For a 50/50 sail and paddle craft, a canoe and outrigger combo seems best.

It certainly would be easy enough to build two of the hulls I designed, and rig them as a cat.
But, if was to invest that much time and material into a catamaran, I don't think I'd use flat bottomed hulls. I think at that point I'd go to V bottom hulls.

[amish rob]

To be clear, I’m “designing” a shunting canoe, or proa. One bigger hull, one smaller hull. Shunting. No foils or boards.

That much has been determined, and is set in stone.

It is also, admittedly, not at all the most efficient hull form for the purpose, nor the most efficient boat, likely. Accepted compromises, I call those.

[Etdbob]

Hey Rob, ain't you from California? So how come you ain't building a Malibu?






Seriously, I think the very best reason to build a boat, or anything else for that matter, is Because You Want To!
Efficiency ain't got nothing to do with it, and very little to do with sailing at all I reckon.

I saw a "back and forth" boat ( I'm gonna adopt that terminology from now on!) shunting upwind on the Salish 100 summer before last, first time I ever saw such a thing. It looked like a blast!

I'm very interested in your project and excited to see photos of it on the water someday. So get building already and good luck!

[Woxbox]

Doesn't an ama have to be about the same length as the main hull? After all, they both go the same speed.

On most multihulls, yes, but the Pacific proa flies the ama above the waves or has it skipping across the tops, so it's as much flying ballast as it is a hull to provide lift. Some of the traditional amas were quite stubby.

[AnalogKid]

These boats (there's a small class of them) from Rarotonga sail from the Muri Beach Sailing Club. The use the rig from the NZ I-class, or Idle Along, and clearing they tack, not shunt. However, because of that, the ama has to provide both buoyancy and ballast, so I thought Rob might be interested in the size comparison between main hull and out-rigger.
P1010981.jpg

My own proa musings from 12 years ago gave rise to this model. The card wasn't stiff enough to hold fair, and it was more an exercise in understanding the rigging based on my observations from craft in the Maritime Museum. I wanted to get some asymmetry into the hull, and was pondering whether a single panel on leeward side and a two panel, single chine design on the windward side would work, but then my head exploded trying to imagine how to make that work.

ProaModel.jpg

[amish rob]

Yar. My ama is pretty large, as it goes, but I wanted the boat to be stable when and if I sit about on the platform, and to give plenty of buoyancy forward when (if) I head downwind.

My own version is certainly an imagined hodge podge, but I am extremely fascinated by this simple type of boat and rig. I love the sheeting/shifting sailing I do in the punt, but I’d like something with a bit more room for error as I age; and if I can cast from the platform?

Bonus. Haha.

This has always been planned as a sorta/notreally boat all along; sorta good at a few things, not really good at any one thing.

As for tacking? Oh I have a few wild ideas for more tacking canoes, and I’m chipping away at helping the youngest build a tacking canoe.

[amish rob]

I love pictures of ALL multihulls. They ALL teach SOME lesson.

Plus, I think they’re cool looking! That yellow tracker looks lovely.

[Russell Brown]

"Toroa" would sail down to a reach with no steering except occasional weight shift. It's a pretty awesome feeling riding on the platform, pretty comfortably flying through the chop without doing a thing except watching. That boat has the world's best ama hull shape (I think). Ama hull shape is pretty important and all the ones I did paled in comparison.

[P.I. Stazzer-Newt]

Have you looked at the KIR 7 plans?

They can be found by searching, or if you pm me an email I can send you a copy.

[Lugalong]

in achievingte above

Lugalong,

If I understand you rightly, yup, a catamaran has it all over any canoe and outrigger combo.
They are much more stable, can carry more payload and are probably faster too. I do want a catamaran some day.

The only usual advantages the canoe with outrigger has over a cat is that it is much cheaper, and that it is easier to carry on top of a small car.
I'm certain that economy is why the Figi islander shown above built the craft that he did instead of a double canoe.

For me, the portability advantage is of paramount importance, since I must carry the thing on my car some distance to any body of water.
Stashing the ama, cross beams and sail rig inside the hull, and having the whole thing light enough for two people to lift on top of a car is what I'm aiming for.

Also, the canoe can be more comfortable. With most small cats one sprawls on a platform or worse, a trampoline. Even a very narrow canoe can have reasonably comfortable seats in the hull, which can at least be used when paddling. Lastly, my wife would rather paddle than sail, which is hard to do for any length of time in most small cats. For a 50/50 sail and paddle craft, a canoe and outrigger combo seems best.

It certainly would be easy enough to build two of the hulls I designed, and rig them as a cat.
But, if was to invest that much time and material into a catamaran, I don't think I'd use flat bottomed hulls. I think at that point I'd go to V bottom hulls.

Probably need to do some explaining here , Rob, because I am not suggesting a catamaran. Shunting rather than tacking is definitely what I am into and am suggesting.
Then I do see your point about paddling on the off-side as well as on the ama side between the cross beam/kiato. Problem that I found with a 16 ft'er, was that at least 6ft space was needed between beams in order to accomodate 2 paddlers.
Since I wanted an efficient paddler, while also a lively sailer, more length was the required to achieve this. Then when I tried sailing in company with Toroa, my small/ low volume ama ( which could easily fly or be sunk for roll-under righting) was shown to be inferior to one that could at least float 2 persons and had reserve buoyancy enough to allow hiking out to w/ward, without behaving like a submarine in the lulls.
Accepting the fact that smaller hulls are convenient for car topping or carrying on a pushbike trailer, the buoyancy characteristics of a dory-like hull form offer a displacement advantage by dint of their shape, or decidedly so compared to a V hull of less than 90deg.
Whether you prefer a tramp over a slatted deck or not, the advantage of a shunter rig swinging out to lee rather than sweeping the deck, is a feature that makes a proa more favourable over a ca,t IMO anyway.

[amish rob]

Have you looked at the KIR 7 plans?

They can be found by searching, or if you pm me an email I can send you a copy.

Oh, she’s sweet! The hull panels were actually a key revelation for me. On my own goofy boat, I cut the side panels in a similar fashion, but I went with the flat bottom because I wanted to keep hull depth as minimal as possible, to make the compromise even weirder.

[amish rob]

in achievingte above

Probably need to do some explaining here , Rob, because I am not suggesting a catamaran. Shunting rather than tacking is definitely what I am into and am suggesting.
Then I do see your point about paddling on the off-side as well as on the ama side between the cross beam/kiato. Problem that I found with a 16 ft'er, was that at least 6ft space was needed between beams in order to accomodate 2 paddlers.
Since I wanted an efficient paddler, while also a lively sailer, more length was the required to achieve this. Then when I tried sailing in company with Toroa, my small/ low volume ama ( which could easily fly or be sunk for roll-under righting) was shown to be inferior to one that could at least float 2 persons and had reserve buoyancy enough to allow hiking out to w/ward, without behaving like a submarine in the lulls.
Accepting the fact that smaller hulls are convenient for car topping or carrying on a pushbike trailer, the buoyancy characteristics of a dory-like hull form offer a displacement advantage by dint of their shape, or decidedly so compared to a V hull of less than 90deg.
Whether you prefer a tramp over a slatted deck or not, the advantage of a shunter rig swinging out to lee rather than sweeping the deck, is a feature that makes a proa more favourable over a ca,t IMO anyway.

Sweet! I just wanted to be clear that I’m stuck in this rut, for now. Haha.

I think the best part of reading other peoples opinions is that it either confirms my own guesses, or it makes me think in a way I haven’t.

[amish rob]

And, thank you all. I mean, I know I’m not the only one who likes to talk about boats, eh?

[amish rob]

BF9B15B8-3C3D-454F-AEAD-D4FB7265F264.jpg
Just to show the rudimentary rig some more. I DO plan to step the mast to the windward side of the hull. Not on a washer. I do plan to use and adjustable shroud, though, with a “whoopie sling” eye splice; a Brummell eye with a long tail and stopper or back splice. I use them for my hammocks.

I saw some of the simpler canoes and I want to emulate those rigs; a mast, a sail, a sheet, maybe some brailing lines, and a shroud. Having a bundle of stuff that essentially stays together makes life easier.

I fully realize it will collapse of backwinded, and be a bit of a bear to shunt without a tackline and etc, etc. I’m no ace of a sailor, anyway, and most of that is across bays on alpine lakes; about 95% reaching. I’m not trying to do anything except capture the pure joy of moving in a boat without doing a thing except steering and sheeting. And, this ain’t intended to do any great crossings or wild sailing adventures. If I ever lost sight of land, I’d likely drop brown trout through the platform slats.

I did make many concessions to other uses, too, and that’s a primary reason for the big ama. I wanted bouyancy for when sailing and paddling (or sculling...) but also for when we’re just hanging out stomping around on the patio, or basking like lizards after a brisk swim.

A camping adventure or two aren’t outside the realm of possibility, either, and dang if a proa has a convenient place to set a wee tent up. If it has a buoyant ama...

I did go to some pains to keep the hull shapes as similar as possible, too, based on videos and interviews and etc. etc. Compromises abound, as they often do with boats, but I think I came up with a pair of hulls that are close cousins, and I hope they behave that way.

I tried to keep the flare close.

E0C3ECAF-0EBA-4006-B532-68ED76FA8193.jpg

42F84E4E-68DD-4745-9471-ED4186BB13A1.jpg

And, I like this picture of the ama. I don’t know why.
5F6A69F4-EB24-4292-8273-FB11C1973841.jpg

Pictures are hard, and especially with two hulls separated. I have spent the past few days staring. A lot. I move her, and shift her, and shunt her. The tape is one of the props I’ve been using to simulate heel, to help see the hull from different angles, to imagine what the hulls would do.

Why are boats so fun?

[WI-Tom]

You'll have to be sure to pack "Call it Courage" aboard--looks like the right boat for it.

CIC.jpg

Tom

[amish rob]

Unlike many, I don’t take music or books on board. I can read and listen to music in more comfort at home.

What I cannot do at home is hear and see the things that live where boats float.

Just a personal quirk. I never use music when running or cycling or doing any exercise, either.

I may, however, pack along this bad boy to boil up some tea or coffee...
1AEF4405-FFB7-4B4F-8BF8-62B2911CBDE2.jpg

[amish rob]

FE26AF95-5BF1-4276-9B91-23E87ABA6A96.jpg
The original “wild idea” cartoon. A sort of “I wonder...” moment. Really, the end result isn’t too darned far from the original cartoon...

3742ACA2-C9D1-4ECE-819C-9BE809DB0AAE.jpg
Hull panel layout shows how much was simply stolen and rehashed. Nothing novel except the combination of shapes, I think; and I don’t even think they are novel.
I’m sure I dumbed onto a combination that’s been before, and will again.

ETA: it may not be obvious, but the side panels are NOT identical. Not! One is longer, and one gets a slight trim, to account for the difference in shapes necessary because of the asymmetrical bottom and identical flare either side. Nothing major. Just normal boat-building stuff.

[Dusty Yevsky]

I'm very curious about how a flat bottomed proa that won't use foils will handle weather helm. Traditional proas have a fair amount due to the ama drag and, as I'm sure you know, the ancient engineers developed sharp, assymetric foil shaped hulls to counter this tendency. Are you taking any specific design steps to deal with this? Do you think asymmetry of the hull will be enough?

[amish rob]

What kind of graphic motif would be most appropriate for a boat like this? I really like the boats with bands of symbols, like waves and etc.

I am not out to emulate, nor offend anyone’s culture, but I don’t like plain paintjobs, and I love to embellish things. I do like the red hull, and thought maybe a white bottom (and decks) just for contrast, with a stripe of black graphics below the rubrails?

I am very thankful for any suggestions, or for anyone telling me to don’t do that, if it’s a Nono.

[amish rob]

I'm very curious about how a flat bottomed proa that won't use foils will handle weather helm. Traditional proas have a fair amount due to the ama drag and, as I'm sure you know, the ancient engineers developed sharp, assymetric foil shaped hulls to counter this tendency. Are you taking any specific design steps to deal with this? Do you think asymmetry of the hull will be enough?

Weather helm? Maybe progress to windward?

As stated, I don’t much care, provided I can make a decent close reach, it will be enough for any sailing I might do. For all the other possible roles the shallower draft is much more essential than a few degrees.

Also, I have based this boat very loosely on two other simple proas that work quite well for their owners, but I have added some of my own ideas to manage the drawbacks they experienced. Standing on shoulders, as it were.

No doubt a deeper, sharper hull would be more resistant to leeway. Part of the reason for the big ama with a flattish deck is to allow the option to add a dagger, should leeway become a serious issue.

Definitely something I gave a lot of thought to, and am wondering a bit about, still, actually. We shall see, hopefully. Until then, it remains academic, and it picks at my brain.

The best answer I can give to any of these is: Uhhhh, I hope so.

As to whether it will have weather or lee helm? Well, that’s also guesses, but that will all hopefully be carefully balanced to help drive the thing where I want. Shifting weight and changing shape and a steering oar and mast tilt and all that stuff will be how I deal with weather or lee helm at any time. He said, as if he knew WTH he were saying...

I like the questions a lot, as they raise issues I may not have thought about, and often in new ways. We all see and think differently, eh, and have different experiences.

[Paul Pless]

What kind of graphic motif would be most appropriate for a boat like this?

dancing bears

If my words did glow with the gold of sunshine
And my tunes were played on the harp unstrung
Would you hear my voice come through the music?
Would you hold it near as it were your own?

[rael dobkins]

Rob, I like it! Sweet and Simple... Welcome to the Shunting world bro.
Good Luck with the build.
Keep Shunting, Balkan Shipyards.

[amish rob]

Thanks, Rael.

And thanks for all the advice!

[P.I. Stazzer-Newt]

Rudder, rudders, steering oar, steering paddle, or just weight shift???

[Lugalong]

I'm very curious about how a flat bottomed proa that won't use foils will handle weather helm. Traditional proas have a fair amount due to the ama drag and, as I'm sure you know, the ancient engineers developed sharp, assymetric foil shaped hulls to counter this tendency. Are you taking any specific design steps to deal with this? Do you think asymmetry of the hull will be enough?

Rael Dobkins has just showed up and is to my knowledge one of those who have experience with a flat bottom
and a flattish run of the lee chine. Then, he makes use of a daggerboard in the ama, if I remember correctly. Perhaps he will illuminate the possible advantages/disadvantages of this configuration.

Interesting thing for me in the discussion so far is that Toroa has the best shape ama (according to Russel), and this appears to be as close as dammit to a 90deg V.

Since an ama is nothing more than the windward hull on a Pacific proa, the question is begging as to why this is not the best bottom type for a proa, period!
Flat is OK if you want max hull volume with minimal draught, but then don't mind greater draught by using boards/foils having extra depth over the hull anyway.
There are canoes with sharp bottoms that still use boards through slots and cases (such as Toroa does) and there's no arguing about foil shaped boards being more efficient WRT wetted area reduction and leeway control.
Ever since plywood canoe hulls have been made, the 90deg V has been taken as a good compromise where section shape for wetted area and ease of build has been the concern.
I am building hulls with flat bottoms primarily for reason of build convenience and maximising hull volume while aiming for compact packaging when trailering or transporting on deck ( where windage reduction is desired).
Where building facilities allow a complete hull to be assembled, there is every reason to simply go with a 90deg V shaped hull.

[amish rob]

34E54A2A-78B9-4B0A-8BE9-F8CF1A5C8E18.jpg
I hope to be able to steer with no rudder nor oar. I hope...

7D7884A3-7E2C-47C4-85B4-A989F78BAF99.jpg
I am going to build one of these wild sculls, though, either way. On the big’un, I’ll glue and lash some block to the crossbeam to support the oar lock, and probably under the end of the platform board.

And, of not, well I DID on this one.

[Clarkey]

Is that an 'AD scull' or a yuloh?

[amish rob]

Yes. It is very much a sculling oar based on the AD scull, but just a miniature stand in, mostly to how it would fit in and where.
The geometry is not ideal, for sure, bit it’s good enough to reassure me a full sized on would work. I did taper the wee blade a bit, though.

That the AD style scull also reportedly works as a rudder is a bonus!

[Clarkey]

Is it the right way up on the photo showing it mounted to the boat though?

I do love the idea of an AD scull seamlessly transitioning from propulsion to rudder, I imagine it must feel great as the sail power comes in. I think there is a lot of mileage (literally!) in human powered 'motorsailing'. I want the same 'bionic' sensation you get when pedalling an electric bike.

[amish rob]

The pretend scull for the boat is just two sticks left over glued together. They had roughly the right shape and size.

My takeaway for the AD scull is it needs to be carefully measured to fit each specific application, so I’m not even TRYING to emulate one at scale.

I made something I could wiggle forth and back to check clearances, and maybe put into the hands of an action figure, if Quad lets me borrow more guys.

But, yes, I think it does look backward from the backward looks of the typical AD.

[rael dobkins]

The AD-Scull invented by Mr Atsushi Doi is a marvel for coming into shallow bays with a shunter, it can drive and steer yet has no problem running aground, it just rises with no issues. I built a bunch, and the recipe I found to work best is divide it into 3 sections, 1 third blade, 1 third shaft and the last is the handle which is the top third. This way the ratio is a 1:2, since the distance from the handle at the top to the fulcrum is 1 third, vs the other 2 thirds below the fulcrum.

It's easy to use with little effort and is great to get her going fast after a shunt. I bend the handle upwards about 15 degrees, I will always have one on my boats and Mr Doi deserves some serious credit for inventing this tool, nothing beats it for single handed propulsion on a proa.

Lugalong, As for flat bottoms, I love them. For a SMALL Cruising Proa, load capacity is a much bigger problem, than loosing a little speed due to the extra turbulence, caused by the hard chine.... So flat bottoms rock!

Keep Shunting,
Balkan Shipyards.