Herbie the Volkscruiser Proa
It’s a real juggling act at this size, that’s for sure. I could make the bunks a lot wider if I lower the side pod overhangs and/or raise the roof, but then the boat gets seriously ugly, not to mention more windage, weight, etc. So I just decided to keep things reasonable for the 34’, and if full standing headroom and queen-size bunks are required, there is always the 40 footer! 😉
All this is merely approximate, and a full-size cardboard/plywood mock-up would be a huge help in optimizing the space.
Bill, I like your reasoning. 24’ is about as big as I’d want to go for a trailerable boat. Even though Herbie is longer than that, he’s only 7.5’ wide, and so demounting and trailering is possible for long winter storage, and he’ll also fit in a container.
Distance between major bulkheads is 8’, so the masts are 24’ distant. I can’t really get the masts much off center because the hull bottom is quite narrow there, and I want as much bury as possible. Besides, I’m strongly considering the ability to sail Herbie as an Atlantic proa if I ever really want to scare the sh*t out of myself.
I really, really like this concept. Those overhangs just shout ‘Bookshelves!’ to me, even though it’d be heavy. Unfortunate. But, think of all the other things you can put in there, if you can keep it light.
Thanks, I think, Editor 😉
Herbie, and Nixie, have rekindled the idea that a smallish relatively inexpensive coastal cruiser to winter along the Yucatan is doable.
In doodling a five sheet solution the issue of rudders still exist. Here’s my current thinking. Relatively easy to build, there should be a lot of meat in the upper part of rudder to bury the blade. Most of the time you wouldn’t need to use the thing but would be handy approaching a mooring or running an inlet.
Cheers,
Skip
Rudder redux…
Even simpler, using a variation of “Too-cool Solution” attach the rudders to forward bulkhead with figure eight style hinging out of webbing. The hinge line then alternates from one face of the juncture to the other and stays flat at zero input. A little elastic strapping at zero might be helpful. If the forward rudder goes completely whammo it would be slammed a full 180 degrees, not the end of the world if the blade/forward bulkhead are reasonably narrow.
Little more thought to incorporating a drop blade in the deal that would work in shoal water, think the whole thing might end up being solid timber and tough.
Skip
You know, come to think of it, you could make a rudder trunk, that had a “jacob’s ladder” hinge and link the two trunks with a flex rod. Now you have two height adjustable rudders!
I think you still need a linear bearing for the rod, since it needs to get longer as it bends.
But interesting!
Rudder redux…
Even simpler, using a variation of “Too-cool Solution” attach the rudders to forward bulkhead with figure eight style hinging out of webbing. The hinge line then alternates from one face of the juncture to the other and stays flat at zero input. A little elastic strapping at zero might be helpful. If the forward rudder goes completely whammo it would be slammed a full 180 degrees, not the end of the world if the blade/forward bulkhead are reasonably narrow.Skip
Wearing my stupid hat today. I think I need a sketch—at least a cross-section? Thanks.
Dave
Wearing my stupid hat today. I think I need a sketch—at least a cross-section? Thanks.
Dave
Not alone there, Dave - I’m confused too….
You know, come to think of it, you could make a rudder trunk, that had a “jacob’s ladder” hinge and link the two trunks with a flex rod. Now you have two height adjustable rudders!
Yes, that’s what I would be inclined to do, dagger rudder boxes rather than the ‘staples’ method. The rope or tape hinges fit with the, simple/minimal philosophy.
Mal.
For those, like me, who needed a picture. The trunk is cut away and the down-haul/up-haul arrangements aren’t shown. The steering bridle would probably sit on top of the trunk and slide (or be hauled) fore-and-aft as the boat shunted. For those who worry, the ‘fixed’ part of the rolling hinge could have its own pivot to allow it to avoid damage in the event of grounding. The steering rod and bridles would ensure that the other rudder lifted too.
Rudder redux…
Even simpler, using a variation of “Too-cool Solution” attach the rudders to forward bulkhead with figure eight style hinging out of webbing. The hinge line then alternates from one face of the juncture to the other and stays flat at zero input. A little elastic strapping at zero might be helpful. If the forward rudder goes completely whammo it would be slammed a full 180 degrees, not the end of the world if the blade/forward bulkhead are reasonably narrow.Skip
Wearing my stupid hat today. I think I need a sketch—at least a cross-section? Thanks.
Dave
Here’s a sketch, Herbie+ size (4’ tall) most of the bits from 1-3/4” LVL beams. The break-a-way feature was pr1066’s idea some time ago on another thread. I really need to cogitate on a Nomad size solution first, but the idea does have some merit I think.
The picture is a trial of the hinge full sized for the flap hinge on Bionic Broomsticks’ wingsail under construction. Hinge is two pieces of tape put together face to face the width of hinge area. Pieces are applied alternately, seem to work surprisingly well. FWIW the 10” chord 59” span tailplane currently weighs 7 oz. still needs basalt tow spar caps and rest of packing tape skin.
Here’s a sketch, Herbie+ size (4’ tall) most of the bits from 1-3/4” LVL beams. The break-a-way feature was pr1066’s idea some time ago on another thread. I really need to cogitate on a Nomad size solution first, but the idea does have some merit I think.
The picture is a trial of the hinge full sized for the flap hinge on Bionic Broomsticks’ wingsail under construction. Hinge is two pieces of tape put together face to face the width of hinge area. Pieces are applied alternately, seem to work surprisingly well. FWIW the 10” chord 59” span tailplane currently weighs 7 oz. still needs basalt tow spar caps and rest of packing tape skin.
A slice of genius here, Skip. This is *exactly* what I was looking for with the “too-cool solution” thread, and you’ve provided not one but *two* applications.
Never would have occurred to me to use the Wharram hinge for attaching a flap to an airfoil. I love that! Light, strong and dead simple. For aerodynamic reasons, you want an opening between flap and main element, to re-energize the lee side flow, but that’s of lesser importance than just getting the articulation in order to allow the wing to go asymmetric. If one were concerned about the life of simple tape, it improves most any tape’s adhesion if one first masks then sprays a coat of contact cement (like 3M Super 77) onto the “parent” material only, then stick the tape to the sticky cement. It makes tape jobs last forever.
This solution would, I strongly believe, be rule legal on a Moth, and might be the way forward to bringing wingsails into that class. Anybody here know a moth insider?
You know, come to think of it, you could make a rudder trunk, that had a “jacob’s ladder” hinge and link the two trunks with a flex rod. Now you have two height adjustable rudders!
Yes, that’s what I would be inclined to do, dagger rudder boxes rather than the ‘staples’ method. The rope or tape hinges fit with the, simple/minimal philosophy.
Mal.
Very cool Chris, Mal. This presupposes that the the bottom of the trunk is above the waterline and the whole thing is a fitment outside the boat right? If immersed it’s going to be pretty draggy, though putting a fixed trunk through Herbie’s overhang would be an elegant way to achieve this as well.
The Jacob’s Ladder hinging is an outstanding application of the principal, but I think we’re now adding “friction” to the system. Friction’s not the right term, but my words just aren’t there this morning. (“Use your words, Dave”)
In order to hinge the trunk from its fore or aft inboard corner, we need to move the average center of the whole thing away from the hull—and this is a loaded board, pushing hard in the other direction. On the one hand, it’s going to have a strong “self-centering” feature, analogous to adding caster to a car wheel (Hey, maybe we don’t need no stinkin’ shunting boards!) but at the same time, it’s going to require some significant force to turn these rudders. Too much? Dunno.
I love that this whole thing becomes a bolt-on system for trialing or testing. You can bolt—even C-clamp—it to an existing boat, see how well it works. If it’s a complete cock-up and we’re all wrong, there’s a smaller, cheaper pile of scrap to get rid of. 😉
Regarding raising and lowering of rudderboards; systems already exist for doing this remotely and/or with pretty big boards, via lines and blocks for raising and lowering boards in their trunks. For simplicity’s sake in a small boat, there’s nothing quite like just reaching out and grabbing the top of the board—if you can reach it. As these are counter-rotaing boards, it is likely not necessary to get them way out to the ends of the boat; counter-rotators have been found to work very well when mounted just fore and aft of the crossbeams/trampoline. ie, ~8’ apart on a 16’ proa.
Dave
Hi Skip,
Really like the double hinge. I guess it’ll need something to apply a force to keep them closed up and stop them doing this…
The Jacob’s Ladder hinging is an outstanding application of the principal, but I think we’re now adding “friction” to the system. Friction’s not the right term, but my words just aren’t there this morning. (“Use your words, Dave”)
Dave
The really great thing about this device is that it doesn’t suffer from rubbing friction - you’re wrapping a thin flexible tape onto one surface as you’re peeling it off the other. There is a bit of resistance from the forces needed to bend the tape but no rubbing (wear, debris) at all. Of course, if you use rope then there will be inter-strand rubbing. If you use tape then you have to provide someway of keeping both tapes loaded in tension since you can’t push something with a piece of string.