Mike Crawford mcrawf@nuomo.com>:
>Gardner,
>
> Good points.
>
>SPEED.
>
> I didn't meant to imply that you want bugs in your teeth in really
>shallow water. You just got lumped in with the low-draft requirement
>because that's high on your list.
>
> Light wind performance is actually more important that max speed to me
>as well. While I do need to hit 20 knots before I stop counting (I've
>been to 17.5 so far, so maybe this summer...), I'm starting to prefer 8
>knots to 12 or 15. At some point in the double digits, the apparent
>wind turns into a roar and things in the water start approaching too
>quickly, and things aren't as relaxing as they were at 10 or below. I
>want the *option* to fly across the water, but the ability to move
>nicely at low wind is more of a draw.
>
> Which is why I want the proa with an unstayed mast: you can have an
>otherwise dangerous amount of sail area up (for a singlehander), and go
>from full-on to full-off isntantly, as needed. Because gusts and
>squalls do happen.
>
>TILLER.
>
> The tiller would work like it does on Rob's woodenboat challenger and
>10m camper in the Files section of the group -- a long trimaran-type
>extension on a standard tiller at the top of the rudder.
>
> The extension can be modified in length by a few feet with a twist,
>providing some flexibility in the cockpit. Some of these extensions
>have a ball-shaped end that will drop into a keyhole-shaped receiver in
>the cockpit, so you can pick a length (neutral steering) and then lock
>it. See the Forespar tiller extension lockbox:
>
> http://www.forespar.com/products/tiller-extension-lock-box.shtml
>
> I'm sure you could rig up a similar system for an extension with a
>hand grip as well.
>
> So if you shunt, just drop the aft tiller into the lock, switch sides,
>and grab the new aft tiller.
>
>AUTOPILOT.
>
> As for an autopilot, I'd use a Raymarine ST-4000 tiller pilot. The
>control goes inside, or at least at the cockpit, and just the mechanical
>portion sits out, the base connected to the leeward hull, the end
>connected to the tiller (not the extension). I use one of these on my
>catamaran with great success. If patched into the nmea system, you can
>even have it steer to GPS waypoints, or to the average wind direction of
>the last minute.
>
> Plus, I just love using the Raymarine wireless smartcontroller remote,
>hanging out on the bow tramps and steering with a button. It's not
>necessarily a wise way to sail, but when motoring back to the mooring
>against the tide, it's great fun.
>
>12' FOLDED BEAM.
>
> I hear you about not being able to fit in a full-sized permanent
>cockpit in to a 12' width while folded. I've tried, and if everything
>is just so, it might be possible, but only if I skimp on the interior,
>the cockpit, or both. Given that I'm shooting for a table inside, and a
>6' cockpit, there may be no way it can happen unless there's a funky
>system like your Contrarry where the cockpit overhangs the leeward hull
>when folded.
>
> Going along with your idea of a removable cockpit (or Dennis'
>flip/folding one), how about a 14' width to 16' width while folded,
>going down to a 10' or even 8' width while trailering?
>
> I think a 14' to 15' berth width is pretty standard for a 48'
>sailboat, so the boat should still fit into a marina with the cockpit
>intact, without messing with the cockpit, and still allow a narrower
>trailering width than my 12' goal. That would be a neat combination.
>While I wouldn't mind disassembling the cockpit for the rare trailering
>session, I wouldn't want to have to mess with it every time I leave or
>tie up to a berth.
>
> This would be the best of both worlds.
>
>FOILS.
>
> Could you point me to an image of Todd's design with a fixed vertical
>steering board? I think you mean the one here:
>http://www.youtube.com/watch?v=Jn8fr0PaUqg , but want to check
>
> If you went with this, how would you incorporate raising and lowering
>the foils? Or would you just count on your hull design to counter
>leeway, and have the foils raked way back for sailing in skinny water?
>And how would that work with the hull profile you're planning on?
>
> I can see Todd's hulls being *great* at preventing leeway, but I'm not
>so sure how well they'd work on a 40+ footer at a very low draft. But
>then I haven't tested them, nor tried to calculate the draft at full
>displacement. If it works, there's a lot to be said about effective
>leeway prevention that doesn't depend upon any foils.
>
> - Mike
>
>
>
>Gardner Pomper wrote:
>>
>> Mike,
>>
>> Just a couple of comments:
>>
>>
>> BD has special draft requirements, as does Gardiner's plan to
>> sail in the Chesepeake, and both could be nonoptimal with
>> low-draft beam-mounted rudders. Without enough foil in the water,
>> it's easy to go from laminar to non-laminar flow, and then the
>> foils become a lot less effective. But such is the challenge with
>> a 48' boat designed to sail in 3' water, and yet somehow be
>> expected to hit 20 knots (by observers, not by the owner).
>>
>> I don't want to sail at max speed (15 knots will do for me!) in 3' of
>> water! I just want to be able to sail at 5-6 kts in shallow water. I
>> want to sail at 15+ kts in deep water (> 30'). I even want to ghost
>> along at a couple knots in 1-2' of water (with a soft bottom, like
>> mud or sand) for anchoring. It is very important to me that the
>> rudders raise, but it is also important that they lower to 5' or so.
>>
>> Just as important, rudders on the beam would permit simple
>> tiller extensions all the way to the cockpit, which is something
>> I'd definitely like to try. It's a simple system that wouldn't
>> care one way or the other if the boat were folded or unfolded,
>> won't stretch out of shape, and will be more fun than using a
>> wheel. At least for me -- I much prefer tillers.
>>
>> I am not clear on the tiller idea. I would be happy enough with a
>> single tiller, but I am having a hard time seeing the use to two
>> tillers; sometimes one at a time (having to stow the other partway
>> through the shunt) and sometimes both (to be able to use both
>> rudders). Am I just missing some simple way to do this? Plus, I am not
>> willing to give up on autopilots when cursing, so how will that work?
>>
>> Because of these questions, I am trying to move forward with the idea
>> of using a wheel. As much as I love how clean Rob's new rudder desgn
>> is, I don't see how to make the steering simple. Instead, I think that
>> Todd got it right with his rudder design, where the steering board is
>> fixed vertically, and the rudder case is pinned to that board and
>> kicks up independently. That allows the steering system to work
>> regardless of the cant of the rudder, or to impact.
>>
>> Btw, I have also hired Rob to try to help put a design to paper with
>> all my weird-ass requirements (on water folding, fit in a shipping
>> container, etc). I think I may have had to give up on the 12' beam for
>> trailerability (sorry, I tried to put that one in just for you!) but
>> for now, there would be (minor) disassembly to make that happen (have
>> to remove the removable cockpit). When Rob has beaten some sense into
>> me and come up with drawings, I would also be happy to share with the
>> group (with Rob's permission).
>>
>> - Mike
>>
>>
>>
>>
>