Subject: Re:Rare bird and schooners
From: Mike Crawford
Date: 2/1/2006, 6:08 PM
To: rob dalton


  I believe Rare bird did 11.5 knots in 15 knots of wind.  But with that bendy rig, a fouled bottom, and a huge load, that's still quite a feat.  I look forward to hearing about what Blind date does when it gets tuned.

  I definitely agree with you on the schooner rig.  I also agree on not screwing around with too many sails.  Headsails would require way too much effort and cost, from building the boat to handle the loads, to purchasing additional sails and rigging, to buying, installing, and grinding winches, to the big hassle of furling one end and unfurling the other on each shunt.  No thank you.  If I wanted that much work, I wouldn't be looking at a harryproa.

  As you and Rob have pointed out, mast height is key in really low wind.  I'd much rather have two 18m masts, reefed much of the time, than a single easyrig (or shorter masts) with headsails.  This would require a sail that's easy to reef, but that's not a very difficult thing to find.  If you've got a good way to control sail shape, such as with a wishbone una or an easily-adjustable outhaul and vang on a standard main, you can also reduce power very significantly just by flattening the sail and letting out the mainsheet a bit.  No shrouds to get in the way!

  Another benefit with the schooner is that any sail you carry is a spare!  You could carry one or two spares, plus two short 10m masts with heavy dacron sails as emergency rigs (in case a mast buckles).  Everything becomes easier when there is only one kind of sail.  There's also more mast buoyancy, which I like a lot.  I don't intend to go over, but if it happens, I like the idea of having an option of self recovery.

  A 15m lw hull Harry with a tall schooner rig would be a sight to behold.  I imagine it could easily surpass wind speed, and also go past that "emotional" 20-knot mark.

  Besides, you can always set up an outleader if you've got a really long downwind run.

       - Mike



rob dalton wrote:
I had thought of the lw hull wtih rig tucking under. It should fit without widening the beam if using a schooner rig as you need less bury and the bury would come where there is a little less beam on the corredponding point on the ww hull. Putting the lw hull over can actually be a plus if you have enough room as it makes it dead easy to remove and replace the masts as the holes and masts are than horizontal. The combination could then be winched up to the sailing position.Much easier than rigging up a gantry to place them in the holes vertically. The process I imagine for getting the boat to the water if there is a wide enough ramp to take the expanded boat. Lee hull is tucked under ww hull on its side. and cross beams are separate. possibly lashed to the roof of the ww hull and supported with trailer framework. The crossbeams are tipped into the lw hull holes form the top of the roof. It may need some giuding boards and rope restraints to do it on your own but it should be possible to sort out relatively easily. Once the beams are in the lw hull sockets thay can be attached to the folding system iwth a couple of rods. The masts are taken out and possibly using something like a piano trolley guided horizontally into the mast sockets. The beams are then winched into placeand locked down.  The bottom of the lw hull would have to be supported by the trolley as it went out. Here comes the difficult part, the instability of having the boat so of centre. The possibilties are  sliding the whole boat sideways on the trailer to center the weight and supporting the boat under the wing deck and the crossbeams or rotating the trolley 90degrees and letting the trolley support the lw hull. 
The other choice is to put the boat in the water before the masts are  in and put the masts in from the beach or even from the water .
Without the folding system the main difference is that you have to manoevre the lw hull around with the masts and crossbeams in place and tip the ww hull to allow the sockets and the crossbeams to line up, and you would have to have a wide enough ramp.  On your own with uneven ground it would be dificult. with one other person to help with fine adjustment it shouldn't be too hardThe Farrier systems are very robust as they have to support a strong torque on the joints. The Harry, though having longer beams, only has to hold up the ww hull without a great deal of torque so the folding machanism really only has to support the loads of assembly.. There would be some extra weight in the flanges to hold the beams in position rather than having the sockets.
Don't know how muach extra the weight is for the horizontal  folding system but apart from the bolts you have two extra surfaces and a centreline with less resistance to sheer.
According to Robs posts, didn't Rare Bird do 18knots in 20knots of wind with a fouled bottom? Don't know how much faster a harry will be with a couple of tall Una rigs. I would avoid the hassle of screechers as it means you have to start putting in extra weight to take the loads. With the schooner rig the rigging loads are concentrated in one plane and the rudders aren't far off. There are a lot of loads trying to get decent luff tension on a foresail. It would be a pain to shunt.
regards,
robert

Mike Crawford <jmichael@gwi.net> wrote:

  I did muck up the conversion.  I meant 60'/18m masts with a 50'/15m lw hull.  I have no idea how I could have come up with 23m -- none of the factors could yield that number, even if I reversed them.

  I'm starting to like an expanded Harry design.  The drop in weight would help light wind performance, and the smaller design would mean a lower cost.  That would be one fast boat. 

  One of my problems is that I've gotten addicted to the speed of the current cat, which has hit 17 knots, and hopefully will reach 20 this sailing season (new sails, more experience).  More than the top end, though, is the ability to sail in wind that keeps others at the dock.  I don't necessarily have to fly about like a madman, but it's really nice to move at a good clip in winds that would just leave my bobbing about in my old boat.  I have a feeling that a schooner rigged 15m Harry would even be an upgrade from my stiletto.  Especially when the wind is strong enough to reach, but not quite good enough to tack.  Shunting would be welcome on days like that.

  I can't see using the Farrier system because it tilts the ama down when retracted.  This works for a trimaran, tucking the short ama into the hollow beneath the deck, but would be a problem for a Harryproa with the taller leeward hull.  That would place the side of the hull in the water, would angle the mast(s), and might expand the trailering width.

  Looking at the folding method on cat2fold, I'm not sure where all the unwanted weight would come in.  It's really just a beam, cut in two, with a pivot point in the middle and a hinge at each end.  How much weight do you think it would add?  50 Kg?  Not knowing what the normal beams weigh, I can't really estimate.  Masts would always be vertical, as would the leeward hull.

  On the other hand, I think you have a good point: a well-designed trailer could do the trick, allowing you to transport a boat with standard beams, yet without requiring a boatyard lift.  It wouldn't allow you to collapse the boat in a harbor, but it would make transportation a heck of a lot easier.  Plus the boat would be lighter, and probably sturdier.

  $200 a year for storage?  My, that is nice.  Prices keep going up here in Maine as the value of real estate soars.  We're lucky to have bought property up here when we did.

  I don't know if I can swing a trip before October.  When is Bain planning to sail?

       - Mike


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