Where are the catamaran innovations?

[farjoe]

Originally Posted by Gary Baigent

Recent information about the Auckland/Tauranga - line honours and a class record set by a John Tetzlaff 8.5 metre (28 foot) catamaran Attitude, beating in, no thrashing, all the 50 to 60 foot monohulls and multihulls. Check out the construction.
Hi Gary,
Yes Attitude did well. I understand they saw the front coming, reefed down before it hit and were able to keep going. Good seamanship I reckon. Also good because questions had been asked about its scantlings (4mm tortured ply with 300 gsm boat cloth on the outside) and whether it was suitable for offshore. Those questions have now been answered. Good the new owner is willing to take it outside the harbour too. Shame about Catabatic - I guess we'll hear the details in the days to come.
Greg.

do you know of any web site of this or similar boats being built?

[Gary Baigent]

hey Chris
Yes I bet that schooner tri worked well, light looking, has to be fast, low down but large rig. Regarding the Cox's Bay skimmer, it's owned by a friend MG. Watson and he's just got the sails - and we were hoping to screw the last fittings on this long weekend - but raining at moment so setting us back a little. In fact we've had a number of fronts come through with one savage hail storm in the last couple of days and that hit the Auckland/Tauranga fleet and caused one capsize (Catabatic, maybe their name tempted the gods) and much broken gear and some retirements. I thought the crew on Attitude did an outstanding job wiping the fleet of high tech mono and multi designs.
The woody Morris is owned by another friend Mort, a Geordie who has been living in Auckland for decades, that's him slouching along left of picture. Sorry, he loves the vehicle, won't sell.
Farjoe, don't know of any tensioned ply web sites but here is a shot of an early 30 years ago) kiwi tensioned ply Tennant trimaran Demon Tricycle being built.

[hwbd]

Anyone know of a set of plans for a home builder for a powered tri?

[basildog]

G'day guys,
I've just read the last couple of pages (stressed ply construction). Here is a link to building a stressed ply Moth.

http://www.moth.asn.au/download/buil...skiff_moth.pdf I found this very interesting as the patterns probably lend themselves to building something larger.

Just thought someone may be interested.

[ThomD]

Anyone know of a set of plans for a home builder for a powered tri?

Yup, Kurt Hughes has two in his stock folio:

http://www.multihulldesigns.com/desi...ock/38tri.html

Gino Morelli did the Yanmar Endeavour that went trans-pacific without refueling.

http://www.morrellimelvin.com/power/...hp?WEBYEP_DI=5

Newick has done a variety of plans that were sailing boats that would convert to canal cruisers in europe. A thing of his.

Phil Bolger has a power tri, though generally I feel his multi designs are suspicious, the tri looked like it might be worth a second look. (Phil passed away last weekend and his enormous tallents as a writer and designer are sorely missed)

http://www.duckworksmagazine.com/07/...ntam/index.htm

A lot of folding, or demountable tris will do double duty. Like ones that have main beams can simply have shorter beams, and the boat will work under power.

[John in CR]

"Where are the catamaran innovations?"

My question is where are the reefable lightweight wingsails. That would be a real innovation, and shouldn't be that difficult.

John

[Angélique]

Originally Posted by John in CR

"Where are the catamaran innovations?"

My question is where are the reefable lightweight wingsails. That would be a real innovation, and shouldn't be that difficult.

John

K-Designs ECOnomy cruiser

‘‘All new mainsail design, with aerodynamical sleeve and still the possibility for standing rigging and shortening of the sail.’’







http://www.ikarus342000.com/ECOpage.htm

Angel

[DarthCluin]

Actually, if you replace the battens with a short gaff, you have Jim Wharram's Tiki wingsail, as demonstrated by the Boatsmith built Tiki 30:

[Zilver]

Yes, but then you have to attach the stays to the top of the mast instead of the 3/4 up position.....I think the designer tries to work around that.

Hans

BTW the Wharram wingsail works very well from an ease of use perspective : you can hoist the sail on nearly all courses, it drops quickly and smoothly, low hallyard loads, etc. If it's as efficient as Wharram claims I cannot say, the tiki's are not exactly race-monsters.

[ThomD]

The thing about the KD rig is that it is easy to raise the mast due to a short spar height. Both the TIKI Wingsail and the KD are designed from traditional rigs for ease of home building.

I like the Wharram wing sail, but I have heard people who sail them speak of a tendency for them to jam when being dropped. If I had one I would consider using a tied on sail for heavy weather. One looses the advantage of the luff fairing the spar, but in certain circumstances that might not be a big loss.

[ImaginaryNumber]

Originally Posted by John in CR

My question is where are the reefable lightweight wingsails. That would be a real innovation, and shouldn't be that difficult.

Bertrand Fercot has developed a "Swing Wing" wingsail which he is using on two Wharram Tikis, but which are different from the Wharram wingsail.

http://wharrambuilders.ning.com/group/junkrigged

http://wharrambuilders.ning.com/prof...tiki-30-n119-1

[BigCat]

Originally Posted by ImaginaryNumber

Bertrand Fercot has developed a "Swing Wing" wingsail which he is using on two Wharram Tikis, but which are different from the Wharram wingsail.

http://wharrambuilders.ning.com/group/junkrigged

http://wharrambuilders.ning.com/prof...tiki-30-n119-1

Bertrand has been modifying his rig which started as a Swing Wing. The Swing Wing rig didn't have an airfoil shape, and Bertrand is now improving his rig by making it more airfoil shaped. A number of people have independently originated this kind of rig, which is a fairly obvious evolution to those who are familiar with the hinged junk rig. The hinged junk rig is the junk rig with a hinge added to the boom and battens to give the sail camber. The hinge usually has a very limited range of motion to give 7 or 8% camber.

The next step forward from a hinged junk rig is to put the mast inside a foil section. This is discussed from time to time on the Yahoo junk rig group, http://groups.yahoo.com/group/junkrig/ . My design can be seen at http://bigcatcatamarans.com . This rig should combine the aerodynamic features of a wingsail with the unbeatable handling characteristics of a junk rig. It is also very economical compared to the usual - the only drawback being the lack of provision for huge light air sails - so this is an idea for the kind of cruisers who normally eschew spinnakers and huge jennys. These rigs are normally designed to have an extra 20% more working sail area than a sloop of the same size.