Matt (or other new owners)
Have you weighed one of the Blades yet?

CARY

Cary,

The prototype first set of hulls weighed in at 25kg. This was the same weight that the timber hulls were. There is a couple of pound saving in each hull just from some process and patern changes without ajusting the laminate at all.

Unfortunately for you dieters, we nevery fully assembled the boat until Sat morning before the Tradwinds, and I have disassembled it and cut open both of the prototype hulls to 1) fix the issue with the 1 dagger board well , and 2) fully inspect all of the connection points to make sure that there are no stress cracks or other issues that may show up later. We were lucky that this first outing was in some rough conditions, so that there was some significant stress put on all of these joints.

I Will have it back together for a test sail next weekend, so we will put it on the scales at that point. Class min is 107kg all up F16. The all glass version should be relatively close to this. Close enough that the platform could be made extreamly close to minimum weight given all carbon options, and some home made reductions for those afraid of diets.

Our goal is first off making a sound boat that is competitive with the best out there. There has been some rumours that we building with a single layer of glass cloth. I can tell you this is not the case, and just the opposite. This boat has become the one I will be racing as well as building. I am not the most carefull person when it comes to using my gear. I need something that is easy and can take some abuse. I know I will drag this across the beach when the wheels are just too far away, and sail up the shore when comming in , and my favorite time to sail is when it is blowing like stink. I have designed the laminate and structure of this boat significantly beyond what is necessary from a pure saling/use standpoint, just becuase I know 250+lb guys are going to be standing on the insided of the hulls when righting the boat, and sailing up onto the beach, and hitting the sides with knees and heads during those out of control days. If you want to sit on the beach with diapers under the hulls and brag about how light you boat is, there is a class for you called the A-cat, and we will be damn near what is min if not at, but the class is still more than the A cats.

All sounds Great. Glad to know you're building a boat designed to last, and put up with the various abuses the sport sometimes dishes out.
Yep, we will climb up on and then stand on the daggerboards, we will stand on the inside and outside of the hulls, and we'll run aground and into stuff with the daggerboards, too. Sometime we just fly through the air and crash our whole bodies on anything that happens to get between us and gravity.
I was asking about hull construction. I'm no engineer, just a monkey with a grinder that gets to fix broken stuff sometimes. You wonder what you're drilling into when we add and remove fittings, if it will hold the stress, will it create a leak or leave a big gaping hole when the fitting rips out. Many cats today are sandwich of glass around a foam layer, like my I-20, some sort of vinylester foam, sandwich hull construction. Supposedly light and strong, but more difficult to repair. Even our hotshot Glass man gets squeamish when working on foam sandwich hulls sometimes.
Also, while all of are concerned that our boats are light enough to race competitively, Only a fool would want to sail on an fragile boat if he's footing the bill for repairs.
Sounds like you're building a fast light boat that will stand up to the abuse we dish out.
Well Done! We needed that.
CARY

I thought you guys may find this interesting :


Hull weights

A-cat about 14 kg / hull

Formula 16 23.5 - 26 kg / hull depending on the design

Hobie FX-one 35 kg / hull somewhere around this figure.

Formula 18's 40- 45 kg / hull depending on the design.

Wouter

I wonder why the pre foam catamaran hulls are often identified by the nick name "egg shells" ?

Would that be an indication on their robustness ?

Wouter

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I wonder why the pre foam catamaran hulls are often identified by the nick name "egg shells" ?





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The answer is stiffness. This only comes from the thickness of the material. The loads imparted on a catamaran hull are negligble relative to the strenght(tension) of the fibers. The failure comes in compression (Just see Altered as an example) To make a hull stiff enough to stand on or any other non sailing related tortures they go through with a single skin, it would weigh a ton. Cores add thickness without significant additions in weight.

M