Jake,
>>(I thought the "Blade" was only an F16 project).
It is both.
Blade started out as a F16 design and that is the one that two companies are trying to build commercially. Then the unique scaling relation of the F16's to the F18's was used in reverse and the Blade F18 was designed. So now the Blade design line encloses two models; one F16 and one F18.
And this may not be the only design to have travelled this "scaling" path. There are rumours of one more design doing it in 2 years time or so.
>>One design, class, or formula racing aside, what has modern construction methods done for me and my F18?
It gave you a boat that will run circles around a Prindle 18 and Hobie 18, designs of the late 70's. To give you one example. Now maybe F18 is not the best showcase of technology, despite its progress relative to older designs. However there are other designs that show what technology has done over the last decades. A-cats and 100 kg doublehanders with F18 performace are the result.
>>I know Wouter built his own tortured ply F16 and I imagine it's competitive.
The boat maybe just that, however I'm not sure about the crew sailing it !
>>Is my boat that overbuilt?
A little.
>>Is the foam core molded construction cheaper to manufacture?
Good question. I may well turn out that a all glass F18 hull is cheaper, easier to build and better in performance. God knows that the F18 class minimum weight is high enough to allow such a construction. Afterall both Capricorn and Blade designs are made using cores that are much heavier then foam and come out at minimum. This construction allowed AHPC to put the bridle much lower on the baot thius lengthening the jib luff, without worrying about stiffness and strength.
More and more I find that tradition is the deciding factor in much boat building and designing. I for one don't expect ply/epoxy to be any heavier than glass/epoxy as a laminate.
>>Does it yield a stiffer platform?
Good question. Foam is all about relativety. You can often get a stiffer platform for a given weight. However this is not the same as saying that such a platform is stiffer in absolute sense. We all know a tube has a superior stiffness/weight ratio but the solid staff of the same diameter is still stiffer in absolute sense.
Now if class minimum weight is high enough than a solid skin hull may well be stiffer and stronger without any performance related drawback.
>>Does it last longer?
Foamed hulls dent for example. There is not much bad I can say about solid laminate hulls from a contruction point of view. The material stresses are lower because there is simply more fibre to carry the loads. Also you have much less delaminate risk that is associated with the boundery layer between glass and foam. All that sort of stuff.
How knows, we may be in for a surprise.
>>Perhaps it's in the economies of scale - foam core composite construction yields a more consistent and cost effective way to manufacture higher quantities of a hull.
That may be true but with resin infusion and improved vacuum curing these advantages may be out dated by now.
>>Complex shapes are easier to produce (Phil may argue that point).
Yes but foam less hulls are even more free in shapes than foamed ones. Afterall you need to curve the foam as well and that it a big factor as well.
>>What do you think it is? Would it be more expensive to manufacture 20 tortured ply Tiapans or 20 molded composite versions?
To produce 20 ply hull is definately more time consuming and probably more expensive when a certain minimal production demand is reached. But then again, sailors pay top dollar for glass boats as well.
Wouter
