p.s. again. anyone can carve a chunk of ultra-HIGH density balsa (320 kg/m3) into a shape. no challenge in that.
Oh yeah? Well let’s see you shape a balsa rudder with a random orbit sander. I only shot it across the room twice. 
It’s almost the desired shape.
I’d love to try one out for you. I even have a footy in need of a new rudder. Did you know that balsa can break?:tapedshut
random orbit sander eh? jokes.
i just released proto#2 out the mold. it’s my lightest glass cloth with an epoxy matrix. i’m thinking about some carbon unis to stiffin it spanwise, but only after i test this one. i could send it to you to test if you’d like?
we’d just have to figure out shipping. i reckon padded envalope/ basic ground. any way, it’s saturday morning and i got alot of muckin about to do.
made a test lay-up out of the flash. used some old hetron with graphite powder, and a layer of 5oz. started the keel plug as well.
here’s another.
and another.
some more.
and yet another.
keel plug started
the other half
Nigel, for reasons I’ve explained, I am very sceptical about this working - but your workmanhip is so beautiful that I can’t help hoping it will!
i’m guessing your talking about the hull not having enough displacement to carry the stock, box-ruled footy rig, and radio equipment?
can it not use lighter running / standing gear, and r/c equip?
or add displacement to the hull shape, so it does?
in theiry, if the shape of the hull is made to go at it’s best at the designed wateline, and this same shape carries all of the boat’s weight, at this line, it should work. am i wrong?
Nigel, I’ve just be doing some quite unrelated calculations and discovered some interesting things.
Scaling a an Open 60 weighing 10 tons gives us a weight at Footy size of about 143 g. On conventional Footy technology, this is wildly impractical.
However, if we use the latest lightweight electronics, assume that ‘restricted to 4 AA batteries’ in the rule means ‘no more than’ and use a carbon tissue/polystyrene sandwich structure for the hull, we can get a boat with about 190 g displacement - with a 50% ballast ratio. This is much heavier than the scaled Open 60, but it is at least a boat that operates in the same general kind of way and in which the Open 60 type of hullform might have advantages.
I know you say that carbon tissue is rubbish: I agree. However, short of laying on individual rovings, it is the only form I know of in which you can get light enough carbon ‘sheet’. Your cloth will be stronger and have a higher strength to weight ratio - but it will be heavier in absolute terms and the increased strength is not doing anything very useful.
As I said, humble pie!
like i’ve stated, my hull is styled after the 60. i also mentioned different displacement in the hulls design.
the over-all weight of the gear could be lowered, or the hull volume /displacement could be increased.
tissue aint rubbish, it has it’s use. the biggest thing with composites, is their commonly used in the wrong applications. laying individual rovings is very effective for the use of stiffining a structure. it is good to use something that is overly strong, the reason is that one could use less of it (lighter weight) to achieve the same strength, or, have the same weight as the lesser material, but much more stronger part. it goes both ways.
i had some strawberry tarts with my tea this morning, but no pie!
final hull plug ready. i’ll start the mold monday.
another plug pic
and another one
and one last. just has to be polished, and semi-permanented, then on with the graphite.
just started the canopy/hatch plug. layer of tooling sauce in the deck-plug flash.
hatch plug in the rough.