Tasarの製造に関する問題

 Hi all, so I am writing to you in the light of a few conversations since I wrote what is below.

All those conversations have been in the same vein and we are probably at the point where we need to consider doing a new plug.

The advantages of a new plug if the 49er and 29er are anything to go by is a reduction in manufacturing costs due to increased alignment, plus the existing moulds are just tired.

These can be very minor, in the case of the 29er the section 600mm back from the bow, was less than 1mm off-set to one side, but the ramifications in the build process from that and other discrepancies meant that a previous 29er took 3 tone of vacuum to pull together whereas a boat out of the new tools "fell together" to the point where we had to put 8mm blocks between the laminates so they did not "overly clamp".    No Vacuum needed!

I think that you should all have a good look at the points below and consider what you want and what you don't and we should embark on a process where we commission a new set of plugs to be CNC milled.

Whereas the 29er and 49er we tried to stay within +/-0.5mm and that cost $20-30k in Phototelmotrophy and NA design work, that we should consider +/-5mm tolerance, avoid all those detailed costs and simply "throw a T2 design".

What that means is we accurately measure an existing Tasar, we then average each side and come up with a mean, but allow a +/-5mm range to fair the lines in.

Fit a new deck, etc etc.   Make new plugs, then moulds and go from there.

We can go green.

We can go lighter but carry lead for an agreed period (like the I14 - A14 transition)

With the ever escalating price of aluminium, we possibly need to look at FRP masts.

Simple dagger rudder stock.

yad yad yad.

Not sure who this should go to, but if you want a class in 10 years time, this should probably be spoken of at the AGM in Seattle.

                  jB

Julian Bethwaite
Sydney Australia

+61 413 74 2949 Mobile

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On Mon, 29 Jun 2020 at 10:28, jbethwaite@gmail.com <jbethwaite@gmail.com> wrote:

So Chris, and I have included everyone else because it's across the board,

The area's that you can and in some cases need to address, from my POV are

#1 Going Green.      This may be mandated in the not too distant future.    It has to do with

a) reducing styrene emissions   (we can probably avoid infusion with the Tasar (we can't with the 29er))

b) using less resins (which are toxic)   

c) using green materials (Flax, Basalt)

d) using pre-loved material (PET foams)

#2 reducing weight of the boat.

a) sensible re-tweaking of the PET/Flax/Basalt combination can lead to really tough but lighter laminates (this would be 5-8kgs probably, I have not done the maths)

#3 Carbon mast

a) inertia drop

b) sail are increase (you have to to compensate for #3 a) )

c) reduce complexity (no diamonds & no rotation lever)

d) Synthetic rigging (simplicity and longevity)

#4 Sails

a) what I call 2d sails, so mono film, cross cut and cost effective sails.

b) other aerodynamic advantages   (Cuff luff and winglets)

#5 Rigging 

a) so beyond #3 d) (which is standing rigging) looking at all the rigging systems

(need to stress I am NOT advocating a RAM vang)

#6 Foils

a) you would be far better served using 29er type foils sections and dagger rudder stock.

#7 Marketing factors.

a) retro-fittable and transition capacities

b) new image.

       That's me for now, if I think of anything else, I will add it.