Steve,

>>Thanks for clarification on cost of carbon in hulls vs cost of carbon beams, it`s more the labour cost of making the beams strong & stiff in certain areas, more than the cost of material, which drives the cost up, if I`m understanding you correctly.


(private sailor) That is the understanding that I have ; combined with the low turnover in these specilized parts. Low turnover means big margins on top of material cost to account for tooling and expertise.


>>If the general consensus is that the advantage of having carbon beams is only fully realised when they are glued in, stiffening the platform, then a rule prohibiting beams from being glued in should suffice, and I would have no objection to carbon beams being allowed.


(private sailor)yes that would be a fair descibtion on the assumptions you state. Hence two approach to split up the proposal in two different votes.


>>I agree with Darryl, no need to outlaw a material that may become the industry standard in the near future. My point on the carbon hull issue was that if we allow full carbon hulls, and carbon masts are allowed, why restrict the beams in material ? The boat still has to conform to the min. weight of the class, it just allows the builder more control over WHERE in the boat to place the weight.


(Chairman) The current low weight of the F16's makes significant redistribution of weight practically impossible. We are only 30 kg heavier than A-cats and we put the platforms under loads at least twice as high, sometime 4 times as high due to heaving a jib and a spinnaker. The jib and spi gear themselfs add at minimum 8 kg to the setup. Any realistic carbon mast for F16 must weight 4 kg more than an A-cat mast. Meaning F16's have only 20 kg to beaf up the platform to withstand the significantly loads due two the sailplan, doubletrapezing and the extra width. Contrary to common beleive ; this is not alot of margin.

For this reason I estimate that the benefit of redistribution is very limited if existant at all.


>>The problem I see with this is that it WILL eventually make the option of home-building in ply obsolete, probably sooner rather than over a long time, since keeping weight out of the bow & stern & centralising it is far more critical than how much the boat weighs, and influences pitching moments


(private sailor) Home building in ply was going out far more because of the limits to the hull shape one could build this way. Phill solved this problem. I really think that your fear is splitting hairs when compared to other far more dominant factors



>>far more than crew weight, which you can place where you want it on the boat, anyway.


(Chairman) Not correct. Crew position is fully determined by wind condition and seastate. Typically when there are enough waves to possibly make a difference when redistributing weight the crew is at the back of the baot compensating for big wind or negociating chop.

In light airs the crew is far forward to level the boat but here the water surface is almost always very flat making weight distribution differences unimportant.


>>The mast rule is quite a good way of controlling an arms race, by having a mast tip weight you have ensured that a carbon mast has no real weight advantage over an aluminium mast, so perhaps a min. weight limit can be set for the beams which would keep things in check.


(Chairman) won't be a very effective rule as carbon beams are hardly any lighter than alu beams. The gains are stiffness and the fact that you can glue them in. Weight saving are negelectable.


>>While making this point I must admit that I prefer a setup with very few, simple rules that can be adhered to quite easily, lets not get bogged down with one-design-minded regulations.


(Privare sailor) to that I agree personally.

Wouter