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 Carbon Boys - Lighten up?

Jon Whitehead

In the odd spare moment whilst attending open meetings, I often take a walk through the dinghy park to check out the latest gadgets and drule at the odd new boat. One cannot help but notice the frequency of use of exotic composites amongst the quicker and mainly newer boats. Further investigation reveals that these composites are usually used where there is both a performance and a weight advantage. It had been a while since I had read the measurement rules so I took a quick butchers in the handbook.

Well I never….section 6 states " total hull weight is the combined weight of the hull, correctors and centreboard……..but excludes sails, spars, rudder, tiller and other gear" Ah ha so thats why theres so much Carbon about. Its not only a technical advantage, it gives a weight advantage too!

This started me thinking " how much unmeasured weight loss does a fully composite boat gain over a run of the mill National 12?" A quick call to Tom Stewart and a few beers with Ian Gore and I started to prize a few numbers away from the elite…

Rudder and stock - Carbon/exotic = 1.8kg, my wood and cast RWO stock = 4.1kg!!

Jib stick - Carbon/exotic = 150gms, wood = 730gms

Boom - Carbon/exotic = 1.4kg, my aluminium RWO = 3.5kg

Sails - Carbon/Kevlar = 2.6kg, Dacron/CYT ( old China Doll) = 4.1kg

Mast - Carbon/exotic 5.5kg ( adjusted to 7.25) my Kappa 8.0 kg

So, there appears to be a "legal" saving of circa 7.25kg and a possible saving of 9 kg and thats without looking at some of the more advanced cordage that can be acquired nowadays or taking into account some of the technical issues that Mike Hoyle brought up at the AGM ( is a mast hung jib stick part of the rig? Etc). Further, most of the saving is at the extremes of the boat ie hanging off the transom or wofting around above your head. If you dont think this is significant, put a bag of sugar on the burgee anchorage and sail a quick beat in a lumpy sea. Notice that the leach is twitching around as much as a fleet of Enterprises at a windless open meeting!

Now the reason that we have class rules is to enable us all to engage in fair competition. Clearly, the introduction of exotic materials has outdated our weight measurement rule to a large extent and a proportion of the fleet has a fairly hefty advantage over the rest of us. Given that most of the carbon boys are in newer, stiffer performance boats the advantage is going to those that frankly dont need it!

I’m not a boat designer but on talking to those that profess to be in that line, I understand that the all up weight of a boat is a critical factor in determining the designs ultimate performance. Clearly a boat with 5kg less weight in it will have a faster response than if it carried that 5 kg. Is it now the time to start talking about the all up weight of a boat ( ex crew of course)?

This approach would, it seems have some very practical advantages:

  1. For those that wish to make the next weight change in 2000, they may mix and match between cutting hunks of mahogany out of the boat ( if there’s any left) and say purchasing a carbon rudder assembly.
  2. The competition would be on a level playing field as far as weight was concerned.
  3. There would be no weight advantage to add exotics to a new boat, therefore pricing may be more competitive.
  4. Amateur builders should be able to come in under the total weight. ( ie build in wood but add carbon spars etc) The perception right now is that it isnt possible to make a one off 12 down to the new weight so a rule change may act as a catalyst here.

Some may say that the rule exists in order that a sail change or a rudder change doesnt necessitate a re-weigh. I cant subscribe to this as weight is weight and to carry less than another competitor gives a clear advantage. Further, once a boats all up weight is established it is relatively straight forward for the crew to weigh any changed gear and make a simple arithmetic calculation to deduce if that change has resulted in the need to re-weigh the boat. In the end the onus is always on the competitor to ensure that the rule is complied with.

So, Shall we say 90 Kilos for 1/1/2000?

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