Hull weights

Most A-cat hulls weight between 13-17kg. A Taipan 4.9 hull weights around 23 kg. I am curious what are average current hull weights for popular classes like

F18

Tornado?

I assume the Tornado does have a minimum platform weight while the F18 has (like the A) only a minimum total weight?

But what is the weight of a bare hull (including fixed fittings but no daggerboards/centerboards attached)?

The Tornado became significant lighter over the years but does that mean that a current Marstroem hull is noticeable lighter (surely it gained stiffness) than a Tornado hull build 20 years ago?

How about these develompents in the F18 class?
Does a Tiger hull weight in similar than a Capricorn or Nacra one and is this still similar to the hull weights of the early dominating but nowadays unpopular Dart Hawk etc...?

Curious in some numbers... and just in case you think you hulls are h e a v y, I might publish the hull weight of my 1982 Supercat 20 too <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

The hulls that are built more cheaply will generally be heavier for a given length.
A tornado hull from 1987 would only be alittle less stiff than a marstom hull since there were some honeycomb tornados then. even the gugeon cedar hulls were quite stiff. the tornadoes of the 60s and 70s were much less stiff than today, but the weight was the same. unless they changed the weight over the years, but one design classes are not supposed to do that. the t hull has always been the same weight since the first boat. that # slips my mind but it may be around 70#
the supercat hulls gained lots of weight after the first 50 boats when the company was sold to boston whaler. less care given to appling the liquid resin=more resin in the lamination.
an 18 foot acat hull will be lighter than an f18 hull for 2 reasons mainly. 1-less reenforcement and bouancy needed.
2-acat can use more exotic building techniques, unhindered by the f18 rules.
i imagine the dart hawk was built to the same rules as current formula cats and therefore had hulls weighing aproximately the same as a current boat.

F18 Class Rules

B.1.3 MINIMUM WEIGHT

1.3.1 The minimum weight of the platform is fixed at 130 kg
1.3.2 The minimum weight of the boat ready to sail is fixed at 180 kg
1.3.3 A corrector weight of maximum 7 kg may be used to satisfy these two conditions. This corrector weight shall be fixed to the outside of the forward beam on the starboard side and shall be removable for checking.

FYI, the Capricorn platform is build heavier than the Tiger but has a much lighter rig to meet the 180 kg whilst reducing weight aloft.

I got the following weights from several sources:

Marstrom Tornado kg 41,5 (+/- 0,4 Kg)

F18 Kg 43-49
(Capricorns of the high end of the range/don't know about the Infusion).
However it was quite often measured a difference of up to 3 kg between two F18 hulls of the same builder.

F18HT kg 30-33

The tornado weights have not changed much over the years. Everything I have read indicates that the hulls had to be less than 100 lbs to build to minimum weight. The minimum weight has really not changed over the years so the hull weights have been relatively consistent. The success of Marstrom has not been because they are lighter than the rest, it is because they are stiffer and more durable than the rest. This done by using a thicker core material, autoclave pre-preg S-glass (which reduces the resin content of the layup giving more glass per sq. ft. of the hull) and really understanding the loads and where to re-inforce the hulls.

I used to think you could get close to the Marstrom build quality with less exotic techniques (vacuum bagging and slightly elevated cure temeratures), but the reality is you cannot. Maybe you can get to 90% but you will not quite get to 100%.

I'm jumping in early here. You wouldn't want 5 replies without a F16 sailor stick his oar in. I went to see my new hulls last Sunday and they weighed 22kgs or 48.4lbs each. Minimum all up weight for a F16 I think is 107kgs or 235.4lbs.

Single handed boat is 104kg, 2 up is 107kg

Alpha Omega F14 hulls with fittings - 16kg's
All up minimum sailing weight (less only the crew) - 75kgs