There is quite a debate on the F16 forum about "mast tip weight" and Alu v Carbon masts.

Any opinions? Seems to some folks carbon is the cure for everything. I'm not so sure.

btw- I think the British army is going to start making tanks (partly) out of carbon. That can't help world prices.

Surely it's the US defence requirements that are pushing the price of Carbon......

Oh for the love of god do we have to do this here! Keep it to sailing please!

Carbon is better than aluminum, for the weight savings alone.

Putting a weight in the tip is just stupid. You either allow carbon sticks unrestricted or ban it!

Dude,
It depends a lot on what you want.

Eric

Aluminum masts, etc are expensive initially because the cost to build a die is high. Mast blanks must be ordered in large groups to keep costs low. It costs a lot to change mast profiles ie buy a new die. There are definite quality control issues with aluminum masts, i.e. different weights etc. They need to be anodized.

[quote
I'd like to see the F16 class grow and still keep my costs down.

For me, the weight and performance are ideal. I'd be happy to freeze developement at this point. At the same time, I fear that would be the death knell of the class.

Hence the debate.

Dude,
It depends a lot on what you want.

Carbon fiber epoxy composites have several advantages when used properly.
1. Weight savings. Prepreg Carbon epoxy is about 40% better strength to weight then aluminum. Sometimes this can translate into a significantly lighter part. You start running into wall thickness issues and buckling problems in some cases.
2. The carbon can be applied along any axis allowing the mast bend fore and aft vs side to side to be changed. It can be modified if it is not quite right in the first place. Ie start with is slightly soft and add uni carbon to get it exactly how you want it.
3. Carbon parts can be repaired with reasonable success.
4. It lends itself to home building techniques
5. It can be the difference between righting a boat unassisted and needing assistance.
6. Better reproducibility from part to part if quality control is high.
6. It looks cool.


Aluminum masts, etc are expensive initially because the cost to build a die is high. Mast blanks must be ordered in large groups to keep costs low. It costs a lot to change mast profiles ie buy a new die. There are definite quality control issues with aluminum masts, i.e. different weights etc. They need to be anodized.

Downside to carbon parts.
1. The cost of carbon parts can be much higher. Masts, etc are built in an autoclave and cured at high temp and 5-6 atmospheres of pressure
2. Material availability is a problem today
3. The failure mode of carbon is often catastrophic

Eric

The couple of pounds on the tip means

"1.4.5 The weight that is measured at the mainsail hoist height of a mast lying perfectly horizontal with its base supported at the bottom edge of the mast section is referred to as the "mast tip weight". The minimum mast tip weight of a fully fitted mast, excluding standing rigging, is set at 6.00 kg for reasons of seaworthiness and to guarantee fair racing."

This is confusing to me, but I don't think any weight is actually added. Rather, a mast is either legal or it isn't, when weighed in the manner mentioned above.

Surely it's the US defence requirements that are pushing the price of Carbon......

>December 17, 2002
EU Imposes $83M in Fines for Price-Fixing


BRUSSELS, Belgium (AP) - The European Commission on Tuesday fined 11 companies $83 million in two separate price-fixing scandals involving graphite and spices.

In the graphite cartel, eight companies were assessed a total of 60.6 million euro ($62.4 million)for violating EU competition rules between 1993 and 1998.

The Commission said that a two-year investigation found that the companies held regular meetings to divvy up the market and keep prices at inflated levels. Specialty graphites are used in everything from engineering to electronics.

Germany's SGL Carbon AG received the highest fine of 27.75 million euro ($28.57 million), while Japan's Toyo Tanso must pay 10.79 million euro ($11.11 million).

Other fines levied include 6.97 million euro ($7.18 million) for France's Carbon Lorraine SA, 6.97 million euro ($7.18 million) for Japan's Tokai Carbon Co., and 3.58 million euro ($3.69 million) for Ibiden Co. and Nippon Steel Chemical Co. also of Japan. Another two Japanese firms, Itech and Intech Inc. were fined 980,000 euro ($1 million).

SGL's fine was the highest ``because it was the ringleader,'' the Commission said, while the other companies got reductions in exchange for their cooperation in the probe. U.S.-based GraphTech International Ltd. was given immunity ``because it revealed the cartel,'' the Commission said.
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. . . I hope this is a constant trend as if it continues it will completely obsolete any argument between carbon and aluminium . . .