Bigger thickness in walls is something that has not been discussed at all here. If there has been such changes then these should have been told in advance so that people entering class would know about these things. All available alu mast data is based on original Taipan (I guess?), now if things change and it would have been made to public we wouldn't be having this discussion.



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So you are saying it's ok to lie how good alu is when comparing to carbon and when reality hits, you tell that you can always sell your stuff with loss and get better? I would say that in general this is not a best way to welcome a new member to the class, but then again my boat is not class legal unless I eat 10 kg's more, so I don't count.
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Anyways I could be changing mast but I'm not too keen on losing money on six times sailed mast. I based my decision to data posted here on internet forum and what was written in the plans. With my current knowledge I would most certainly do things differently and it's not always nice to learn through hard way.

Valtteri,



I dont know if there is anything else to say. I dont think there are two dies and would be surprised to hear otherwise. I dont think there is any ill will or hidden agendas behind the weight of the masts you and Gato got. Any advice supplied to you and Gato was surely all in the best meaning.

I too don't think in hidden agendas, but I think that these should be mentioned. Whole situation is different if you have a boat next to you and you can test it yourself (with older mast? <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />) but for people basing their decisions on numbers it's unacceptable that they don't match. In this thread alone we have lot of hear says, so let's get our measurement data somewhere public (like T's mast data).

Most certainly should have been told here that if you weight less than 85 kg's (used to be around 80) use righting aid or get carbon stick. I honestly thought that I could right my Blade unaided with that alu stick.

Stewart said the boffins are working on the issue, so now we sit down and wait

Dependents on where you have the die made (China, USA, EU). Can be as low as 1000 Euro's (China), sadly problem Chinese extruders is that they won't extrude wallthickness that are less then 2 mm and for a mast you really want 1.6 mm (25% weight savings relative to a 2 mm wall mast).

Let me put it this way : having a new mast die made is something that is within reach of the F16 class and its current membership if we are willing to all invest a little. The same is true for other stuff like alu beams. Other classes like the Mosquito's (I believe) have organised mast and beam production inside their class structure and every person can order himself a set (or more) from the class organisation.

I still believe that this is something we need to look at as a class. The superwing is an excellent design but it can be improved upon slightly in one or two areas. It could do with a little more side to side stiffness and having the walls be a 1.6 mm again would help as well.

It is possible if we all will it !

Wouter

Actually a die can wear out when it is used often. Also there is some naturally spread in wallthickness when the proces of extrusion is not carefully controlled. An offset of 15.6 % is certainly not negligiable but it is not outside of the realm of possibilities either.

It is my suspision that the die is aging and that a replacement maybe in order. But again that is my judgement of the moment on the info I hold now. It is not my final judgement yet.

Wouter

There really isn't that much difference in the way of SAILING PERFORMANCE.

This is a totally different topic then RIGHTING ABILITY that is currently being focussed on.

Wouter

In all honesty, I'm aware of the price John Pierce had quoted for the blanks when a bunch of them was ordered in one go by another builder. That price quote was higher then the 500 pounds quoted earlier in this thread. I'm not saying that the 500 quote is wrong but my information does not confirm it is true or that it is likely to be true either.

Personally, I think too much rumours are being flown on this forum. 90% is simply not true or is a very warped version of real situations.

I admit that I can wrong from time to time but I've never intentionally misleaded anybody.

Wouter

There have not been any intentional mast wall thickness changes.

At this time we are still looking for the cause. It can even be that the extruder decided on a different extrusion speed as to be able to pump out more extrusion per hour and optimize his earnings. The builders and myself are just as much behind "the curve" as the customer like you are.

That is why I want to get to the bottom of this weight difference issue as I have said in private communication.

Wouter

If I may make a contribution. I have an aluminium wing mast originally supplied by AHPC, however I did buy this one privately as a blank section. At some time when I were weighing my hulls on the bathroom scales, I decided to grab the mast and weigh it, without any great accurancy, but within reason, it was 14kg.

Originally the mast came from this die I believe (do not quote me on that) and then a heavier section was also available suited if sloop rigged. A batch of masts came from the lighter section die, that were very inconstant, in fact I know of one person who is multiple national and state champion that went to AHPC, went through the entire rack looking for a mast with good bend characteristics of the entire rack, he found 2 'maybes' and took the best, only to return it not long after and stick with his original mast.

I have what would be called an original cat rigged section and the only masts available now are the heavier sloop sections. And it has been recently moved at the Taipan AGM to not allow more newly registered boats to have the lighter masts, to have a level playing field, because the owners of these masts were selling their boats without mast or with a new section, and carrying over the mast to their new boat.

Regards

I take this personally so I will reply to this once more.

I don't know how much you weight valtteri so I never took that into account. And it is my honest opinion that there are several righting aids available to allow ANY F16 sailor over 60 kg to right the F16 singlehandedly in a quick and safe manner; irrespectibally whether it is a alu or carbon masted F16.

I know from personal experience that the F16's with alu are the second easiest boat to right singlehandedly. Only the A-cats are easier to right and I have said on numerous times. You try to right a Hobie 14, Hobie 17, Hobie FX-one, Nacra 5.0, Nacra 500, Inter-17 or any similar craft singlehandedly and you'll confirm this experience.

It all stops somewhere; in no wind and flat water a modestly weighted skipper will even have to work to right an A-cat.

Many of us have commented on how good alu is in the way of sailing performance and yes indeed righting. Again, the F16's are the second most easy to right beach cat EVEN WHEN FITTED WITH ALU. There are about 100 design more difficult to right and only 1 easier. That in my book makes it an excellent design. Now some people may dream about being able to right a carbon rig with only 40 kg on the righting line but that is really not going to happen with a 5 kg mainsail and some 2 kg of water sticking to the cloth at the tip.

Sailors like PTP note how they (73 kg) can right the boat when winds are above 10 knots and they are certainly not lying. Implying anything different is just disingenious.

Another argument revolved around min boat weight and how the alu mast is stuffing that up. The numbers I've been told puts you guys about 120 kg. Pardon me but that superwing mast is not guilty in adding 13 kg to the whole boat. Typically it is 4 kg and maybe you guys have gotten exceptionally unlucky and it is 6 kg in your cases. That still leaves more then halve to other causes.

I still do advice the aluminium mast to people interesting in the F16 class for the following reasons :

-1- it is the most inexpensive F16 mast at this time
-2- it holds up very well under general accidental abuse
-3- allows modification of systems on it by the owner (moving blocks and cleats about, without extensive work like laminating reinforcements)
-4- most development of sails so far has been done for the alu mast; several sailmakers now have "off the shelve" F16 mainsails that are well behaved and fast.
-5- The alu mast has good rightability that is second to one only (A-cat).


I think all these reasons still hold and carbon masts made by fibrefoam or Saarberg are still quoted at 3000 Euro's (1500 pounds). Stealth Marine has always been cheaper then these well known carbon mast builders but I would still like to see an actual and official quote of 500 pounds before I believe it. In the USA carbon mast made by companies like Hall are even more expensive then Fibrefoam or Saarberg. Australian Composites mast are comparable to Fibrefoam and Saarberg last time I checked.


What I'm saying here is that I or other like Phill would never ever intentionally mislead any new class member like yourself. Everything we said and wrote to you was believed by ourselves to be both true and well-balanced. Now indeed we are only human and so we can make unintentional mistakes, but I really don't think any of those were made in your case.

I do believe that you an Gato expected alot more from the F16 then we realized and are now hurting because of it. I say that it may be wise to finish the crafts anyway and actually sail it, then find yourself a Hobie 16, F18 and an A-cat and test sail those; don't forget to raise the mast on the F18 and lift all boats onto the trailer. Also make sure you ones drive the A-cat downwind with your partner sailing the F16 down alongside it under spinnaker. Then look up all retail prices. You'll recognise the differences soon enough even when your boat is 13 kg overweight to the F16 minimum.


We are all making far to much out of pretty minor things here.

Wouter

I don't think AHPC ever had two dies.

They did sell a lighter 1-up mast and a heavier 2-up mast, but the lighter mast was made by putting the heavier mast in an acid bath and removing part of the wallthickness. Such a proces is difficult to control and that would also explain the large differences in behaviour.

Wouter

Well, this is indeed true but we also have got to look at the limitations here.

We are an owners driven class. Officials are all volunteers who do not earn a single dime on the class efforts. As a matter of fact more often it costs the officials money they graciously donate themselves. AHPC is not to bothered by any die-wear as evidenced by the Viper F16 weights so far. If anything the extra wallthickness is considered an additional "fools"-margin when handling the spi.

AHPC owns the die and the other builders, agents and dealors can their masts from AHPC authorized production runs under a "general F16 class usage" agreement I brokered back in 2002.

Assuming that the wall thickness of the Superwing masts have increased from 1.6 mm to 1.85 mm by a die wearing out or because the production proces parameters were changed then there is little we can do at this time. AHPC is the party that can persue solutions, not us. That is unless we as a class buy our own die and enter into a production agreement with the extruder ourselves.

The latter thing is a serious possibility but not without the class creating some revenue streams for itself, ; like membership fees. Several of us have sunk several hundred to several thousant euro's into this class and buying a new die is just a bridge too far for this small group of dedicated volunteers. That is why the other project (=new alu mast design) was put on hold. Lets not forget that the F16 sailors have been stuck on a "free-rider" mode for the last 7 years now. All class business was performed on a free-of-charge basis.

So I'm not sure what the boffins can do at this time without some serious commitment from the F16 sailors to supported the F16 class financially.

Wouter

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You should because that was meant to be personal. The good things with alu extrusion is that it's really cheap and the result fairly similar every time. That still doesn't make it better than carbon for every use and as a engineer you should probably know that.
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I started this whole thread because I really wanted some useful info (available at first page, without mast measurement data though, before we went to sidetrack) and let people know that they should be careful when doing their decision (at least ask weight before ordering). Fact is that we got fat spars and most likely someone else will too.

I really believe that if someone would have posted something like this little bit over a year ago it would have helped me. Only way of not having these discussion is to have real measurement data posted somewhere, then people can directly compare what they got to others.

There is, let people know about it and put all of our measurements online. I guess that at least AHPC knew, so why that wasn't made general knowledge?

If that is the case, who knew besides AHPC?? I did not. Perhaps ask AHPC about that if that is the case..

Valtteri, can you clarify what you are asking for - do you want data on existing superwing weights from current owners to gauge variance and change over time, or are you looking for production data from the extruder?

Buying a new die seems worth thinking about to me, though I'm not sure class membership fees are necessarily the best way to handle it - Stealth owners may not be too enthusiastic. But I would consider ponying up a little cash for the good of the class if there were enough others involved. Just thinking out loud... what if the cost was split three ways between VWM, FCA and the class?

If the class wants to commision a new die I can help arrange a good price(we use a lot of ali).

What righting systems are sub 80kg sailors using at present?

A tornado with a carbon mast can be righted by one person without a righting rope.

Sorry the DS16 is round bilge and will be resin infused carbon in CNC milled female moulds, because, Ironically this is the cheapest way for me to build it.