Mast weight and rightability

Hi all,

I would like to ask you if you could tell me your mast weight and if
you are using righting aids when sailing 1up? Of course skipper weight
would be helpful to scale your answers to my own weight (76 kg's
nowdays <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />).

Reason for this question is that I finally managed to arrange proper
weighting of my alu wing mast. My mast weighted 18.1 kg's (with
internal dh and mast foot), rest of the stuff was weighted separately
and were 4.1 kg's (i.e. spreaders, diamond wires, trapeze's stuff and
standing rigging). Tip weight was 8.5 kg's without spreaders or
diamonds. I think that it was discussed some point that wall thickness
was made bigger in extrusion but difference in weights were not posted
here and my mast is not a special case as Gato weighted his 18 kg's.

From the top is my head my, mast fully rigged but EXCLUSING the standing rigging (= forestay/sidestay) but including halyards etc (as the mast should be measured under F16 rules) is 21.7 kg. My tip weight incl. all that needs to be included is 8.3 kg.

My mainsail is about 1 kg heavier then the newer mainsail almost entirely because I full 100% glass battens and those weight alot more the fibrefoam battens.

I can right this rig unaided (righting line) in any conditions incl very light winds and flat seas. The latter is the most difficult to right a cat in. I weight typically 90 kg or just under it. Halve way through the sailing season I'm typically between 87 and 89 kg. In some wind or waves I can right the above rig significantly easier.

Wouter

[quote]Hi all,

I would like to ask you if you could tell me your mast weight and if
you are using righting aids when sailing 1up? Of course skipper weight
would be helpful to scale your answers to my own weight (76 kg's
nowdays <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />).
G'day Valtteri
I sail with a mate who weighs 75 kgs and he use's 2 cloth shopping bags(they would hold about 6kgs of water each)he has them tied together fills them with water throws them over his shoulder and he can then get the boat up,if he doesn't use the bags he can't get the boat up at all,
Hope this helps
Richard

I'm 93Kgs and have no problems righting my Blade without assistance. I have not weighed the mast so I can not help you there. As I get serious about better race results I will start to chase numbers. I have a lot of learning to do before incremental weights are going to make a difference.

Cheers,
Neville

I am 73kg or so and can't right my boat unless there is maybe 10 kn of wind (maybe 8ish?) without some help from someone else or an apparatus. If I weighed 7kg more or so I don't think i would have a problem.
never weighed the mast though.

So let’s take a closer look at the case. If we have an 8 meter spar of 20 kgs and suppose that they are evenly distributed that means the centre of gravity at 4 m it would give us a righting moment of about 80kgm. If my CG is set at 1 m with my 75ks I’m fighting a loosing battle. If on the other hand we had a carbon spar of just 10kgs we would only need 40 kgm to bring this thing up.
So folks it has been suggested before and I take a risk to get banned, but it’s time to put your things on the bathroom scale and see what you are playing with. The naked spar should not be more than 15 kgs if you sail High Performance, otherwise you are sailing Heavy Problem.

Doesn't that make it illegal for you to race single handed? How many other people are in this situation?

So it takes around 80 kg's skipper (+gear) to right your boat. It would be interesting to know if that's measured with older light spar or with newer heavier mast.

Btw, I wish that we would something similar like T's mast data available online that would have helped us.

It’s maybe a little bit more complicated, so if somebody has the hydrostatics for a F16 it would be nice to have the GZ curves for the both cases. It’s affecting a lot more than the righting of the boat.
It will also affect the capsize angle, so a heavy mast will get you into the water a little bit earlier. Me included we are 3 to small guys for the moment on this thread

I'm only 70Kg guys - so you'll understand why I like the fact that the tipweight of my Stealth carbon mast is 6.6Kg and I can right the boat unaided in all conditions. I do have to go out onto the tip of my centreboard if the wind is light though.

I can not speak for Valtteri, but what I am after is a little bit more transparency in stead of protectionism. If somebody wants to buy or build an F16 he should be supplied with adequate information. I’m almost certain that Valtteri and I would have preferred to put the extra money needed to get a Stealth carbon mast and to be able to sail safely one up as it was the problem of crew that did us make the choise. There is also another thing; building away those extra kilos is not possible, and you end up with a fat one.

AFAIK John P charges around £500 for a blank carbon mast. Is that what you mean by transparency?

You make a modelling error. IF the above assumption is true then you would also have AT LEAST 10 kg of tipweight which we know you don't. Even if the mast is 8.5 mtr as the F16 mast are then the tipweight would still be at least be 9.4 kg.

In fact the tipweight is all we need to make the righting calculations.

The minimum tip weight for the F16 carbon mast is 6.00 kg, the Superwings are in the range of 8.0-8.5 kg (Valtierri's is the heaviest I know of so far. This means that the difference in righting weight between the carbon guy and the aly guy is (8.5-6.0)*8.5 = 21.25 kg.

If we assume that 85 kg will do the job in all conditions then the carbon guy (of equal body length)needs to be at least 64 kg to right his boat and not 40 kg or something. In this crude mathematical theory that is as we have just totally ignored the weight of the stays + ails and the fact that water is clining to them. In fact the difference in reality will be less. Even more so when the sail is still curved and pulling the rig downwards because of the little wind that still flow across it. In fact the weight of the mast is not all the weight/force that needs to be lifted, it is only part of it.




The difference is not that much for sailing itself, it is indeed for righting. However I do agree that the F16 alu mast should be about 15 kg for the bare section. The only way to achieve that is to have a new die made. So if everybody will become a paying member of the F16 class then we may well buy a new die as a class and solve this issue.

Wouter

Thanks, that’s good information, but I was more thinking about issues like the fact that you have to weight for ex. min 80kgs if you want an alu mast, and that you will probably end up with a heavy boat.

Scarecrow,

Read the F16 class rules.

It only states you must be able to right the boat unaided. It doesn't specify the way in which you need to do it. As a matter of fact, things like shroud extenders can even make the alu mast rightable by sailor weight below 70 kg.

Wouter

My mast is of 2003

Wouter

The mast Valtteri was referring to is in fact the one of the Sydväst Blade and its 18 kgs tip weight 8.1 on a bathroom scale (they are often under the reality to pleas the one standing on it). So close to Valtteris as they are probably of the same making. So could somebody now for the transparency tell from when this die was used to make the mast and where did the old one go.

Everybody WAS supplied with correct information each time any info was asked. No-one can blame any other person for not supplying info when not asked for it. Also the fact that someone doesn't believe the info supplied doesn't mean that it is wrong or that it is part of protectionism.

The argument for the alu mast was and still is that that mast is the most cost effective way to a given level of performance. At all times it was agreed that it takes more body mass to right when using ONLY a righting line. And at all times it was suggested that this issue can easily be overcome by a righting bag or other aids like shroud extenders. If you are 75 kg then a small bag of 10 liters will easily do the job. Several F16 sailors are doing it this way. When there is some wind you won't even need the bag as with the correct technique the boat will come up with much lower body weights.


I'm truly sorry Gato, but it does really seem that a large portion of the way you view the situation is caused by the fact you look very negatively on the alu mast (incl. all weights and drawbacks you can find) and very favourably to carbon (ignoring all other factors in righting and limits in class rules).

The core of the situation is again the tip weights (yours was 8.0 ?, Val's 8.5 kg ?) The carbon mast tipweight is at least 6.00 kg as per F16 class rules, but these tipweights already exclude 5.0-6.0 in sail weights, 1.5 kg in standing rigging and easily a few kg in water sticking to the top of the rig after a capsize.

I have seen a 85 kg guy being unable to right his Stealth F16 with a carbon mast. We flipped almost simultaniously, I got mine up and he didn't. This is one indication of how important the other factors can be. They were enough to overpower a 2.0-2.5 kg tipweight difference.

While there is definately a difference in righting between alu and carbon it is very easy to over estimate or overvalue it. There are indeed other factors in play that can't be ignored.

Wouter

No records are kept on individual masts. As such I do not know from which batch you mast came from. The mast did come from Catamaran parts stock which may well be a portion of the VWM stock. Masts from these stocks are no older then 2004, although I know that VWM was included in more then 1 production run of masts so your mast can be well younger. In fact I expect your masts to be 2006 or younger.

I don't understand the last part of your question. I'm sorry.

Wouter

It was only referred to one mast option in the building instruction, but I hope when you are selling the same boat you are giving a choice. My hulls will anyway end up with planks nailed across serving as a platform to go into the water after the Sauna, and I am scared that you are about to insert the last nail in the coffin of the F16 class in Finland at least for the moment.

I think everybody would feel sad if somebody has sold you a 18kg tube to put on top of your boat, when you discover that you could have bought a carbon tube for the same price: 500£ What is cost effective in that for the buyer?

It is always somebody else his fault right ? Never your own !

You would maybe have a point if you were adviced to get alu while the persons doing the advising had carbon themselves. But as a matter of fact neither the designer of the Blade F16, the builders VWM, Australian Formula cats and AHPC nor I myself are sailing with anything other the alu.

Forgive us for advising something to you that we felt was good enough for ourselves !

I'm sorry to hear that you are unsatisfied with the Alu superwing mast, that you are unable to build down to minimum weight, that the Pixie and F12 are alot easier and quicker to construct. I'm sorry to hear that this will be end of F16 in Finland, but you really can't lay this on our doorstep. There is such a thing as your own responsibility in these matters. Hell, we also weren't there to tell you that you should have bought a Toyota instead of an Opel automobile.

I'm truly sorry Gato, I'm very happy with my 121.8 kg homebuild F16 with an alu mast and 8.3 kg tipweight. It is the right boat for me and I've never gone this fast on the water for an investment of 12.000 Euro's. If your threshold of satisfaction is so much higher then mine (or others like the Blade F16 designer) then I guess we just have a difference of opinion and the F16 class is not for you.

Wouter

The quotes I held at the time (even from Stealthmarine directly) were considerably higher then 500 pounds.

Wouter

There is nothing wrong with the hulls, it’s what’s “going around”. There is the first A cat coming to Finland so my thoughts are drifting in that direction...

So is it correct that there have been two different dies (I wasn't aware of that), or is that the part of the post you are saying you don't understand?

I've read the thread a couple of times, but I'm not sure I'm understanding your concern Gato. Can you clarify - is it that you feel that you won't be able to right the boat, or that your boat is not going to make minimum weight? Or that you bought a mast that doesn't have minimum tip weight? Or something else?

There are NO TWO DIFFERENT DIES of the superwing mast that I know off.

As far as I can tell there is only one; but while I'm often pretty up-to-date on these matters I can always be wrong.

I have been part of a project to design a new alu mast to replace the Superwing section but that project was put on hold before a new die was made. To my knowlegde this project has not been revived. Maybe that is the source of the rumour ?

Wouter

Well, was thinking to stop, but as you ask, one of the reason is that it’s very hard to get a straight answer to a simple question. Take as an example my question about the die, either the one who knows doesn’t want to answer or has not seen the question or is hiding the truth of some other reason, those who don’t know do better leaving the question unanswered. For me it’s clear, if you take a new die in use you check the result. And as the old die was giving tubes 14-15 kgs you expect something like that when buying no?

The A-cats are excellent boats. It is very understandable to have your thoughts drifting that way. If that class is suiting your mindset better then by all means go for it.

If you want to homebuild an A then I can assure you that the available building plans for A's are alot less complete and alot more dated then the F16 plans. Building a 75 kg timber A-cat to min weight will be alot more challenging then building a F16 down to weight.

But maybe we have another solution. Considering you feel so passionate about a carbon mast and having it replace the aluminium one then why not do exactly that ?

Order 2 carbon masts from Stealthmarine (after getting a definate price quote) and ship the alu masts back to catamaranparts where they are sold off as secondhand. Sure you'll loose some money in the proces, but building c.q. buying a complete new A-cat will cost lots more.

Or better still, sell your alu masts to the Norwegians and Swedes. There is a Swedish Taipan owner who bend his mast when his boat tipped over in a blow. You guys will meet in the spring time for a Scandinavia F16 regatta right ? Maybe the perfect opportunity for selling off your alu masts while getting some good return of investment. Then you can order the carbon masts and be happy again. I'm sure Rolf is interested in the mast, if not his friend who ordered a new F16 design but that still needs to be shipped to him. Removing the mast shipping costs may well be attractive to him.

It's an idea.

Wouter

I'm happy, just started to make the first half of the mast for the DS12.

If it's true that anyone is concealing information (and I have no knowledge that that's the case) I'm certain that the vast majority of us here are interested in openness and clarity. So can I ask what the source of the 14-15kg figure is? Wouter indicated earlier that as far as he knows there has only been one die. There seems to be some misunderstanding floating around somewhere. I'm sure we can get to the bottom of it.

The source of that is Phill, had a private discussion with him.

The boffins are working on the spar issue.........

Give them time..

Thanks. I guess he won't be online for at least some hours, but hopefully he can shed some light on the discussion.

How much would a die cost?

Just a quick reply for some points (I didn't have time to read this through properly).

1) There has to be two dies because our wall thickness is 1.85 mm and generally the thickness should be 1.6 mm (15.6 % more), also AFAIK Marcus posted that AUS Blade has 17 kg's total weight with standing rigging.
2) General message in this forum is that it's not that big difference which clearly isn't so. It's my fault that I didn't get quotes from another places and discussed weights before ordering but I trusted posts in this forum. I really don't think that we have enough data available (like T's post their mast measurement online) and people are not usually willing to talk about difficult matters.
3) Gato generalized too much with his formula but with university physics righting is basically two moments i.e. moment of the boat and skippers moment against it and if we have heavier mast the CG moves towards the top. Of course boats moment changes depending on it's angle, but still fact is that skipper has to have lot more weight if we slap few kg's to mast. If I have to have 10 kg's righting aid it's starting to be a problem and all this could have been done with let's say any other cat, whole F16 appeal to me was versatility.

I'll read this thread and write proper reply later when I get my kid to sleep in few hours.

I dont know anything about the superwhing that is not commonly known and have been posted on this forum. I do know that a die will wear out over time and that the later batches will have thicker walls. I would think that is the issue here? The superwings are made by Goodall and not the F16 class so we dont have complete control over them.
£500 for a bare carbon tube from JohnP?? Whow, that is a good price. Unless you really want a wingmast or an alu mast, that sounds like a really good option. I dont think there is other reasons for not pointing you in the direction of Stealth Marine and JohnP than simply not thinking about it or not knowing the price. After your posts about the issue, I am certain others who ask about mast tubes will be informed about both options. Dont help you much unfortunately. Unless you build another F16 (a DS-F16 would be very interesting. We need a hard chine design) and sell the Blade. Probably not a very attractive option for you at this time.

The largest difference I see between the A and the F16 is the spi. Personally, I dont want to go back to a non-spi boat in our dominantly ligth-wind area.

People are quoting prices from John P without actually asking him.

I do not think it is appropiate to quote prices that may not be correct.

John may or may not wish to post his proices on the forum. If you want a Carbon mast from John, you should call or email him and discuss it.

So you mean that the one originally posting this price was pooping from a hole a little bit higher than his a§§hole, seems to be a common thing here...

No, I mean that anyone quoting a price for an item which is not on the website of said supplier is peotentiall mis-representing the actual price.

I'd be very fecked off is someone said I would provide my web hosting and forum design cinsultancy for 100GBP per hour, as that is not the rate I would charge.

IF someone wants a Stealth Carbon mast, they should contact John and ask him what the price is.

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.



<out of line>
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.
</out of line>

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

<out of line & offtopic>
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.
</out of line & offtopic>

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.

would you cnc the female mold or cnc a male plug and pull a female mold?
If the first what would you consider to be the base cnc material?

Years ago I tried to do this but the foam manufacturers here couldn't make me a foam block big enough to form a skiff mold..

Stewart, everything goes to plan it will be straight to female moulds using a "tooling board" type product with or without a tooling paste. We're doing some test parts (F12 foil moulds) in a couple of weeks. The ability to machine 3D shapes is a bonus feature on the new router that my client has just aquired and we hope to use it to make moulds for composite cabin tops on his existing aluminium hull designs.

well I learn something every day!!

So why didn't you tell me about this 15 years ago!! Looks like for limited run one can even use it for prepreg!! Thanks really useful info..

Anyone want to build a skiff? I have a design ready to go! <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Nope, but if you have something to build an A cat the thing is different <img src="http://www.catsailor.com/forums/images/graemlins/crazy.gif" alt="" />

A cat? hmm.. Sorry no and Im not a good enough designer to give you one that would be more than a dog..

However I grew up building skiffs so well aware of the wedge hull platform.. A few pieces of ply at the start of winter and you had a skiff by the season opening.. Especially Cherubs were the kids winter projects around here.. This is where Murray and Bethwaite learnt their trade.. If it didnt perform there was always next winter!! It was an exciting time to grow up..


<img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />

Well, I am coming from mono hulls so maybe, but now we are off topic...

Also it would be interesting to know if that was the case with lighter mast because (harsh generalization) slapping over 2 kg's to mast requires more than 5 kg's of skipper weight. Let's keep in mind that righting might be ordered when there is no wind and thus skipper would violating rule 1.9.1 even though in normal windy conditions righting would succeed (I do believe in righting in all conditions because it makes boat safer).

Best solution would be that manufacturer measures them, somebody should be doing that quality control wise anyway. If that's not possible then data from every boat measured should be made available somehow. That way people could be making their decisions based on real data.

Wouter mentioned something about China... Hopefully somebody has not been that “stupid”...

for fear of throwing fuel on the flames.

Formula cat, Vector etc get what they are given by AHPC. I doubt they have any choice in the masts they receive. When Boyer was heavily involved the quality control seemed much higher.. Hopefully this will improve as the new factories get more experience.. As for where the masts now are extruded I am not 100% sure.. The only person who would know is Greg Goodall.. Whether he will tell is another issue.. Saying this his sails still seem to be showing the way and that division seems stable...

I do know that Chinese extruders are not guaranteeing a straight tube under 2 mm wall thickness.. This may be where your getting the chinese reference.. This basically leaves the vast majority of Chinese extruders unacceptable for us to use.. Saying this there may be a factory in China who has the technology & skill to do the job.. But finding the gem inside the box of dross isn't an easy task unless you willing to spend a few months in China and paying a trusted chinese associate to walk you through the process..


Guys I know his isn't satisfactory but please be calm.. There are two avenues of exploratory investigation happening to improve the situation.. One or both could come up trumps with something for the F16 population.. We just have to give the boffins time to work the numbers.. Remember these guys are doing the work for us for free.. Even if it goes ahead they will only just return their costs without labour costs.. So we cant place too much stress on them to finalise the research unless we pay...

My only suggestion is contact Stealth and get a current bare bones stick quote.. If your desperate for a stick asap and do not trust the recent superwing batches. Or contact Scarcrow and get plans for his ply/carbon wing.. <img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />
But if your a Viper "one design" owner I guess your stuck.. <img src="http://www.catsailor.com/forums/images/graemlins/crazy.gif" alt="" />


<img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />

The first ply/carbon wing for homebuilders designed by Scarecrow are under construction <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Valterri,




Well the simple reason is that this info (which is not yet determined to be true over the full range of masts) was not "general knowledge" till your story appeared. I for one did not know it.

I simply can not advice you or make general knowlegde something that I don't know myself. Also I have no indication that AHPC was aware of the variation themselves.

Again, your 2 masts are the most heavy supering masts I have ever encountered. Interestingly enough I have measurement data on a mast bought last year that is below 15 kg for the bare section. It is
almost certainly from the same batch as your mast. I remember that your first claims were that the bare mast weight was 19 kg's although you have already adjusted that down to 18 kg now ; incl downhaul and fitting ex spreaders.

I told you a million times already, the measured data I have on about 15+ mast does not conform well to your data. Now indeed I don't go over to the extrusion plant and measure all masts for compliance myself, sorry !

You are grasping at straws and starting unfounded rumours all over the place.

There are no 2 dies, we didn't know about the variation in your mast, our measurements of a subset of the complete batches do not comply well with your measurements, there is no indication AHPC knowns about this and we have not encountered this problem before. We have weighted slightly heavier masts but nowhere near to your measurements.

Now, I understand that you are unhappy with a mast that is several kg heavier then it is supposed to (and that other young masts are); I think you have a right to be. But you are trying to make it into a situation were you have been intentionally deceived by a group of people which is simply not the case.

Wouter

It is interesting to note where some of the cat builders are getting their beam and masts extrusion from.

Our Superwing mast however do not come from China.

Wouter

Several people in the F16 class know the details but are bound to some limitations set out in the agreement.

Wouter

They must have because I have two off cuts here, one from my mast and one from a sloop section and the cat section is physically smaller than the other, not just in wall thickness, if for example I cut the mast track off the cat section it would fit inside the main body of the sloop mast.

This could be the explanation, the flaw in the soup is that somes are still saying that the weights of the new spars correspond to the old cat spar and not the sloop spar if I understand the things right.
Do you have any idea of how big the difference is, maybe some Taipan guys have had the mast on the scales as they seems to be aware of the difference.

Matt,
That is not consistent with my understanding.

Are you sure that you are not comparing the masts
used by AHPC on the T4.9 and T5.7. because the T4.9
would fit inside the T5.7 mast if the track was cut off.
Also the original Aussie wing (extruded to avoid importing Sori wing mast from Italy for A class) would fit inside the T4.9 mast.
A quick measurement of the major and minor axis would
tell the story.

Regards,
Phill

The cat rigged mast section is 145mm x 59mm and what I thought or think is the sloop is 150mm x 62mm.

My apologies if I'm mistaken, but thats what I was lead believe the bigger section was - the sloop section.

Regards

Matt,
That is interesting.
I've not come across the 145x59 section before.
The other one is the standard section.
My understanding is the same as Wouter's in as much as there were some cat rigged sections but likewise I was of the understanding the only difference was wall thickness.
Unfortunately I have never actually measured one to confirm.

Regards,
Phill

I sent an email to AHPC about this, hopefully they'll have an answer.

And to Wouter I have to say that my error margin with bathroom scales is three times smaller that actual mast weight difference that came out wearing die (which is acceptable by you), ínternal DH and mast foot has always been included in both numbers (and said so). Also now that mast was re-measured it was totally dry, previously it could have easily have some ice attached here and there even though it looked not to be the case.

All I'm getting at that we have different masts here in Finland than rest of the guy's out there (15+ measurements) and you don't believe that it is the case and thus your are trying to question my reliability or you try to say that there is no difference. Why is that so, are you personally involved somehow to this whole issue?

Well, we have a difference in wall thickness here it should be around 1,6mm and we have two spars here (in fact three the damaged one is the same) at 1,85mm and there must be some more of those on the market, don’t know how many spars coming out of a batch.

Gday Phill

Saw the Blades at Portland. Very Nice.

I bought the section from Darren Peters in Adelaide, you may know of him, he advertised it as the original cat rig section and bought it as a spare, when he sailed Taipans, from my understanding he too built good hulls and was up near the top of the list, thats all the info I have.

When I bought the hound fitting from AHPC, it took me a while to reform it to my mast section.

Regards

Maybe but its Greg's decision what info is released on his business.. We must respect that... <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

If I understood the posts of phill and mattaipan right the profile of the AHPC Superwing is 150x62mm. Can somebody confirm that please?

I have not been reading this whole thread but why would you want to be able to right your boat in any condition? <img src="http://www.catsailor.com/forums/images/graemlins/confused.gif" alt="" />
IMHO if you go over in anything under 10-15kts maybe you should consider staying on the beach or something <img src="http://www.catsailor.com/forums/images/graemlins/blush.gif" alt="" />
And if you want 100% certainty that you can right in any conditions maybe you should have spent some more cash and bought the light carbon mast instead. <img src="http://www.catsailor.com/forums/images/graemlins/tongue.gif" alt="" />

From F16 class rules:

1.9 Minimum weight of the crew

1.9.1 There will be no other restrictions on crew weight apart from the requirement that the crew weight must be sufficient to right the boat unaided under all encountered sailing conditions.

So boat should be rightable in light/no wind or rules are violated intentionally (in my case).

Aren't you taking things a little to literally?
Just take one of these ultra light weight "righting devices" with you and you will be able to right in any condition:

No Valtteri,

The rules only stipulate that each F16 boat must be fitted with a righting system that allows the crew sailing the boat in a sanctioned F16 event to right it in all conditions unaided.

You are constantly refusing to look at the righting alternatives. Which are righting poles , righting bags, shroud extenders, Gary's solo right system and several other setups.

A righting bag is the most simple and cheap alternative that will work for very lightweight solo crews on the F16. That system alone has several different setups.

The use of the single righting line is only one way to right a boat. One that will actually work for your 75 kg for winds above what ? 10 knots. So you only need to use an alternative system like the bag for the times you flip the boat in light winds days ?

I think you have a point where the mast is heavier then it really should be, and we are working on that, but for the remainer, aren't you a little bit over critical ?

Wouter

I can although I measure 150 by 62.5 mm

I think AHPC quotes it as 150x63 mm

Wouter

Thanks, just don't want to mix the things up

I know that in the past there have been two different mast weights on the Taipan, although AHPC has been selling only the (heavier) Superwing mast for the last 10 years as far as I can determine. That is for both singlehander and double hander versions of the Taipan !

It is ONLY this Superwing mast that we have a F16 class usage agreement for. The lighter mast was never included in the deal for two reasons :

-1- At the time of F16 class creation this singlehander mast was not longer supported by AHPC itself. They had no stock of them and no intention of reproducing them.

-2- The lighter 1-up mast for the Taipan looked already to weak on paper to take the F16 rig with the spinnaker. At the time we were even a little uneasy about the Taipan standard (sloop rigged)mast holding up.


The lighter Taipan 1-up must was never seriously considered for the F16's and I have really no dependable data on it. As a result I can not have mixed up these two weights as I don't know the Taipan 1-up mast weight to begin with.

Wouter

Gato,

There seems to be some movement on this front.

I for one am really hoping that we can somehow organise a new alu F16 mast design that is down to specs. Because every analysis is showing that 14.5 kg for the BARE tube is really possible. Even it is redesigned to have a little more stiffness side to side.

Thus making the bare alu tube only 4.0 kg heavier then the F16 compliant bare carbon tube. As the older Superwing masts for sloop boats indeed were.

Lets keep our fingers crossed everybody !

Wouter

P.S. Everybody is noticing the "BARE" qualifier in the statements made above ?

Fully rigged masts will come out at higher weights although the difference between alu and carbon won't change as the same fitting are used on both masts !

Gato, Valteri, etc.

Please contact the builders and suppliers for information as all will be more than happy to discuss history, options, prices or whatever else you may want to know.
Forums are great places for misinformation (given with the best intentions usually though)

A die will vary with age, but there has been nowhere near enough masts built out of the AHPC dies for this to happen. Extrusions will however, very from lot to lot. The current extruder of these sections was choosen due to their relatively tight QC. The last batch of mast we recieved was just slightly lighter than the previous batches, but still within the QC range specified. Bends can vary also due to variences in the material properties, but this is much less likely. Note: carbon can also vary significantly. Non-spec materials are cheaper but we have gotten in some batches of material with significant variances in the areal weight. Process variances can also change the weight of each piece.

I am 68 kg and can right my boat by myself with out any aids in about 10knots or more of wind. I try not to go over in less, but carry a small trash bag just in case.

Note the Tornados have some acess to their boat statistics. These are from the class submitted measurers certificates. Keep in mind that these are extremely expensive platforms that the owners then have to pay to get certified. As we get certs on boats these could get published through the class but right now this information does not exist in a reliable format, so please be patient.

I don’t know exactly what to think, just had a phone call from Valtteri and it seems we have a spar with a profile of 145x61 with a wall thickness of 1,85mm. what spar is that? If the answer is “just a teardrop away” (Shrek II) for somebody please give the answer.

I can't identify it. Not a section that I recognize.



Some additional info on my mast (2003)

I took cut-off I have of my own mast (2003) and that of another (halveway 1990's and now partly my mainbeam) to digital scales at the food section of my supermarket, these are annually calibrated by the national authority. The cut-offs are about a meter long so it is decent measurement. And I took the average of the readout on different scales.



Results after multiplying to full length :

My mast (2003) = 14.332 kg / 8.5 mtr
Used older mast (halveway 1990's) = 14.930 kg / 8.5 mtr.

Accuracy should be within a 100 grams amplitude around this average (< 1.5%)

On average the weight 1.721 grams/mtr = 14.631 kg / 8.5 mtr and that is consistant with other mast measurements that were send to me over time with the exception of course of the masts currently in Finland.

My mathematical model of the mast (developped in 2002) gives 14.229 kg/mtr = 1.674 kg/mtr. and is therefor consistant (meaning < 5% offset) with the cut-offs that I have at home.

Of course these measurements are for the bare mast tube sections, no fittings whatsoever.

Wouter

Gato posted those measurements based on the damaged mast the other two that we have here are 150x63, they all seem to have 1.85 wall thickness though. The damaged section also seems to weight more but it has not been on totally dry conditions so I can't say if that is caused by it.

okay,

Lets echo this info to "the background" for a while and see what comes up.

Wouter

It’s quiet. If we considered your weights Wouter I have the feeling that the final spar would be something around 18kg. There is a lot of SS details on the mast and they are heavy. It’s stupid that the damaged mast seems to be of a different profile; otherwise it would have been easy to strip it and put it on the scale. I could do it with the Sydväst mast but for the moment I don’t find it necessary. Still it would be interesting to know what profile the damaged one is and why two different profiles on two spars shipped together.

Yes of course. I have all these things in excel sheets somewhere but from the top of my head a typical lean fitting out of the mast adds between 2.5 and 3.0 kg in total and adds about 0.8 kg to the tipweight. Of course this does dependent on the fittings chosen and also very much on the density of the foam blocks to seal the mast. A set of carbon spreaders arms is just significantly lighter then a set of proctor spreader arms. Fittings do include items like halyards and blocks.

I think a mast fully fitted but without side-stays and forestay should be around 18 kg when it is fitted out in a lean manner.

I seem to remember that the Tornado full carbon mast was 15 kg when fully rigged and that mast is only 0.5 mtr taller.

A compliant F16 carbon mast will be just under 14 kg.

Again, the differences in weight between carbon and alu only come from the bare tubes as all the fittings are pretty much identical. That is the reason why we are looking at bare tube weights and not full mast weights (except tipweight as those are implicetly fully fitted mast measurements)

What are fully fitted A-cat carbon masts these days ? Around 10 kg ?

The old alu A-cats masts were slightly lighter then the superwing alu, but not by much. Actually there are some A-cat alu mast designs that were actually heavier then the superwing.

Formula 18 masts are on 3.5 kg to 4.5 kg heavier then the F16 alu sticks so on average 22 kg when fully fitted. These masts are only 0.5 mtr longer and carry only 13% more sail area.

I seem to remember the old Alu Tornado masts to be heavier still (then the F18's), somewhere around 24 kg. Rolf will know that info from his head. I have it archieved somewhere but no time to dig for it.

Masts without diamond wires like the Hobie 16 are typically noticeably heavier then the masts with diamond wires. They need thicker walls to withstand the bending loads. This is why small boats like the Hobie 16 and Prindle 16 (but not nacra 500) are more difficult to right singlehandedly then you would initially expect even when their masts are shorter and their rigs are smaller.


Now you've got the full picture.




That is something that interests me as well, if such a thing occured. It is however outside of my sphere of influence. You will have to contact your supplier directly for that.

Could it be that he mistakenly grapped an old alu A-cat mast ? I mean the difference between a 150x63x1.6 and 145x61x1.85 mast is not easy to spot when not laying a tape measurer over the section.


Wouter

We have a much clearer picture after Valtteri has been spending his night digging. There are still some questions that remain unclear, among them the wall thickness. But be patient, we strip the spar, cut it to small pieces and x-ray it if necessary. Guess there will be some news before tonight, but we are walking shaky ground now.
Btw. not easy to spot but when you put the fittings from another spar...

I asked Hans to post here and clear out the different profile issue.

I think that we need to strip those masts to find out for sure what they weight, I'll do that to my mast next weekend and hopefully Gato will find time to do so to their mast. I'll also use different micrometer to re-measure the wall thickness, at least what AHPC has in stock doesn't match to that. So more data coming in during weekend.

That is a good point ! Hadn't thought of that.

Wouter

Be sure to vile a small bevil (ramp) to the edge of the mast section. The vernier measurer (micro measurer) will maeasure the wallthickness some 10 mm away from the edge anyway. The saw cut itself (shards) can easily add a few tens of mm wallthickness and 0.15 mm difference is well inside that range. I had that problem just yesterday when keeping apart a tube with 2 mm wall and a tube with 2.5 mm wall for my landyacht mast. I didn't think the shards would pose a problem with (a large) 0.5 mm difference in wallthickness but I must admit that I was wrong.

Wouter

I’ll find the time, we are getting 24 new fresh hours each day after midnight. Don’t worry Wouter, we are using micrometers of good quality and we will not do it alone, too much work to strip and put back the things again.

The person who has the answer will not come forth and give it. A lesson already learnt is always ask for the specs when ordering, check that they are the right ones and verify what you get. As Wouter said, it’s very difficult to see the difference between the two profiles and a mistake can be done by accident or by somebody sitting on a pile of useless spars good for nothing and are tempted to pass one on from time to time...

I stripped down all fittings out of the mast and bare section weights 15.6 kg's, I believe that Gato's mast weights 15.5 kg's because we had 100 gram difference while fitted. I talked with AHPC and they said that typically mast section weights 15 kg's so basically we are quite close to that number well within manufacturing process variation, even though masts shipped to Finland seems to be on the heavy side.

If typical mast weights around 15 kg's then I don't think that I'll have too hard time righting (with aid) but I do see the difference quite large to carbon one (typically over 5 kg's), maybe with hand picking you could get better section but for shipping abroad that is obviously not an option. Also we got shipped one mast that is totally different profile (I was told that it was taken from wrong pile by accident), so obviously I'm not totally happy about all this. Happier than after weighting the damaged section though.

Hopefully one day we have enough real measurements available somewhere so that people can read that instead of hear say on open forum (let's face it even this post is such <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />).

If there is interest, I can help out creating an online database on this and other measurements next winter. Measurers would submit the alread quality controlled data and we could keep measurement certificates online. Perhaps an idea?

NB: Next winter!

This mast was broken in a land accident.

It was a (I was told) light weight single handed AHPC section.

I never thought twice about it. I used it in all conditions, single handed and two up.

I never used a spinnaker with it, but did use a hooter a fait bit.

This section is 5.15 mts(515 cm) it weighs 8.5 kgs.
My vernias are not the best, but the wall thickness is more than 1.5 mm and less than 2 mm. Most likley 1.8 mm.


You do you sums.

My calcs suggest that would be around 14.2kgs for a 8.6m mast section.

Similar to wouters calc on the 150 x 63 section.

Are you the mast is the lighter Tiapan section.?

That's right in the range of what we have been getting. The history being spread around here, is that the 2 sections are the same with the exception of the added riblets to increase stiffness. From a cost point that makes the most sense as well.

I'm again somewhat confused, are you getting 14 kg's section with riblets or without?

With. I do not have a copy of the QC sheet from the last batch, but this right about what all of the ones we have recieved haved weighed. I beleive this is near the low end of the range, but the acceptable range was not very wide.

Ah well, then there is again bigger difference to what we have. I guess that yours are not hand picked either because you are ordering those in batches.