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Re: Why does Macca hate F16s? [Re: pepin] #205917
03/17/10 11:28 AM
03/17/10 11:28 AM
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pgp Offline
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+2 for Wout! You da man!


Pete Pollard
Blade 702

'When you have a lot of things to do, it's best to get your nap out of the way first.

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Re: Why does Macca hate F16s? [Re: pgp] #205921
03/17/10 11:52 AM
03/17/10 11:52 AM
Joined: Feb 2005
Posts: 1,382
Essex, UK
Jalani Offline
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Now, don't you feel much better by putting forwrd a reasoned argument with no attacks on any one individual? Of course, it's an argument that you have placed on this forum before and events over the last several years have proved the concept that the founding group envisaged - for that you must all be strongly congratulated. It is sad though that you should have to be repeating yourself ad nauseam to the 'non-believers'.
Thanks for taking the trouble to put fingers to keys for this thread!
+1


John Alani
___________
Stealth F16s GBR527 and GBR538
Re: Why does Macca hate F16s? [Re: Jalani] #205929
03/17/10 12:46 PM
03/17/10 12:46 PM
Joined: Mar 2006
Posts: 1,246
Orlando, FL
tback Offline
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I can now "weigh-in" as a reasoned argument has been stated.

+1,000


USA 777
Re: Why does Macca hate F16s? [Re: Wouter] #205935
03/17/10 01:47 PM
03/17/10 01:47 PM
Joined: Nov 2006
Posts: 120
Finland
valtteri Offline
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Finland
Originally Posted by Wouter

macca, don't guess but measure !

Alu tip weight superwing is 7.8 to 8.2 kg (depending on fitting out like heavy spreader arms etc)
Carbon F16 mast tipweight (per rule) 6.0 kg

Wouter


I have weighted one AHPC superwing tip weight to be over 10 kg's, fully fitted by Catamaranparts. After that broke last summer I bought a T carbon mast, cut it to 8.5 m length and measured 6 kg's tip weight. Over all weight saving of fully fitted mast was 7.8 kg's. Of course I admit that my superwing was fatter than what you measured, but I also guess that since T mast is designed for bigger loads the F16 optimized mast would weight less, any Stealth owner willing to give some numbers? Also the other superwing mast weighted in Finland was only 300 g lighter than my mast, so that wasn't some random case.

Btw, before someone notices, that mast makes my boat not to be F16 compliant anymore since mast base is over 7.5 cm's from beam braking the box rule 1.4.1, so this might make me not worthy of responding here wink.

Valtteri


Valtteri Blade F16
Re: Why does Macca hate F16s? [Re: valtteri] #205945
03/17/10 02:32 PM
03/17/10 02:32 PM
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Wouter Offline
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Quote

I have weighted one AHPC superwing tip weight to be over 10 kg's, ...



Valtteri,

This is one reason why I don't believe that you were shipped a superwing mast; or at least not one that came from the AHPC extrusion die (maybe it is a copy by another builder ?).

To this day I don't feel right about the situation with regard to the Finnish fleet, I think it was handled very badly, but sadly solving it is outside of my sphere of influence.

I can give you Stealth owner numbers. Their (newer) carbon masts can have tipweights as low as 5.5 kg and therefore have to carry tipweights for official racing. This was indeed done during the GC2007 event.

The 6.0 kg tipweight rule was discussed with some carbon mast builders and they felt it was a good measure to produce a commericially attractive robust mast that would stand up to abuse without being overweight. They said less was possible, but not really necessary.

Overall, this value has proven to be a good compromise.

I also know the superwing masts fitout has been further developped (for example higher hound fitting) and is now better suited to the F16's in the way of flexing. This development was accompanied by further sail development. I feel that if you take a modern superwing rig (like the AHPC Viper) and one of the first F16 rigs (like the Taipan F16's or early Blades) that you will notice some difference as well. The mast/sail combo's have been better tuned to F16 sailing now. I for one will never underestimate the alu superwing mast + sail combo. It is one of the best setups.

But that is of no interest to you Valtteri, however I'm very happy that you have found a suitable replacement (and feel it is a real pitty you had to correct the situation on your own). Personally, I couldn't care less about your mast base height (unless it is 0.50 mtr tall !) and I for one will never protest you on it. Neither will I ever be childish and consider you anything but worthy to comment on this forum or anything other related to F16's.

I stand by the inclusiveness clause that the F16 class was founded upon. That means including Macca, you and also persons like myself. I know several others (if not many) members of this class feel the same way.

So I say come join the fun and ignore the water lawers !

We are not racing for sheepstations as the Aussies say !

Regards,

Wouter


Last edited by Wouter; 03/17/10 02:34 PM.

Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Why does Macca hate F16s? [Re: macca] #205957
03/17/10 05:35 PM
03/17/10 05:35 PM
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Wouter Offline
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Macca,

Quote

If the Carbon mast is no quicker, why allow it??



If the carbon mast is no quicker, why DISallow it ?

Are we really claiming here that the customers don't know what is going on.

We don't allow diamond inlays in the hulls either; if someone wants to spend money on that then why prevent it ? The F16 class rules are engineered to allow for fair racing between boats of different makes while allowing maximal personal freedom, not to prevent some person from wasting money on unnecessary things.

Isn't it time we start treating catamaran buyers like capable adults, you know, WITH a brain of their own ?

Wouter


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Why does Macca hate F16s? [Re: Wouter] #205960
03/17/10 06:01 PM
03/17/10 06:01 PM
Joined: Jun 2001
Posts: 9,582
North-West Europe
Wouter Offline
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But I will say this for Macca.

I'm not in the slightest afraid of him or what effects his postings may have on the class. In fact, I feel his contributions are valuable (as long as he posts accurate data). Afterall, it is actually the wolfpack that keeps the heards of grazers healthy by picking off the weak and the sick. Thus keeping the herd strong and more able to fend off any further attacks

I'm also not scared about any "bad image" the class may get from these discussions. In fact, I believe the class will look better when such discussions are handled well. It is also a way to show that the class is stable and confident in her product. It is also a way to show potential customers that these issues have been considered in the class and why the class feels that they have been addressed adequately.

Sure, the process is repeatitive but so is the process of attracting new class members/customers. Many new enthousiasts will not read any postings from 18 months ago. Anybody not willing to explain the class stances repeatedly is not fit for the role of promotor !

I feel it is very wise to get into a discussion with Macca on this forum and explain the case from the perspective of the class and thus convince potential new members of the viability of the class or indeed inform them properly of all issues before they pull the lever on 15.000 bucks. We must not be afraid to loose a few customers if indeed they are looking more for a strickt OD class then a formula class. I rather have them change their mind before they buy then afterwards as the latter is arguably worse promo in the end.

Being secret or ignoring issues that are being raised is actually the worse approach that anyone (or any class) can take. Often this creates the feeling that there is some truth to the accusations. Afterall, if there wasn't then why would the issue be ignored or made secret ? This is negative spiral that should be avoided at all times.

This is also why I strongly believe that both class members and non-members have equal rights on forums like this. Both can bring excellent new points to the table and no class has ever been grown by preaching to the choir.

Therefore I say, lets keep Macca on board and engage him on those points that we see differently or that are verifiably inaccurate. In the end, the interested parties (who are not class members), will respect us for it and most likely consider us more seriously as their next hobby.

With regards to Macca personally, I think he is a very skilled sailor and passionate about sailing catamarans. I also think he reasons from a different viewpoint then us (or the F16 class) and that is where most of the disagreements come from. Doesn't mean that he is dishonest or wrong or that we are; We just disagree. However none of this is important as the world is full of people who think differently about things and there are more then enough people of each opinion to support either stance (class).

In concrete terms. There are enough people interested in an arms race to support and grow the A-cat class. There are enough people who feel that only identical boats can be raced fairly to support the Hobie 16 class. By the same reasoning there are also enough people to support the F18 class and indeed the F16 class in the way these are setup now. That is where Macca and I disagree personally. I see the F16 class as the class for sailors who are more into recreational racing or versatility (=parents) and don't worry much about a carbon this or aluminium that. For truly serious hard core racers we have the F18 class with its tighter controls or the A-cat class for the truly hardcore tinkers (arms racers). The F16 class, as currently setup, is best as a feeder class to either. We take in the enthousiasts that want to make the next step in catamaran sailing and racing (up from whatever old secondhander they bought a few years before) and send off all those crews to the F18's and A-cats that have been infected by the racing virus or development virus and are looking for the pinnacle in that way of enjoying a sport.

This role will suit the F16's very well and provide for enough turn-over to support and grow this class; irrespectively whether the boat sailed has an aluminium or carbon mast.

With kind regards,

Wouter


Last edited by Wouter; 03/17/10 06:10 PM.

Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Why does Macca hate F16s? [Re: Wouter] #205982
03/17/10 10:47 PM
03/17/10 10:47 PM
Joined: Dec 2005
Posts: 1,121
Eastern NC, USA
T
tshan Offline OP
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Eastern NC, USA
Yo. Sorry for not chiming in since starting this shitfan, but I wanted to see how this played out. Here is what I got out of the thread (I have a bad case of ADD ro ADDHD or whatever):

1. Macca likes F16
2. Macca is worried the F16 will eat its own and a class killer is coming out, by someone with more money than sense
3. Macca bases this on that the Viper is the best F16 and the Viper is a little obese per class rules

My field work says:

1. Macca is right to like F16
2. Macca is right to like the Viper as a F16 in today's environment
3. Macca is right to applaud AHPC support worldwide

BUT, I think the F16 community likes the idea of lighter boats and I personally do not think Viper's are inherently faster than any other F16 design across all conditions.

The reason the Vipers are doing well are two fold: sail plan and sailors.

First, the Viper sail plan is awesome (Goodall will tell you the sail plan is 80% of the battle, hull shape comes next). They have done their home work and their sails are very nice - especially against first and second generation F16 sail shapes).

Second, at all (US based) big regattas Vipers have been sailed by sailors of well reknown (Goodall, Casey, Daniels) - of course they are going to win. It is the sailor, not the nut that wins the races.

The Viper is the flavor of the day for F16 - but other new designs are going to challenge them (Rapter, Falcon, etc.) - especially when sails get dialed in....

Just ask the Vipers abt the Blade that beat them by over an hour at RTI this past year (Blade + Goodall sails). I've seen all F16s excel depending on the saillors on board.

It still seems to be the sailors that make the difference. I have owned a 1st generation Blade and a 2009 Viper. My Viper was faster than my Blade, in my mind wholely attributed to sail shape and foil design (my Blade had the old school low aspect boards).

I do not think the 135kg F16 is the future ...


Tom
Re: Why does Macca hate F16s? [Re: tshan] #205983
03/17/10 10:53 PM
03/17/10 10:53 PM
Joined: Dec 2005
Posts: 1,121
Eastern NC, USA
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tshan Offline OP
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Btw, Macca - I appreciate your candor on the class and I hope your foreshadowing doesn't become the reality.

I'll be rooting for you on the F18/V40/AC circuit. If you need crew - just call!

t


Tom
Re: Why does Macca hate F16s? [Re: tshan] #205987
03/18/10 12:31 AM
03/18/10 12:31 AM
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I find it hard to commit a huge amount of cash to buying the leading design when it is nearly 30kg over the minimum and can be easily superceded by a replica made at min weight. It is a big risk when you go to resell the boats. For a Formula or a Box rule class you expect evolutionary steps that have incremental advances. Slightly better sail shape on the 2010 version compared to the 2009 version for example, rather than "revolutionary" changes that you can hardly replicate on your now "out-dated" design. This is the big risk in the class at the moment that I see.

But as a sidenote I do sail a development class, ie moth, which has these risks. No min weight, only 6 rules to talk of, fully open development. I chose this risk and was fully aware of this before making this decision and everyone in the class is aware of these risks. But I don't see a formula class having these risks in the concept of the rules.

Re: Why does Macca hate F16s? [Re: Wouter] #205989
03/18/10 02:58 AM
03/18/10 02:58 AM
Joined: Aug 2005
Posts: 221
Netherlands
Hans_Ned_111 Offline
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Valterri was supplied one superwing (AHPC) mast and by mistake a wrong section but close to the superwing section.
A rigged superwing section without the standing rigging but for the rest everything attached is close to 10kg tipweight, a bare section can have around 6 kg tipweight

Re: Why does Macca hate F16s? [Re: Hans_Ned_111] #205994
03/18/10 04:15 AM
03/18/10 04:15 AM
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North-West Europe
Wouter Offline
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Quote

Valterri was supplied one superwing (AHPC) mast and by mistake a wrong section but close to the superwing section.

A rigged superwing section without the standing rigging but for the rest everything attached is close to 10kg tipweight, a bare section can have around 6 kg tipweight



I would like to add the following data to the public record.

My own AHPC superwing mast was shipped from Australia (AHPC stock) and was measured (fully fitted after 3 years of use) by the class Chief measurer to be 8.9 kg WITH THE SIDESTAYS AND FORESTAY still attached. These were/are 4 mm thick stainless steel 1x19 wires and weight 1.7 kg together. Therefore these add (0.5*6.0/8.5)*1.7 = 0.6 kg to the tipweight measurement.

As a result my superwing mast has a tipweight of 8.3 kg (although my measurement form says 7.9 kg) and I'm using the heavy (suited to all boats) proctor spreader arms and heavy 1x19 diamond wires (not the lighter diaform wires as is typical on Taipans and newer F16's). I'm also NOT using the lighter T-terminals on my mast but the heavier plates and forks combinations. Basically, due to concerns of costs and robustness (I have the prototype F16) I have a fully sealed and heavy F16 mast. For example the diamond wires end plates are of the Nacra F18 design and I have also turnbuckles in both my diamond wires (not a single turn buckle or even the lighter threaded terminal plus nuts setup). I also have foam seals inside my mast above the internal downhaul system.

The boat by Frank (Vectorworks Blade) was weighted together with my own and his tipweight was measured at 7.8 kg if my memory serves me well. My mast is from 2000 and Franks from 2005. I do believe that the last mast is from another batch altogether as I know AHPC (and VWM etc) have ordered a new batch in the mean time.

These measurements I witnessed myself and I would not consider either of these to be close to 10 kg tipweight. I remember you being present too. I have received tipweight measurements by other owners and their data confirms the situation described above. The only exception here are the masts shipped to Valtteri.

Hans, if indeed your statements are correct then I'm simply claiming here that the data I hold all appear to be significantly lower then the claim that "a fully fitted F16 superwing mast is close to 10 kg in tipweight". Nothing more, nothing less.

I just wish to add the above data to the public record as proof that low tipweights with the alu superwing masts are indeed possible; even when build up using standard inexpensive components (I couldn't get the right diaform wires or lightweight spreaders) by an amateur like myself.


With kind regards,

Wouter


Last edited by Wouter; 03/18/10 04:30 AM.

Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Why does Macca hate F16s? [Re: Wouter] #205996
03/18/10 05:37 AM
03/18/10 05:37 AM
Joined: Aug 2005
Posts: 221
Netherlands
Hans_Ned_111 Offline
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Wouter,
Can you then explain to me according the photo´s attached how it is possible to have a standard fitted out alloy mast with the ( AHPC ) superwing section is already 8.0 kg and there is not yet attached the complete spinaker halyard ( incl the blocks )and the diamond arms and i am not talking about the standing rigging, which is normally not taken in the calculation.

This just done 10 minutes ago

Hans

Attached Files
Dscf0290.jpg (411 downloads)
Dscf0291.jpg (417 downloads)
Last edited by Hans_Ned_111; 03/18/10 05:38 AM. Reason: adding text
Re: Why does Macca hate F16s? [Re: Jalani] #206000
03/18/10 07:03 AM
03/18/10 07:03 AM
Joined: Jul 2007
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F
F18arg Offline
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As good neutral source I can tell you that these discussions (I think I´ve read fully all threads regarding F16 weight) are just the best promotion the class can have (after removing all personal attacks).
Macca is giving his Pro sailor view on the class, so don´t feel attacked, he always promote interesting discussions that benefit your class.

Too many times I just don´t sail and miss perfect conditions because of the hassle to rig and launch my F18 through the ramp on my own when no crew is available.
So a peformance light boat like the F16 is for sure an appeal for many Worldwide.

For sure you have Macca´s described risks in the future and you should take account on those.
But the intention of this class in my view right now is not becoming more popular than the all mighty F18, you just want a light boat to sail and with the creation of a class/rules provide a platform to race.

Keep up the good work.
Cheers,
Martin

lets join forces and get this sorted out [Re: Hans_Ned_111] #206017
03/18/10 10:35 AM
03/18/10 10:35 AM
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Wouter Offline
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Hans (and all other interested parties),

For some reason your attachment won't show itself on my PC. I also seem unable to grap it. If anybody can then please send a copy to me using my mail account wouterhijink(at)hotmail.com

I'm sure that the attached picture shows a scale with a mast tip layed on it. Most likely the scale is pointing to some high value and as such is intended to proof your case. I accept that much.

What I don't really understand is your question. I mean how can I explain something from just such a picture; for all I know you may have used some other mast or are using an alu top fitting to seal the mast (just as with Hobies / Prindles back in the day). In short it is impossible for me to explain something that I'm not part off or haven't investigated myself.

Having said this; the weighting of my own alu F16 mast and that of Frank was done in the presence of Frank, Pieter Saarberg (chief F16 measurer), you (class chairman) and myself. We have all seen my mast and can confirm that everything needed for sailing, including the sidestays, forestays, halyard and any thing else, were still attached. By that time I had been using that mast for three years and had just picked the boat (and franks) of the beach an hour before. Later that day I just connected the stays to the hulls and raised the mast. Spi halyard systems etc all went down and up with it.

We all know the scales showed a tipweight of 8.9 kg. Later Pieter noticed that the stayes were still attached and deducted 1 kg from that number and wrote down 7.9 kg on my measurement form. Franks mast was weighted without the side- and forestays and was (from memory) found to be lighter then my mast (7.8 kg).

Therefore I put my own mast and its certified tip measurement, performed in front of 4 witnesses, against your foto "of 10 minutes ago" (same with regard to Franks mast).


Now I would love to find out why the "old" masts are coming in so much lighter. If anything we can correct the situation to all our advantage when we know the cause. Afterall, my mast (and that of others like Frank and indeed Phill) show that a 8 kg tip weight alu F16 mast is possible and strong enough to survive regular F16 sailing.

It will be smart to try to reproduce the "old" masts.

Maybe the dies have worn out; that is a 1000 bucks fix (making a new die)

Maybe new dies have been made but the guy doing the milling made an error and set the machine to 1.8 mm wallthickness instead of 1.6 mm (that will add 1.9 kg to the bare mast section).

Maybe the company doing the extrusions has changed the extrusion speeds without notifying us, thus resulting in more expansion of the crossection then was intended when the die was made ?

There are a number of reasons why things may have gone wrong, but we know that truly lightweight F16 alu masts are possible as several of us actually have them. Either that or Pieters scales are totally undependable.

I say lets get to the bottom of this and try to sort this out.

I know we're are not on the best of terms recently, but you will find me a willing ally in this respect.

Wouter

Last edited by Wouter; 03/18/10 10:51 AM.

Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: lets join forces and get this sorted out [Re: Wouter] #206023
03/18/10 11:03 AM
03/18/10 11:03 AM
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Western Australia
Stewart Offline
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photos sent

Re: lets join forces and get this sorted out [Re: Wouter] #206025
03/18/10 11:14 AM
03/18/10 11:14 AM
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Wouter Offline
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Thank you stewart for sending me the pics.

Hans, your mast isn't so far off the mark is it ?

I see it is fully fitted out with exception of the spi-halyard (4 mm dyneema 15 mtr long section along the mast = 180 grams), (heavy) spreaders ( <1.5 kg ?) and the diamond wires (3 mm dieform together 12 mtr long = 650 grams).

These items add to the tip weight by the following amounts

Spi halyard (7.5/2 * 1/8.5) * 0.180 kg = 0.080 kg
Spreaders (3.0 / 8.5 ) * <1.5 = <0.530 kg
Diamond wires (3.0/8.5 ) * 0.650 = 0.230 kg

total add <0.84 kg to your measured tipweight of 8.0 kg making it overall <8.84 kg

Still more then my own mast but not too bad.

Valtteri was reporting tipweights beyond 10 kg.

Opting for lightweight carbon spreaders (like Phill has done) will shave off 0.350 kg from the tipweight and thus end up at 8.5 kg tipweight. I can envision that the added 0,9 kg relative to my own fitted mast is caused by the die widening (going from 1.6 mm wallthickness to 1.7 mm). Also note that my own mast section is heavier then Phills which is even older then mine.

If the same original die is still used then a couple of hundred masts have been made by it already. VWM/Falcon have used about 80 of them and AHPC about 400 (325 Taipans mast+ 80 Vipers); smaller batches went to Dynautic and Formula catamarans (Aussie Blade) and some 15% is disguarded or used as beams because they are not straight. I can easily believe that over 600 Superwing masts have been made over the years. Maybe that can account for 0.1 mm wear on the die ? (0.1 mm is the same as the thickness of a regular 80 grams A4 sheet of paper.)

Wouter

Last edited by Wouter; 03/18/10 03:02 PM.

Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: lets join forces and get this sorted out [Re: Wouter] #206030
03/18/10 11:29 AM
03/18/10 11:29 AM
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Ohh Hans,

I'm sure hope that you didn't include that metal tube visible underneath the tip of the mast into tip weight measurement !

Wouter


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: lets join forces and get this sorted out [Re: Wouter] #206046
03/18/10 01:31 PM
03/18/10 01:31 PM
Joined: Nov 2006
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Finland
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Finland
Hans's figures are correct and in line what I've heard from various sources. Adding diamond wires etc to measure fully fitted mast and accept the fact that there is for example +/-1 kg difference between tubes from the baseline then you might get tip weights around 10 kg's with heavy section like in my case. I'm not sure how much pitching this addtional weight would cause but at least if you need to turn the mast pointing to the sky the difference is quite huge at least for uni sailors.

I believe there is no reason to save weight in hulls since just putting carbon mast to most of the current platforms would mean that they need to carry some additional weight. All this has nothing to do with the topic, so sorry for hijack wink.


Valtteri Blade F16
Re: lets join forces and get this sorted out [Re: valtteri] #206052
03/18/10 02:36 PM
03/18/10 02:36 PM
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Wouter Offline
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I find it hard to accept the situation where superwing mast tipweights can range from 7.8 kg to over 10 kg (your claim Valtteri) when fully fitted. That would imply that one particular ready to sail superwing mast may be just short of 5 kg heavier then another with all of them coming from the same die.

That is a huge variation in extrusion weights (30%).

The default weight of a 8.575 mtr long F16 superwing is theoretically 14.5 kg. Even with a 10% up or down variation in crossections the range of tipweights should be running from 7.4 kg to 8.8 kg with its center at 8.1 kg.

My mast at 8.3 kg, Hans's mast at 8.8 kg and Frank's mast at 7.8 kg are all in that range. Yours at 10+ kg is well out of the range.

But I think the best lesson here is to check the masts before shipping them out. Even if that particular superwing mast was so heavy that it had to result in a 10+kg tipweight then that section should have been scrapped and replaced by a lighter one. This is no great expense. Afterall, the variations are random and therefore all weights from light to heavy will be in a single batch.

I'm not allowed to disclose the costs per mast but rest assured that 33% of a batch can easily be disguarded without significant cost increases per mast. An expense that I'm sure we are all more then willing to pay for a (worse case) 1.5 kg tipweight reduction.

Therefore any F16 builder will be smart to measure all masts and simply scrap the heavy 33% of a given batch. There is no need to use the heavy outliers.

This should result in tip weights below 8.6 kg when fully rigged. Even less when using lightweight spreader arms instead of the (heavy) proctor arms.

Wouter

Last edited by Wouter; 03/18/10 02:53 PM.

Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
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