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  #106  
Old 04-09-2012, 01:39 AM
CT 249 CT 249 is offline
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Originally Posted by Petros View Post
interesting idea, but I am not sure why it has to pivot. Wouldn't a beam with some dihedral (like wings) accomplish the same thing? Well I guess it would put the crew up a bit higher, but the lee side would clear the surface just as well. I tend not to like things that move or pivot if they do not have to, sooner or later it will give you trouble (typically at the most inopportune moment).

That is exactly the kind of simple ideas that the class I am proposing would be ideal to test out with an inexpensive boat. Any other class that would allow such experimentation would also require some pretty costly little boats (both hull and sails/rigging) to know if it will have any advantage.

Once we get the rules finalized here, you can take a copy to your local boat building school or foundation and see if you can get a chapter started there.
Pivoting wings are an old idea, abandoned in 18 Foot Skiffs about 1982 or thereabouts.

The main issue is a safety one - if a part of the body is underneath the wing as it comes down on the support, then serious injury can occur. Imagine someone jumping, sitting down or falling on the wing as their hand or foot slips between the wing and the support. The same leverage that makes wings attractive then also makes them lethal.

If I recall correctly, one of the top 18 Foot Skiff pros (Dave Stephens???????) lost a finger in this way.

As you say, Petros, extra dihedral does the same thing without the hassle, expense and danger of pivots.
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  #107  
Old 04-09-2012, 06:43 AM
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The pivoting wing can be designed so that it is physically impossible to get an appendage of the human body pinched using a combination of shockcord and limit lines from inside the boat or a supporting wire + shock cord from the mast. Substantial clearance under the seat would be designed in by reducing side height in way of the seat-no posiblility of anything being pinched between the boat and the seat with the right design. The advantages are great in allowing the weight to windward to be lower while the amount of pivot can be adjusted(see sketch below). A straight pivoting "seat" will be simpler to construct than one with dihedral. Poor design in the past does not ,necessarily, equate to poor design now. Thanks for pointing out those mistakes.....

PS- Petros would a "trapeze" wire supporting the end of a pivoting seat be illegal since it doesn't directly support the person?

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New low-cost "hardware store" racing class; input on proposed rules-seat-pivoting.jpg  
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  #108  
Old 04-09-2012, 01:48 PM
Petros Petros is offline
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Doug,

Yes, that would likely be fine. The idea is to keep the entrants simple and safe, a trapeze is not really part of the boat and adds both expense and a certain level of skill to use (I have used them, fun but occasionally went for a swim in rough conditions, sheer luck I was not run down in a race). Something attached to the boat hull does not present the same kind of issue. If I was a judge, I would allow it. I hope to also build and enter, not be a judge, so that would be up to the local race official. But I see no violation of the rule intent.
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  #109  
Old 04-09-2012, 02:34 PM
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Originally Posted by Petros View Post
Doug,

Yes, that would likely be fine. The idea is to keep the entrants simple and safe, a trapeze is not really part of the boat and adds both expense and a certain level of skill to use (I have used them, fun but occasionally went for a swim in rough conditions, sheer luck I was not run down in a race). Something attached to the boat hull does not present the same kind of issue. If I was a judge, I would allow it. I hope to also build and enter, not be a judge, so that would be up to the local race official. But I see no violation of the rule intent.
======
Great! I have used such a system for years on RC models where the trapeze wire supported "rack" not only pivots but also slides. If you take the sliding facility away ,it becomes really simple, easy to build and safe to use. For singlehanded "sit-in" versions the seat could allow ballast to be moved inside the seat.
Attached Thumbnails
New low-cost "hardware store" racing class; input on proposed rules-tantra-heli-big-ungava-scow-012.jpg  New low-cost "hardware store" racing class; input on proposed rules-m24c6_asy-spin-pbs.jpg  New low-cost "hardware store" racing class; input on proposed rules-pbsdemo.jpg  

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  #110  
Old 04-09-2012, 05:14 PM
CT 249 CT 249 is offline
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On the other hand, a simple trapeze line adds virtually no expense, compared to sliding seats, even when using the cheaper VJ-style sliding seats (which present their own pinch problems that no one has managed to eliminate in reality AFAIK). And sliding seats tend to create many handling issues, since (much as some of us love them) they are arguably harder to handle through tacks, gybes and launches.

Of course, the extra expense of a sliding seat will be caught by the spending cap, but to allow the complex seat and not allow the cheap and light trap may not be ideal.

Pedros, please don't see these comments as negative; it's just that it's surely better to run through these issues than to ignore them. Racing classes and racing rules have a reputation for outlawing bright ideas, but when we look at the historical record more closely it often turns out that the ideas have been tried and found wanting in various ways. And rule sets are often a classic example of the law of unintended consequences in action. Ban traps, for example, and you may end up forcing any serious competitors into using more complex devices or else having to create a design that is compromised in other ways by the lack of trap power. And these areas have already been explored in detail by the ISAF singlehander trials; it's not as if the sailing establishment has ignored such things.
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  #111  
Old 04-09-2012, 05:26 PM
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On the other hand, a simple trapeze line adds virtually no expense, compared to sliding seats, even when using the cheaper VJ-style sliding seats (which present their own pinch problems that no one has managed to eliminate in reality AFAIK). And sliding seats tend to create many handling issues, since (much as some of us love them) they are arguably harder to handle through tacks, gybes and launches.

Of course, the extra expense of a sliding seat will be caught by the spending cap, but to allow the complex and heavy seat and not allow the cheap and light trap may not be ideal.

Pedros, please don't see these comments as negative; it's just that it's surely better to run through these issues than to ignore them. Racing classes and racing rules have a reputation for outlawing bright ideas, but when we look at the historical record more closely it often turns out that the ideas have been tried and found wanting in various ways. And rule sets are often a classic example of the law of unintended consequences in action. Ban traps, for example, and you may end up forcing any serious competitors into using more complex devices or else having to create a design that is compromised in other ways by the lack of trap power.
==============
As far as I know, no one was talking about using a sliding seat. My personal opinion is that a sliding seat on a boat built to this concept would use too much of the budget though it would fit the rules while having a high effective beam.
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  #112  
Old 04-09-2012, 05:33 PM
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Originally Posted by Petros View Post
Doug,

Yes, that would likely be fine. The idea is to keep the entrants simple and safe, a trapeze is not really part of the boat and adds both expense and a certain level of skill to use (I have used them, fun but occasionally went for a swim in rough conditions, sheer luck I was not run down in a race). Something attached to the boat hull does not present the same kind of issue. If I was a judge, I would allow it. I hope to also build and enter, not be a judge, so that would be up to the local race official. But I see no violation of the rule intent.
======
Petros, as a suggestion, it seems it would be better to have one "central" judge so that "officious" local authorities didn't try to stifle innovation. Plans, pictures, even video could be submitted in advance so no one gets the axe after their investment in time, not to mention their $300 investment. You say it's ok to use the trapeze wire supported pivoting seat, so I build it and then some local guy(s) rule against it. Consistent application of what is and is not legal is absolutely critical, in my opinion.
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  #113  
Old 04-09-2012, 07:26 PM
Petros Petros is offline
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I understand the issue, one of the "behind the scene" actions I was planning on incorporating is to have all of the local chapters and judges issue reports w/pictures of anything they find questionable, no matter if they conditionally approve it or not. With these reports we can put out a policy statement for every local chapter to review to try and keep the rule judging consistent. Might also results in rule changes or clarifications for next season as well. The guideline will be to conditionally approve it, but report it so we can see how far people are pushing the rules, and if clarification is necessary. It may not be a competitive design anyway and it is a moot point, but we do want each local chapter to enforce the rules fairly and consistently.

The issue I have with a trapeze is it is not really part of the boat, it something you wear, unlike a bench or hiking strap. Also, the idea is to develop fast PRACTICAL boats, and like spinnakers, a trapeze is not really used outside of racing. I have used them and find them fun, but not really part of the boat. Do we include it as part of the cost of the boat or not? How would it fit in the box rule? I think it is easier just to not allow them. I might change my mind later, but it tends to cause a very different type of boat to be built than one designed without them. It would be a good thing to include in a multihull class (with less restrictions) in the future, more common with smaller multihulls anyway.

BTW, based on the input from this thread, I recommended raising the cost limit to $600 to allow better boats to be built and allow more design flexiblity. Our next meeting over rule formulation is May 6th. So you have until than to contribute.
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  #114  
Old 04-09-2012, 07:44 PM
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Originally Posted by Petros View Post
I understand the issue, one of the "behind the scene" actions I was planning on incorporating is to have all of the local chapters and judges issue reports w/pictures of anything they find questionable, no matter if they conditionally approve it or not. With these reports we can put out a policy statement for every local chapter to review to try and keep the rule judging consistent. Might also results in rule changes or clarifications for next season as well. The guideline will be to conditionally approve it, but report it so we can see how far people are pushing the rules, and if clarification is necessary. It may not be a competitive design anyway and it is a moot point, but we do want each local chapter to enforce the rules fairly and consistently.

The issue I have with a trapeze is it is not really part of the boat, it something you wear, unlike a bench or hiking strap. Also, the idea is to develop fast PRACTICAL boats, and like spinnakers, a trapeze is not really used outside of racing. I have used them and find them fun, but not really part of the boat. Do we include it as part of the cost of the boat or not? How would it fit in the box rule? I think it is easier just to not allow them. I might change my mind later, but it tends to cause a very different type of boat to be built than one designed without them. It would be a good thing to include in a multihull class (with less restrictions) in the future, more common with smaller multihulls anyway.

BTW, based on the input from this thread, I recommended raising the cost limit to $600 to allow better boats to be built and allow more design flexiblity. Our next meeting over rule formulation is May 6th. So you have until than to contribute.
-------------------
My opinion: no trapeze unless the wire is supporting part of the boat-like the seat.....
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  #115  
Old 04-10-2012, 12:32 PM
CT 249 CT 249 is offline
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The issue I have with a trapeze is it is not really part of the boat, it something you wear, unlike a bench or hiking strap. Also, the idea is to develop fast PRACTICAL boats, and like spinnakers, a trapeze is not really used outside of racing. I have used them and find them fun, but not really part of the boat. Do we include it as part of the cost of the boat or not? How would it fit in the box rule? I think it is easier just to not allow them. I might change my mind later, but it tends to cause a very different type of boat to be built than one designed without them. It would be a good thing to include in a multihull class (with less restrictions) in the future, more common with smaller multihulls anyway.
.
Traps are very common outside of racing in many areas; look for example at the Hobie 16, which rates about 3rd most popular boat of all time and comes with traps despite being designed as a beach toy. And top-selling plastic boats like Hobie Getaways and Topper Topazs etc come with optional traps.

Sliding planks/seats/stay supported seats and wings are almost certainly much less common as well as being much more complex, and they almost certainly have pretty much the same effect on boat design.

If a trapeze hanging from a mast is "not part of a boat" then what about a traditional pry board style of hiking plank, which is basically just a piece of timber stuck under the leeward gunwale and extending over the windward gunwale? Would you be allowed to use this very simple system instead of the complex sliding seats that you will allow?? If so, why is a loose piece of timber that may not be connected to the boat considered "part of the boat" when a trap wire is not "part of the boat"? If the problem with a trap is that it requires a trap belt that is not "part of the boat" then what about the old "bell rope" idea, and what other restrictions on crew's clothing are to be brought in?

Anyway, it's your rule but if you are trying to encourage practical small boats you may find others asking why you allow the more complex sliding seats of various types (and I love them, tbh) but not a piece of string and (say) a PFD fitted with extra webbing to form a harness. I am not trying to discourage, merely coming at the proposed rules from different angles in an attempt to test them and foresee what could be said of them.

At the moment it appears that a modified Lust Puppet or Clark ply International Canoe (built 1' shorter and expertly out of cheap materials) or a giant skiff Moth would be extremely hard to beat because allowing planks/seats etc allows you to have a hull just 1 to 3 feet wide. Such a boat may not be what you are trying to create.


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  #116  
Old 04-10-2012, 01:24 PM
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CT,

You bring up some good issues, we will have to discuss them. One foot wide hulls with hiking planks are not very practical boats, but rather just designed to go fast. It is entirely within the rules as stated to make a vary narrow hull with a hiking board that is at the box rule max beam, and than have it shift side to side. It violates the intent that I have. Though I am temped to keep the rules simple without restrictions, if we end up with extreme designs that win, but are not practical day sailors, it is not the ultimate goal I was working towards.

Any suggestion on how to keep the design of the boat practical? Should we design events where this type of device does not give an advantage? All appendages of the hull have to be fixed? There are also safety aspect to this as well.

Thanks for your input.
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  #117  
Old 04-10-2012, 04:05 PM
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All boats are compromises, but have to have a main purpose or use.

If it's your intention to encourage design innovation, then an open experimental racing class will do that. But limiting spending, undoes it just as fast.

I know your original concept was anything goes in a $300 budget!

I suspect you'll end up with a lot of styrofoam sail boards with pvc masts and visqueen sails.

But good luck.
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  #118  
Old 04-10-2012, 04:26 PM
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Petros, I was suggesting a fixed, pivoting seat. Banning sliding seats makes sense but may not be necessary because building one within the existing rules would be difficult. You also have to be carefull about encouraging innovation, then banning the winners.......
If you are going to allow any method of extending crew weight other than the hull, the natural design tendency is to reduce hull width which also reduces cost--and ease of sailing.
Design innovation always is frought with danger in a class of amature builders:
some guy builds a narrow boat with a pivoting seat and DSS and the other guys cry foul because it wins or more likely because it might win.
So, you have to decide if you want design innovation which is not everybodies cup of tea. Building innovation is already encouraged by the rule(still think $300 is too low).
My vote is to allow innovation with some restrictions like those you already have but including:
1) no sliding seats: if it could be built within the rules it would allow an effective beam much greater than 8' since the seat could slide to windward say, 6'+ with the boat still 8' wide.
2) Maybe: minimum beam at the waterline of 2'-2.5'? I'm not really for this but it is worth considering. You slide done a slippery slope with this kind of restriction.
3) No hiking-you have to sit up. Easily enforced by prohibiting hiking and hiking straps. (see post #120)
-------------------
Again, do you want "design innovation"( and the problems that come with it) or do you want to limit the class to just building innovation?
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  #119  
Old 04-10-2012, 04:36 PM
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CT,

You bring up some good issues, we will have to discuss them. One foot wide hulls with hiking planks are not very practical boats, but rather just designed to go fast. It is entirely within the rules as stated to make a vary narrow hull with a hiking board that is at the box rule max beam, and than have it shift side to side. It violates the intent that I have. Though I am temped to keep the rules simple without restrictions, if we end up with extreme designs that win, but are not practical day sailors, it is not the ultimate goal I was working towards.

Any suggestion on how to keep the design of the boat practical? Should we design events where this type of device does not give an advantage? All appendages of the hull have to be fixed? There are also safety aspect to this as well.

Thanks for your input.
Herein lies the problem with prolonged analysis of any kind - paralysis. There is no more dangerous phrase to project progress than "What if?".

No matter how tight the rules, or how well written, the rule-beater segment of the population will undermine the intent of the rules faster than election promises disappear after the votes are counted. The less rules you have, the less ways people can get around them.

I'm more of the position that you should clearly state the intent of the design, and leave discretionary "membership" in the class association up to the official measurer at the actual events. If the measurer feels a design is outside the intent of the design, too bad so sad. Just pick the measurers carefully and make sure they are on the same page.

I'd go with your box rule, say it is a monohull (if that is your intent), say hiking is the method of augmenting righting moment (no wings, no sliding seats,no traps, etc.)

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  #120  
Old 04-10-2012, 04:49 PM
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Herein lies the problem with prolonged analysis of any kind - paralysis. There is no more dangerous phrase to project progress than "What if?".

No matter how tight the rules, or how well written, the rule-beater segment of the population will undermine the intent of the rules faster than election promises disappear after the votes are counted. The less rules you have, the less ways people can get around them.

I'm more of the position that you should clearly state the intent of the design, and leave discretionary "membership" in the class association up to the official measurer at the actual events. If the measurer feels a design is outside the intent of the design, too bad so sad. Just pick the measurers carefully and make sure they are on the same page.

I'd go with your box rule, say it is a monohull (if that is your intent), say hiking is the method of augmenting righting moment (no wings, no sliding seats,no traps, etc.)

--
CutOnce
------------------------
A rule like that would surely reduce participation by any of those that have ever done serious hiking. It is a nasty way to get RM,
when there are so many better solutions for the human body. In fact, banning hiking(you have to sit up) is probably a good idea-I'll add it to my list above(post #118). When I was a kid I built an Elvstrom hiking bench and could easily outlast heavier people-you can't beat someone who has trained for "hiking out" if you haven't......
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