I use a 1/16 (2mm) inch piano wire for the shaft, and folded the end over about 3 cm as tightly as possible. The other end was left long enough to extend into the hull for the tiller.
The sides of the rudder were 2mm (1/16") balsa about 4x7 cm (1.5"x2.5"). The wire is sandwiched betwen the sides at about 40% from the front, and the bottom and fore & aft adges are taped well to prevent leaks. Then I dripped thin Cyano in the gap between the sides, followed by a spritz of kicker.
After the resin cured, the tape was removed, and the rudder sanded to shape( I like a sweept-back hape.) Then sealed with my favorite water-based clear.
My next operation is to make a tiller arm by soldering a 1/16" wheel collar to a piece of sheet brass, about 5x 25mm.
I might want to try a longer rudder or a spade-style later.
all I need now is to make and mount the rig. Then sneak over to the apartment complex down the road to borrow their lake.
I hope that you are aware that piano wire is a high tensile steel but not a stainless steel. It is prone to rust, perhaps not as quickly as mild steel but it will oxidize eventually. I use stainless for my rudder shafts, but if you prefer piano wire you’ll need to seal it somehow (unless this is just a quick experiment to determine if your rudder shape works well). One product that I’ve used to waterproof my electronics is “Aeroplate” (www.aerotrend.com) which I bought at an R/C show a couple of years ago. Now I don’t know how quickly it would wear off in a friction situation like a rudder shaft in a rudder tube but it might give you some level of protection against rust and freeze-up.
I’ve also seen mention in these threads of guys building rudders with aluminum shafts to go in brass rudder tubes. Don’t do this! If the water you sail in is slightly alkali (like pool water, or water that might see fertilizer run off from lawns, or brackish or saltwater) then you have the chemistry for a battery. Your rudder will freeze up in the shaft in a matter of minutes and you will not be able to remove it. The rudder and shaft will have to be cut out of your boat. Believe me, thirty years ago I learned that lesson in a race away from home. It bagged my weekend.
I’ve seen quite a few photos both here and on the Footy site that show boats with rudders that are angled aft. I don’t recommend angling the rudder shaft aft, even to take advantage of the extra two inches allowed aft of the hull. By angling the shaft aft the rudder functions like a paddle, deflecting water up or down as much as directionally. The paddle is actually a good analogy. If you picture a paddle over the side of a canoe with the paddle shaft held vertically and twist the paddle right or left it acts like a door swinging on a hinge. Now if the paddle is tilted aft and rotated around its shaft the water it redirects is deflected up or down as much as it is steered in one direction or the other. The resulting action for a tilted rudder shaft is reduced turning effect and increased drag. In addition you’ll need a larger rudder to get the same amount of steer as a smaller rudder with a near vertical shaft.
One last thought on tilted rudders, they effect a boat’s trim. Picture sailing upwind, the boat is healed. When you make an adjustment in direction away from the wind the rudder acts not only to turn the boat but deflects some water upward. The effect this has is to push the bow down, something that we’ve all observed. With a steeply angled shaft this situation is amplified, because the rudder deflects water when the boat is not heeled. This further, or more radical depression of the bow during course corrections changes the trim more than necessary, meaning that the boat will take longer to rebalance itself. Perhaps this will only take a fraction of a second longer but those fractions will add up around a race course.
The better solution to take advantage of the two inches allowed for rudder overhang is to mount the rudder on the stern with the shaft near vertical. Unfortunately, when the rules were rewritten to put the Footy in a box there was no provision made for a rudder linkage for a stern mounted rudder. So, while the original rules allowed stern mounted rudders the new box rule prohibits them through the omission of a space allowance for a linkage system. Instead it encourages a less efficient and detrimental means of mounting a rudder for better hull balance. This is one of the things that should be addressed when the rules come under review. Now that we are qualified to be an AMYA class we should be able to speak with a unified voice to fix some of the box rule’s problems.
Those arethe same reasons I like to angle my rudder ( on my ODOM) to push the stern down in case the bow goes under. If I thing the bow is getting too low, or it dives, a little flick of the stick will pop the bow back up.
But for now, I’m trying to keep the rudder shaft as vertical as possible.
Tomo, I think Niel’s comments regarding rudder angle are well worth paying attention to…good advise.
Neil, I really have a great appreciation for your experience and knowledge of the sport. I doubt that you know how much I mean that. I am a bit tired, though, of your criticism of the box rule. I’m genuinely sorry that your Bantam was obsoleted by the box rule, but it has been grandfathered into the class despite it’s wider beam.
Everyone is entitled to their opinion regarding the class rules, and can freely express that opinion here, but I hope we can generate positive, rather than just negative critique.
Depending on how all the other factors like bow vs. stern freeboard come together, stern mounted rudders can be made within the rule. Graham has one on his Kittiwake, which appears to fit the rule, and seems similar to your linkage approach. It appears to me from photos of your Bantam, that the rudder linkage would fit the box rule if it were raised up closer to deck level. Where I do see a potential problem is if the bow is made significantly higher than the stern, and a stern-mounted rudder is also part of the design…but that is an example of the many design tradeoffs that need to be considered when building, not necessarily a condemnation of the rule. I have a stern mounted rudder that fits the box rule on one of my boats. It isn’t the solution that you have used, and perhaps people would prefer your approach. If so, let’s hear a proposal for positive change, please, rather than just accusations regarding the current rule. Perhaps a rectangular cutout, rather than triangular, would allow room for more linkage options?
Now that we have established a new AMYA class, we have the option to change the rules based on AMYA procedures. We could opt to go our own way, like the US One Meter class, or we could opt to conform to an International approach, like the IOM class. Everyone’s opinions will have an equal opportunity, and all AMYA class members will have a vote. I’m certainly in favor of us speaking with a unified voice, but I hope it will be a positive one. Critique alone won’t change anything.
Here is a pic of the new transom rudder I have put on my cat boat Kitty. As of right now untested. Similar to Graham’s but done in brass.
I have to agree that making the shaft out of piano wire is not a good idea due to rust, keep it oiled! I also would worry about such a small diameter shaft flexing under strain. Disimillar metals of any sort involved with water promote chemical reactions. If you really looking for strength get some bronze wire, or try stainless on stainless tubing. Personally, I use brazing rod from welding shops, it is much harder than the brass that you get at hobby shops.
Just to confirm that the transom mounted rudder on the Kittiwake design does indeed fit within the rules box triangular cutout.
I did briefly think that the MYA/AMYA box allowed too little space for a transom mounted rudder linkage, but in practice I found that it was not difficult to comply… bearing in mind the bow height as Bill mentioned.
In our brand new little club here in Wisconsin we are agonising over which 1 metre to adopt, ODOM, US1M, IOM… a hard decision which would be so much easier if there was only an IOM, which is pretty much the case in the rest of the world.
This is relevant to me because we are at the point where we could have a USFooty by changing the box rule. I would much rather see us go with an international rule by not changing the box.
I do of course have a small commercial interest as my cottage/basement industry ScaleSailing.com is about producing Footy kits and accessories. Obviously I would rather all of the potential Footy market required the same boat… But if I may put that aside, I simply think that with the internet drawing us all together we can grow this class more quickly if we all build to the same rules box.
i would have to agree, the multi chine hull of the razor footy would be my choice, any chance theres a foam footy like that in the works?? im trying to get one build, maybe 2, to get my flying club into sailbaot racing and the simplicity of this small craft is so nice…
Hi Mike… at the moment the answer to your question is, no. With the method I am using to cut the cockpit area in the core the keel chine joint would be unsupported for about 2/3rds of it’s length and we would be back to the problem of making that edge to edge joint again. The key reason for my developing the foam core hull is to avoid having to make any such joints.
Having said that… it is far from impossible and something for me to work on once I have the Kittiwake and related designs on the market.
sounds neat, i will probly get one of the kits once you have them out, as far as cutting chines, i wonder if a soild block foam, iv been cutting flaots for airplanes inthe last weeks, and makeing a keel ridge then panaling the sides, heres the mini bob about with chines added, i just cut the deck plane in half, seemed to work good…
In regards to Graham’s comments about maintaining conformity to the new Footy box rule I would like to make several points.
_First, does Graham do all his measurements in inches, pounds and ounces, or in conformity with the International standards in metric units? The metric system has not had all that much success in getting a toehold in the US.
_Second, the box rule was implemented by caveat. I have been monitoring internet sailing sites for a long time and designed and built my Bantams to the previous rule close to three years before the rule change was announced. I was told that the gentlemen who changed the rules to this box rule took into consideration all the existing designs at the time before making the changes. However, there was no internet discussion about the changes being proposed that I saw and no broader feedback invited, and no democratic process involved. And no explanation for why changing the rules was necessary in the first place.
-Third, professionalism issues aside, rules are meant to evolve as problems with them arise. Outright scrapping of one set of rules for another has not been done in the thirty-five years the I’ve been sailing model yachts. But it was done this time to alter the nature of the class from a design class to a restricted class. The only other class that uses a box rule (the favorite rule of one of the guys that authored the new Footy rule) is the 36R class in the UK. That “R” stands for restricted. The change over is great for professional builders who want restrictions to protect their investment from the innovations that crop up when freethinkers tinker with new concepts in a design oriented class. Thats why, referring back to Graham’s club meter long boat choices, the IOM is more popular around the world than any other boat class. But, please note, nobody homebuilds IOMs anymore. Not if they expect to be at all competitive. So, should Footies be like IOMs and the rule favor professional boat builders or should the rule protect and encourage the tinkers and homebuilders? You all may not think that this is much of an issue right now, at the beginnings of the class, but I think that it is an issue because it sets the tone for the direction that the class will follow. Right now the US is one of the stronger regions of growth for this class so with AMYA class affiliation we can influence the course of the Footy.
Now before I get criticized by Bill or anyone else for not liking the box rule, or rocking the boat, or bringing up for discussion things that others don’t want to consider please think about why I would spend my time writing about these issues. I feel that the origins of the class and the decisions that are made on behalf of all of the class’ participants should be common knowledge, not just to those who have followed my discussions on these threads, but to those who are newly logged on and think that the rules in their current form are written in stone and that there is no room or reason for debate.
It would be great if everyone reading this took out a copy of the box rules and looked it over carefully. After each paragraph consider not only what that paragraph describes but why it frames its language the way it does and how it relates to the overall qualities of the class they are describing. Think about what is not allowed in the class and what you would like to see the class become. Then if you have questions about why things are one way and not another post those queries (no matter if you think they are basic or uninformed or whatever) for the rest of us to respond to.
Niel, and any others to whom I’ve given the impression that I’m unwilling to allow debate on the rules, I apologize. I believe healthy debate will result in the best set of rules for the majority of class participants.
What I have tried to encourage (and will continue to do) is positive, rather than negative, approaches to the discussion. Changes can only occur when improvement suggestions are made.
I’d also like to encourage people to be clear when expressing an opinion (which all are entitled to) as opposed to a fact. That will help clarify the issues under consideration for change.
Back to the original topic, I mentioned earlier that I had some concern about being able to make a stern-mounted rudder on a boat with a significantly higher bow than stern. I decided to play with Razor to see what might fit in the box.
The pics show cardboard extensions of Razor that could be done within the constraints of the box rule. Although I admit that cardboard isn’t quite the same as the real thing, I think it’s reasonable to conclude that her bow (with a minor mod to the angle) could be raised significantly, and still fit in the box with the extended rudder shown falling well within the box limits. The square piece of cardboard on top of the rudder is intended to show the limits of the linkage that would reasonably fit within the “V” of the box.
By the way, if you guys haven’t made a box yet, I suggest you do. It doesn’t have to be fancy…cardboard will work OK. You might find, as I have, that while the box restricts you (and what other development class doesn’t have restrictions?) it may also inspire you to see possibilities you might not have otherwise discovered.