Can’t post the righting/heeling moment spreadsheet, pm me and I will email to you.
I have AutoCad drawings and photos of my F100CBTF showing a gear quadrant rack and pinion drive system, once again pm me and I will send them out.
I like seeing people taking on challenges such as gappy yachtie2k and youself.
It’s a bit like the caveman who throught outside the square and came up with the wheel.
USA2
Ah nows that where you have a problem and looking at it in the wrong way.
With the RC canting keels boats everyone goes i am going to build a boat that is so long and have heaps more sail area than a normal boat of that size and put on the same keel that this boat would normally have and cant it. This is I believe wrong the thing here is the boats can carry the area up wind but as soon as you turn the corner it will nose dive like you won’t believe as it is to over powered. The thing to do is take a boat for example 1 metre long take the standard sail area for this size boat put a canting keel in it but put a light bulb on it taking weight out of the boat and this will make u faster and you will be able to turn the corner. I have found this and so has Grunta and the lighter the keel the better the boats went as well as I took 400 grams off my original boat and it made it ten times better and Grunta took some off his and it went heaps better as well. Hopefully he will come on as well and explain more what he found.
Cheers gappy
<blockquote id=“quote”><font size=“1” face=“Verdana, Arial, Helvetica” id=“quote”>quote:<hr height=“1” noshade id=“quote”>Originally posted by Roy Langbord
A minor word of caution, particularly if you are knew to design and building r/c yachts. While there is some talk on the internet about r/c sail moving ballast systems, (and even a few experiments here and there), no one has yet produced a fast, reliable r/c moving ballast system that has proven itself out on the racecourse.
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Actually, Roy, this is not a completely true statement any more. About 4 years ago, a guy won the Mini40 class French Championship with a movable ballast system on his Trimaran. By all accounts, the system works very well and is fast enough and reliable enough to use in RC racing. Since then quite a few of the European Mini40 sailors have been experimenting with moving ballast systems. Some work better than other, but quite a few of them work well enough to give their boats a speed advantage.
As far as movable ballast systems here in the US on monohulls, your statement is basically true, but is also the result of the fact that the class rules for many classes do not allow movable ballast. This has had the effect of discouraging development in this area and thus our brightest technical minds have not been working on these systems.
But there are 2 classes that allow this rule to be “bent” slightly - the US1M and M class. Both classes allow canting rigs which result in a similar set of physics as a canting keel. In both classes there has been a limited amount of development in that area. In the M class, Dario Valenza from Carbonic boats (Aus) build a canting Rig M and raced it. He claims it was the fastest M he had ever built, but he struggled with some control problems. In the US1M class, Hal Robinson built a canting mast boat and has had a lot of good things to say about that boat’s performance in racing situations.
So the idea of movable ballast has been tried and has proven its potential on the racecourse. It has not become mainstream, that is for sure. But to say that no one has done it is just not true.
Will Gorgen
Edited for spelling
Come on Will. What I said about moving ballast in r/c sailing was (i) there have been “a few experiments here and there” but (ii) no one has yet produced a “fast, reliable…system that has proven itself out on the racecourse.”
For you to suggest (particularly to someone knew to r/c sailing) otherwise or that canting ballast is currently a “proven” technology is off base. And to use anectodotal evidence from “canting rigs” to try to make this point is even a further departure from the facts. Fact is Hal Robinson’s canting rig boats have never won a major US1 race. Fact is that in the substantial amount of time I spent with Dario from Carbonic in New Zealand, he made it pretty clear that his canting rig M while at times fast (in his eyes) it was also usually so unbalanced as to be non-competitive and he abandoned the project. Fact is you have been working on a canting rig boat for at least a year now and it hasn’t sailed yet. Fact is that in the mini forty class moving ballast is as I said an “experiment” and is not widely used and has certainly not been used on most of the recent class winning boats.
Look, the point I have been trying to make here isn’t that far from what Gappy has suggested. Moving ballast systems are currerntly at the “gee whiz” nice gadget stage in r/c sailing. There is no “standard” on how it should be done, no extensive track record of what works and what doesn’t, no proof of how fast the systems are. To successfully build one is quite a project, a real accomplishment, and something to be taken on by someone with design experience and a lot of time on ther hands.
When someone who is clearly a beginner to r/c sailing comes onto the net and wants to build a “hi tech” boat to beat an “EC12 in light air”, I thought it reasonable for at least someone to suggest that this goal could be easily accomplished without developing from scractch a moving ballast system.
For those like John B and Gappy and Grunta and Will who are experimenting with moving rigs and keels etc., I wish you all good luck and always look forward to hearing about the results of your work. I’ve gotta believe that someday, someone is going to get this stuff to a place where it could be reliable and fast for r/c sailing. But come on guys, please, particularly for the newbies, be realistic, practical and honest in letting people know that this is all still very experimental stuff and that you have to learn how to walk before you can try to fly.
Although I am new here. I find the atmosphere here seems quite hostile. It seems that just because Gappy and a few others want to build canting keep boats, as I do. Many others want to tell them they are wrong. When in fact they are most often building for their own satisfaction. I hve never raced an RC boat before, I have sailed one a few times, but I find the CBTF technology quite amazing and would love to have an RC boat with that capability. Plain and simple, they may be faster, they may not, BUT it is the only way it may ever have the possibility of advancing and BECOMING faster. Other people experimenting on their own in the face of nay-sayers. Congrats to Gappy and others who continue to experiment.
Andrew Miller
Roy,
I would hardly consider winning the French National Championship in the Mini40 class an “experiment”. I would consider that system to have “proven itself on a racecourse”.
Gappy has been pretty clear that his stuff does not fit within the rules of existing classes and that his stuff is experiemntal. He has shared some of the lessons that he and Grant have learned through trial and error.
Speaking of Grant, I have heard that now that he made his boat lighter that it is a rocketship. I’ve heard that he is able to beat state of the art IOMs in most conditions and at least keep up in the conditions that favor the IOM. This boat is in production. I’m sure that Grant made sure the boat was reliable before he made it available for sale.
I have spoken with Dario many times as well and he has been very helpful with my US1M design. There are a few things that he had to do that made his boat especially complex: By having the hinge point of the mast down on the keel, the axis that the rig canted about was not the same axis that his fairleads for the sail passed through. Thus he had to move his fairleads with the rig and added a lot of complication there. I have elected a slightly simpler path. I have put all the connections along the same axis. The mast pivots at the deck. The jib pivot, jib fairlead, main fairlead and backstay attachment point are all co-linear so as I cant the mast, none of the rig tensions or trims will change. This simplifies things a lot.
People are figuring out some unique solutions to the many challenges associated with movable ballast and canting keels/rigs. And we are having fun doing it.
You are suggesting that USA2 is too new to model yachting to be able to try something so “hi tech”. Have you asked USA2 about his sailing experience? Maybe he is a proficient sailor and modeller. Have you considered that some people like to try new stuff? Have you considered that maybe he is willing to accept that the system doesn’t work perfectly?
You suggested that his boat would be pretty close to a Marblehead and suggested he may want to try that class. He didn’t show much interest in that idea. So clearly, he does not care much about racing and trying to conform to a class.
I think we have been pretty honest with USA2. He clearly doesn’t want to “race” against his buddy with the EC12, or he would have gotten himself an EC12. It sounds like he wants the challenge of doing something new and seeing how it works against tried and true technology. More power to him!
Will Gorgen
I had got the nod for attaching Excel worksheets.[:-propeller]
Have fun with it[:D], you can see the advantage of having a canting keel.[:-jump]
Sorry Roy but technology will advance oneday.[:-paperbag]
Download Attachment: [ RM Metric & Imperial.zip](http://www.rcsailing.net/forum1/data/JohnB/200521143029_RM Metric & Imperial.zip)
3.85KB
Roy
I am with you in that I hope one day we do get these keels to a degree of reliability but in saying that i have not broken anything on my boat and have not had to modify anything since launching it but obviously my second boat is a bit different.
But I do believe that one day we should be able to get these going fast enough to keep up with a boat of the same size with a fixed keel.
Any way leave u guys to it.
Cheers Gappy
Gappy, thanks for understanding my point. As I said I look forward to hearing of your progress.
JohnB, I too hope technology will advance some day, my only point is that the day isn’t here yet, especially for beginners to r/c sailing.
Andrew: CBTF sure is fascinating technology and it would be great to see it perfected for r/c sailing. The hostility you sense is leftover from some old b/s from a guy who used to dominate this board. But your post sort of makes my point about newcomers and yet to be developed technology. To obtain the advantages of canting keel technology besides simply working out the mechanics of the canting keel you also need to design an appropriate hull, figure out the design and placement of the foils, and design and locate the rig. This is all a pretty tall order for someone new to sailing and r/c yachts. Nothing is impossible, but the liklihood of success for such an endeavour from a newcomer is very low. On the other hand, if your idea of fun is to build a boat that looks like an off shore racer and has a keel that swings around, your liklihood of success is much higher, but even then there are some real technical issues involved in simply building a keel cant mechanism, usually beyond the ability of most beginners. I guess I thought it only reasonable to let people know in advance. Think of an analogy to r/c planes. If you had never designed or flown an r/c plane before wouldn’t you want someone to tell you that the liklihood of success of you designing building and flying your own original r/c jet turbine plane was pretty low and maybe you should look into somethng else first.
Finally, Will, you of all people should know better particularly when dealing with beginners. Just your description of some of the issues involved with sheeting a canting rig are beyond most newbies. (And you haven’t even addressed the serious balance issues that Dario encountered with his Marblehead.) Heck, you’ve been around r/c sailing for some time, and you’ve been working on your caninting rig boat into a second year now and it hasn’t sailed yet. How long do you think it would take someone with limited experience to acheive satisfcation? All I’m tyring to suggest is that to encourage beginners without at least telling of the difficulties of the process is kind of negligent.
Roy,
Thank you for that heads up. I do however have a lot of sailing experience and a decent amount of schooling in fluid dynamics, hydrostatics and hydro dynamics. I am a recently graduated engineering student, so I understand your assumptions and Im not saying they are beyond me, but Im willing to take the risk on the account of my experience and knowledge.
As for the boat, it started out with the idea of making a boat that resembles Pyewacket from the waterline up. Since the boat is more or less going to be hand built with the help of a “carbon expert” friend, I figured why not take a little extra time, effort and research and make it as close to the full scale boat as possible. With that said, this is most likely the first iteration of many, that have undoubtedly started a long process. Thanks again.
Andrew Miller
the boat Im building isnt being specifically designed to any rule. The concept is to get the most speed out of the hull that I have. I have been sailing Soling 1meters for quite a while, and also race on full scale boats. I was experimenting with keel types on the solings, but then decided I wanted to mess around with the canting keel stuff. A couple years ago when the CBTF technology was starting to become well known, I made a static model of a boat with a winged canting keel, that is very similar to what Ian Murray has designed in Australia. Im probably the youngest person on this forum, but Ive been on/around sailboats all my life. I do appreciate how some of you have considered newcomers, but in this case Im just a newcomer to this forum, not the whole sport of R/C sailing.
<blockquote id=“quote”><font size=“1” face=“Verdana, Arial, Helvetica” id=“quote”>quote:<hr height=“1” noshade id=“quote”>Originally posted by USA2
the canting keel boats would be faster in moderate winds, especially beam reaching. It also would allow you to carry more sail area for the size of the boat, so therefore would almost always be faster
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Pretty much what I would suspect. However, factor in that you have an upwind leg a reaching leg and a downwind leg - and your reaching leg is only 1/3 of the course. Now factor in that the reaching leg is (usually) only about half or less the length of a windward or leeward leg. Finally factor in that often a course is S-W-R-L-W-L-F and that reaching leg becomes rather immaterial in context with the rest of the legs. This is the point I guess I was eluding to - and as in multihulls (strictly an example here) I would expect the multihull to be twice (?) as fast as a monohull on the reaching leg. Now if the thing isn’t designed to point and tack, and if buoyancy is such that downwind we have an extreme stability problem, then what appears fast on paper (wide beam, lots of sail area, extremely light weight) may not be so in practical sailing.
Thanks, by the way, for the comment on the Wind Warrior. A true on-water comparison is what will really show the difference if boats are (generally) equal and if a canting keel makes sense. Now to convince the classes to allow a “canter” to play along to see what happens in real time is the next challenge !
Dick,
in real canting keelers, they sail downwind by gybeing back and forth. I would assume that if you sailed a RC model with an oversize rig downwind, the thing might possible be fast enough to avoid sailing dead downwind, and therefore be able to sail efficiently downwind. One problem as you mentioned is the stability. Some people are making the RC and the real ones exceptionally narrow ( i.e Genuine Risk, Skandia.) The one Im building (still havent firmly decided on canting keel versus moveable ballast) is wider than these other ones so it can carry a bigger rig and plane while sailing wider angles downwind. If you get the hull shape and rig almost the perfect ratios, the canting keeler will still be able to destroy conventional boat on a course as you described. Upwind, with the larger rig, it may have a slight edge( that is really based on the skill of the skipper), reaching, it will walk away from the conventional one, and downwind, if designed to handle downwind conditions, it will also kill the conventional boat. If anyone ever figures out how to put a Code Zero type sail on a lightweight CBTF boat, in 3 knots of breeze it could possibly be doing 5 while beam reaching.
when i said gybeing back and forth above, i forgot to specify that they sail MUCH wider angles than the conventional keel boats.
mmm, i have already figured out a way to have a assymetrical kite (this includes having a bow sprit, which will be pretty big) on mine, but i need a locking device for the halyard & everything, then i need to work out how to do the sheets, i have sort of worked it out, its gonna take a hell of a lot of room up on the boat though. ohh & you talk about taking like 400gms off your keel, my dads boat weighs either 7 or 9kg (have forgotten) , mine weighs about 3kg, the keel is 1kg
I see said the blind man to the crippled nudist who put his hands in his pockets & promptly walked away.
USA2,
Did you ask some questions a while back on SA? I think I answered you (as did several others). I think one of those replies might have led you here? Anyway, welcome to our little group. You got some good advice over on SA and made some good contacts that can help you. There is a lot of help here as well. Try searching through the archives. There is a lot of good stuff in there. Much of it gets bogged down in mud slinging but there are some real gems if you are willing to dig.
But the best thing to do is to ask. There are several boats sailing already built by the people participating in this thread. We have worked out a lot of issues already and everyone here would love to share with you what we have learned.
Will Gorgen
ya, i was on SA a while back.
The main thing Im wondering about for the RC canting keel models is the thru-hull fitting. I havent figured out how to seal where the keel comes trhough. Also, I think the model Im building now will be just as fast as a canting keeler because the beam allows the on-deck weight to go way out to weather, therefore creating a powerful righting force.
On my canting mast boat, the rudder cants with the mast (the keel is not allowed to cant, but you can cant the mast and the rudder).
An idea I plan to use to seal it is to use a baby bottle nipple. The base of the nipple can be glued to the floor and then the rudder shaft can stick up through the tip of the nipple and be sealed there. The nipple will “flood” but will be sealed at both ends so it will not flood the boat. I actually found some miniature gaskets that look like bably bottle nipples at tower hobby.
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LX9155&P=
All the hinge mechanism would be contained inside the sealed flooded area, so you will have to use bearings that can tolerate being wet. For my rudder, I am using a simple teflon bearing for the hinge.
Will Gorgen
USA2
The sealing part of the keel mechaism is the easy part what you needs is a ahsft running fore and aft in the boat that the keel come up into the the shaftthen goes through a seal and then a lever attaches to the shaft on the other side of the seal.
This seems to be the most efective way of doing it as i have tryed a boot system but this provves to be affective for only a while and then the boot perishes a bit and splits and leak.
Any way if you want and help give me a bell
Cheers
Here are some PDF’s of my keel arrangement.
Download Attachment: [ Keel arrangement.zip](http://www.rcsailing.net/forum1/data/JohnB/200522204933_Keel arrangement.zip)
31.58KB