canting keel

I am interested in making a canting keel for my one meter and am wondering how others have rigged up their keels, specifically how people controlled the swinging of the keel. My idea was to use have a multi block system on each side of the keel inside of the boat attached to a sail servo. If there are any other better ideas i would be interested in hearing them them.


I think if you do a search on “canting Keels” you will overload with information.

Vancouver Island

This is how I did mine, its a smaller boat but I used a cheap sailwinch to do the job. Basically what you have to do is calculate the load at the top of the leaver in the boat and then find a winch that can take the dont want to use a purchase system if you can, you want to be able to move the keel in a hurry.

Some of the guys have done geared systems on F100s that have worked very well.

Luff 'em & leave 'em.

With regards to Canting the keel on a One metre you will find that there is a lot more load than you think on the lever inside the boat and a sail arm will not do the job. I used a Sail winch in my first set up with a 2:1 but this does make the canting slow and the other problem is that the tension on the lines change as the lever moves in an arc and you can get the lines falling off the drum if they get to slack.

I have gone to a geared bulkhead and a sail winch running along it with a gear on the spine that has exactly the right turns to go hard over to hard over and give between 45-50 degrees of cant for the keel.

I would run some serious numbers before attempting it as it can be a gear breaker and you do need some serious battery power to run it as the drain is quite high as the winch is always loaded.

The other issue is a sealing system and this requires some work with an off set shaft and seals and so forth.

Anyway hope it helps

Cheers Gappy


This is an ambitious undertaking. There are several things to consider. Servo strength is one very important one. Sealing the mechanism (making it water tight so your boat does not sink) is another. Battery life is another. Lateral resistance is another. Class legalness is yet another.

The last question first: The only one meter class where canting keels are legal is the F100 class. Are you planning on making an F100? If not, you are probably not planning on racing your boat and one cannot help but wonder why you want to bother with such a technical challenge as a canting keel?

Your choice of lateral resistance is also very important. When you swing your keel to windward, it will no longer be able to keep the boat from going sideways in the water. So you are going to need some other appendage to help this situation. There are several chices available. The best know option is twin rudders (one forward and one aft), but others have been quite successful with a daggerboard forward of the keel (take a look at the Ultimate Warrior built by Wind Warrior yachts in NZ: ). Another option is the kFoil system that Doug Developed earlier this year (do a search in this forum for kFoil to see some pictures of this idea).

There are several ways to develop a sealed mechanism for your canter. I won’t go into details here, but if this is an area you are struggling with, let us know and there will be lots of ideas posted, I’m sure.

The mechanism for the swinging of the keel (your original question) will effect a lot of how the system performs. If you “hold” your keel to the side by constantly applying holding torque with your servo, you will be eating up your battery power on a constant basis. This may be fine for pleasure sailing, but results in a very undesirable situation if you plan on racing as you will either need to carry a lot of battery power (lots of weight) or need to replace it fairly often (which can cause problems during a regatta).

My solution is to incorporate a locking off mechanism that allows the servo to hold the keel to one side without any torque being applied.

Actually, I need to be more specific. I am building a canting MAST system, but if you turn this diagram upside down you could see how the same mechanism could be used for a canting keel. I chose to cant the mast instead of the keel because this is legal to do in the US1M class. I intend to race my boat (someday) and so I wanted to make a class legal boat.

Anyway, back to the mechanism. Here is a sketch of the system:

Download Attachment: cantingmast.gif

You can see that at the two ends of the servo travel, there is notorque loading into the servo. So the servo can hold the mast in that position without consuming any battery power.

The difficulty with this mechanism is that the servo is required to swing through about 270 degrees to cause the mast to swing through 100 degrees (50 degrees to either side). Most servos are limited to 180 degrees or less. So I have rigged up a system that uses a HiTec 725 (sail winch servo which has 3 revolutions of travel) and a 4:1 gearbox that reduces the servo travel to 270 degrees while at the same time increasing the torque by a factor of 4.

Her is a picture of how it looks. This picture was taken during a fit check so the blue masking tape is holding the mechansim in place temporarily. The mechanism will be affixed permanently to the keel box and bulkhead system before the boat is finished:

Download Attachment: P5170032.JPG

You can see the brass tube slider on the mast butt. The white arm is the canting arm which is attached to the output side of the gearbox. The gearbox and servo are on the other side of the bulkhead and cannot be seen. The mast pivot is just below the top of the compression vang (and on the forward side of the mast).

By the way, I have an Excel speadsheet where I calculate the canting mechanism forces and torques required. As gappy suggests, you should take a serious look at these numbers as you design your system. There are a lot of forces in play here and quantifying them is the first step in dealing with them

Hope these ideas help you in your design.

  • Will

Will Gorgen

To emphasize one point made in Will’s post, there is currently no group in the US racing canting keel boats and no recognized racing monohull class in the US that even permits their use. Even the “F100 Class” mentioned is still a concept originated by a few sailors in France that hasn’t yet established racing fleets anywhere else in the world.

However, for a concept to play around with, Will’s post is a very good starting point. No one has yet figured out optimum shapes and placements for the foils on an r/c canting keel boat so the field is wide open for experiment.