Build two simple light strong rudderboxes for the Viola 14 sailing canoe and sailboats

viola sailing canoe 14ft 75lbs performance singlehanded sailing dinghy plan - storer boat plans

Simpler method of making a rudder setup for sailboats including the Viola 14 canoe is a direct descendant of our original dagger rudderbox carrying on the light but strong and easy to build construction. This article is a resource for sailing canoe and outrigger canoe rudder builders.

Other boats are better off with the dagger rudder for the reasons below.

This section is built around text and images by Joost Engelen about setting up the Viola swing rudder and the design simplifications we worked out.

But overview and discussion between the two types is by Michael Storer.

Viola Sailing Canoe info

More Rigging  Details for the Viola 14 Canoe

So why a different rudder setup for a sailing canoe when the dagger system is usually far superior?

On all of our sailing dinghy designs we use a dagger rudder setup with a bungee/shockcord loaded open back.

Shockcord rudder retainer - three wraps of 6mm shockcord please!

Apart from older designs from the Northern Hemisphere we seldom see swinging rudders on Australian raceboats.

Epoxy has low clamping pressure – so tape is enough.

Building the Simplest and most effective rudder and tiller

They use a dagger system with the blade sliding up and down. Either with an open back or a closed back

Get a PLAN – Bolt placement is CRITICAL and some important contstruction tricks – get it wrong and it will break. Get it right and it will have a very long service life. – the best way to get the design (and details on making spars, super accurate foils, scarfs, butt straps, even sail making) is buy buying the $36 Oz Goose Plan.

The advantages are several.

  • Light
  • Simple to make
  • Strong and very reliable as long as you put in the required bolts
  • Yes … read the above point again. Don’t forget the designed bolts or it will break very quickly
  • Steering loads go from tiller to rudderblade directly
  • Nice accurate light steering in any water depth. Unlike a swinging blade where a little kickback gives almost no reduction in draft but creates very high tiller loads and the risk of breaking the box.
  • Low loads at speed where a swinging blade at speed it can kick back a little producing very hard to deal with tiller forces.
  • Handles hitting the bottom – if the blade grounds out it will swing backwards and once over the obstruction will pop back down again.

The big win is very light and positive steering in any depth of water.

Once used it makes so much sense from a practical and construction point of view it is clear why we seldom see swinging rudderblades in the antipodes.

However … with this type of rudder setup, it needs to be pushed down manually. Moving to the back of a skinny light sailing canoe can be tricky. So it is a good idea to have a swinging canoe rudder blade blade and design out as many drawbacks as possible.

There are some important parts of the detail to make it strong.

If it breaks it is your fault for not building it right.

These are non obvious involving the bolt through the tiller and the ply or glass around the end of the tiller to prevent splitting.

The cheapest way to get the most up to date plan for  the dagger  rudder is to buy the Oz Goose plan for  $36.

Buy Oz Goose Plans

Where the Dagger Rudder with kickback came from – Paper Tiger Catamarans circa 1973

I don’t want to claim this as my own work. Like most of my good stuff, it is stolen.

But I am a careful student of excellence that actually works.

In this case, Jay Booth (father of well known International sailor Mitch Booth) took me along to see my first big Catamaran regatta. Saw Paper Tigers for the first time. They are probably the quickest non-trapeze 14ft cats. Very light – 50kg platform (110lbs) plywood or foam/glass.

Ron Given, the designer had come up with the same dagger and kickback rudder setup. As a 13 year old, I mentally went “wow” and filed it away. My first and second boats had swinging rudders and I could see the advantages of the Paper Tiger System.

When I moved up into NS14s I started making and breaking dagger rudder boxes. It took me a few seasons of making rudderboxes this way to get it right. I broke a lot of them before I realised the placement of the bolts was critical. After that – very reliable.

The one flaw of the dagger rudder system – narrow boats.

In many sailing canoes, the stern is quite narrow so it is hard to go to the back of the boat to manually push the canoe rudder blade down. Wobbles and potential or real capsize!

So with the Viola 14 Sailing Canoe, we needed something that worked well but had the maximum simplicity and minimum weight.

The bad way – poor structural efficiency of a normal swinging rudder leads to heavy and complex construction.

So what were the problems with the usual swinging rudder setup?

… Or What are the funny shaped green bits for?

  1. Conventionally the tiller is at the top and the pivot for the rudderblade is at the bottom. This means the torque from turning the tiller has to be transmitted from the top to the bottom by the rudder box.
  2. The spacer is fiddly to get right and prevents full vertical retraction of the blade
  3. If spacer is omitted the cheeks have to be  very thick.
swinging rudder box design for sailing canoe - the old heavy method.

In comparison the dagger system has two faces of 5mm ply and a single spacer 25 thick running up the front edge. No special shaping and all the components can be light because the rudderbox is very lightly loaded. Even if it hits something the blade is free to move backwards.

So as the principle  of the dagger rudder setup is that the tiller turned the blade directly – the box was not carrying any turning loads – then we had to do the same for the swinging canoe rudder.

So the pivot for the swinging rudder moved up to be controlled directly by the tiller. This took the load off the rudderbox.

The internal spacer between the cheeks to be a simple rectangular piece of timber like our drop in boxes saving weight and general messing around with complicated and heavy bits. And the rudder cheeks could be thin like the hull ply. But note that like the dagger rudderbox, the bolts in the structure do important work.

Holding a swinging canoe rudder down – the ways that work and the ways that don’t

If you boat is very slow it is possible to get away with a weighted swinging rudder – even if you choose to ignore Uffa Fox (the father of the planing dinghy some say). That “weight only belongs in Steam Rollers”.

Remember that sailing canoes were the fastest human made means of transport for quite a few decades. So your canoe or  outrigger canoe will hit serious  speeds at times and you don’t want the rudder coming up a bit on you.

The problem is that even if the boat is a little faster than slow :) the rudder will creep up a little and the tiller loading becomes very high just as you need the best control possible. Not a good thing.

Same if you use bungee to restrict the swinging blade – can’t get the bungee far enough away from the pivot to be useful. And then a bit more speed again up pops the canoe rudder. High tiller loads, veer, splash. Or  rudderbox breaks.

It took me a while to understand this too and it led to more than a few capsizes in the Lightweight Sharpies I was sailing at the time. They inherited the swinging rudders from the 12sq metre sharpie class they were derived from.

Rudder design to keep grip at speed

When the rudder lets go or takes control because the blade has rotated back – this is what happens on a very fast 20ft light dinghy.

In the old days we used stainless steel wire to hold the swinging rudders down totally positively on fast boats. Happily we can now use spectra rope and avoid the steel spikes that rip your skin open like a scalpel after a half season of use.

We often used a relatively weak cheap cleat that would break if we hit anything hard.

Rudder pivot for the Viola 14 Sailing Canoe rudderbox

The rudder downhaul is necessary to keep the foil down. The uphaul is optional; not really necessary when just using the boat for sailing since the foil will float up nicely (after all it is all timber with some glass!), but necessary for when using the boat for cruising and having to paddle (when paddling hard the rudder will start to steer the boat which is annoying).

Insert the swinging rudder blade in the rudder stock so that the holes in the rudder stock and the hole in the foil taking the bolt line up. Insert the bolt and put the nuts on. Use big washers on the outside of the bolt to distribute the forces over a larger surface.

Do not overtighten the nuts on the bolt, just tighten them up by hand. Too tight and your swinging rudder won’t swing! If using 2 nuts on each end, one can tighten these against each other using spanners and this will avoid them coming loose. Use cap nuts, or better Nyloc nuts on the outside to avoid having any sharp bits. If using Nylocs you don’t  need a lock bolt

If you can get a bolt with a plain shaft then do so.

6mm bolt

Downhaul for the Viola 14 Rudderbox

The downhaul ends up in a clam cleat. One could use a auto release clam cleat if afraid for hitting something with the canoerudder unexpectedly (SD-002570 Auto-Release Cleat). The rudder is not very deep though, but make your choice in accordance with your specific needs.

A cheaper way is to use a cleat that will break or slip if you hit something hard. We used to use something like this in a fairly small size to go with the 3mm rope we used.

In the photos the downhaul consists of a 3mm rope with Dyneema core pre-lead line and a regular polyester 4mm control line that stretches. Due to the stretch in the downhaul control line it is easier to tension the downhaul and to get it out of the cleat again.

To obtain the correct position for the hole in the swinging rudder blade for the downhaul attachment, rotate the board in the cassette until the leading edge of the rudder passes the aft bottom corner of the rudder cassette.

Mark this place and drill the hole just below this mark to ensure that the downhaul attachment point will clear the rudder box when the rudder rotates in its case.

Obviously you will need to drill the hole 20mm or so back from the leading edge.

It would be wise making an epoxy bushing for the downhaul attachment hole which is very simple to make as follows:

  1. drill the hole oversize first,
  2. fill the hole with epoxy glue using packaging tape on the other side and,
  3. only then (when the glue has hardened) drill the final 4mm hole necessary for the 3mm pre-lead line. This avoids any potential water ingress.

Rudder Uphaul for the Viola Sailing Canoe Swinging Rudderbox

The rudder uphaul is very important for paddling the canoe. If the canoe rudder drags in the water then steering with the paddle doesn’t work very well as the boat will slowly turn left or right. Or the nose will blow away from a cross wind.

The rudder uphaul is a very simple affair on the Viola 14 canoe.

A hole is drilled in the rudder head aft of the centreline of the foil and a rope is attached to this hole by a simple knot on the opposite side of the where the clam cleat for the uphaul is located (please refer to the first photo of the Viola canoe rudder setup and its controls above for the exact location of the hole in the rudder head).

Obviously, the same comments apply in respect of making an epoxy bushing for the uphaul attachment hole.

The rudder uphaul runs directly to the clam cleat. Very simple and it works great.

A 900mm long tiller extension is suggested mounted right at the front of the tiller.

All our sailboats have these types of rudderbox for ease of building and pure useful function.

Our Plans are really well thought through.

See our Storer Boat plans on the home page