The International Canoe

The (DC) rules state that the rudder must be capable of being raised or removed without the use of tools with the canoe floating upright.
Normal and sensible procedure is having a rudder that drops in from the top, and the rule seems to be written with that in mind.

I'm considering a rudder that goes in from the bottom, with a clip on tiller. As long as I can insert the shaft from the bottom I should be right rule wise?

If you dont require tools you would technically be ok.

Practically I would say getting a rudder in and out from below while afloat would be difficult in even a light breeze but not impossible. It would be near impossible with on shore waves and 15+ knots, even dropping the rudder in with a conventional IC system can be difficult. Having to get a rudder in from the bottom is something I wouldn't recommend doing with some breeze unless you get great deals from your mast supplier .

Im guessing your looking at putting foils on a rudder, been there done that wasted alot of money for no improvement (on an IC that is), although the DC could throw up some advantages for foils on the rudder in a blow.

H.

No, I'm not going down the winged rudder route. Reasons are quite simple:

1. New rudder will have rectangular stock, so I need to fit a sleeve around it as a bearing. This will be quite a bit thicker than what I have now, so the cassette will be bigger

2. Simpler and lighter construction of the boat, just bond in a tube rather than build a box

3. No scratching of the rudder when sliding it through the box

Downside is practical as you say. I'm quite clumsy with getting the rudder in as it is, I always put it in/remove it from outside the boat. So compared to that it won't be much difference, just a bit harder to find the hole from below. I'm still thinking, we'll see.

I thought about doing a similar thing but when I think about how diffcult it is to reach under the boat and get rid of weed off the rudder, the thought of trying to fit a rudder.... practically you would have to turn the boat on its side, fairly easy to launch, but recovery may be a little more diffcult, depends on where you sail. I have gone for a transom hung rudder, which I quite like, but many people think it looks ugly and has performance reducing properties, I find it works well.

Weed is an issue where I race, thanks for reminding me. Think I'll go conventional after all...

Have been looking at the galleries of pics in research mode. I noticed the hinged rudder boxes on the German boats. Could that not be used with a foiling rudder?

i've given this a fair bit of thought in the past. If one were to have a lifting foil on the rudder it would be an advantage to be able to get as close to the fore/aft COG as possible. Friction would be the big challenge if the whole rudder box were to move, and the sheer complexity of the installation if one were to have seprately moving horizontal surfaces is a bit intimidating...
In one of my wilder flights of fancies I mulled over the idea of having the last three feet of the stern pivoting with the rudder box, which given a two foot long rudder blade like a Moth would probably enable the lift point of the foil to be ahead of the aftmost position of the seat. At that point I got to the end of the bottle of amber Scots fluid, and decided that learning to sail the boat better might be a superior option...

THe pivot cartridge with a dagger style rudder makes a great deal of sense to me in restricted waters.

I have never vertured near a foiled boat and wont have the lift from a kite. If It could be built what benefits would it provide with a foil on the rudder but not the centreboard.

I am enjoying this its got my creative joices going. I found myself today doodling prospective paint jobs during a call with a client!

You'd think so, but you'll find in practice that the standard style of rudder is so short - knee deep in flat water - that the normal setup just isn't a problem...

There seems to be (to me) three styles of rudder currently used in the fleet,
the traditional slot in type, as Jim says does not normally pose problems with hitting the bottom as is very short, about 600mm long
the pivot type, that John and Colin developed that pivots through the back of the boat and
the conventional type that slots dagger style into a rudder stock off the back of the boat
they all work well, and to be honest I am not sure speed or ease of use differ much, personally I have a off the back style as I thought it was easier and lighter to make.
Foils on the rudder do not seem to make much differance, if you are conserned about nose diving then a sliding carrage that works well is the best thing, slide it back before you head off down wind and you should be fine.