Under-the-hull rudder. Let's call it a surf ski - even though it isn't quite.

Flat bottom with pronounced vee going back to said rudder.

The rudder looks to be the right shape, and I've padded it up with foam tape so
that it's right against the hull when straight ahead... but once it turns, the
vee causes a gap to open up.

In ocean waves, it absolutely has to have a rudder - but there's no weed
problem... so no workaround is needed for ocean paddling.

Fresh water is where I'm having the weed problem. Didn't have it earlier
in the season, but now there's this long thin weed growing that the
rudder catches quite nicely.

On flat fresh water, technically the boat can be paddled with the rudder
completely removed - but it's really, *really* squirrely and I don't think
I'd want to get caught in a wind squall that way.

Options I can think of:
-------------------------------------------------------------------------------
- Disconnect the rudder cables and duct-tape the rudder's leading edge to the
hull - making it into a skeg - and find out if the shape is really right
for shedding weeds.

- Concoct some sort of skeg to replace the rudder... but how to attach it?

- FIt a spoiler on the hull to lift (actually sink...) the weeds enough
so they don't get caught in the rudder/hull gap.

- Remove rudder completely and hang some sort of lee board back there - probably
made from an old windsurfer weed fin.
-------------------------------------------------------------------------------

Is there any conventional wisdom on this? I'd think surf ski users would have
the most pressing problems in this area.

--
PeteCresswell

(PeteCresswell) wrote:

- FIt a spoiler on the hull to lift (actually sink...) the weeds enough
so they don't get caught in the rudder/hull gap.

I can't say I've got a solution, but this sounds like a skeg/rudder arrangement
that's used on some sailboats. Basically, the rudder forms the back end of a
skeg - the front half is fixed.

This won't work with your rudder if it is a balanced design. That is, if the
rudder post is not exactly on the leading edge of the rudder, the portion of the
rudder forward of the post will swing free of the skeg part and catch weeds anyway.

To get the weeds to clear on the fixed part, there's going to have to be some
sort of sweep angle down that won't catch the weeds. If you build up a skeg
with a shallow angle relative to the keel, the size might end up being so great
that you will end up with a kayak that leecocks - a situation that you don't want.

Mike

Per Michael Daly:
To get the weeds to clear on the fixed part, there's going to have to be some
sort of sweep angle down that won't catch the weeds.

I think I've got that already. It's just the gap between the front of the
rudder and the bottom of the hull that opens up when the rudder is turned -
courtesy of the hull's vee.

Never thought about the post-as-leading-edge thing with something fixed/angled
in front of it. That seems like the Good-Right-And-Holy path to me....and if I
were ordering this kayak again, I'd ask for a little thruster fin box to be
installed there and have a rudder made as described...
--
PeteCresswell

Perhaps consider a reshaped rudder that would have more of a rake or
angle to it that might shed weeds. The reshaped rudder might be less
effective, but then you might not need a powerful rudder in fresh water,
just something to make the boat more stable.

You could take some plywood and try different rudder shapes to see which
gather weeds.

That assumes that you have reasonable access to the rudder to change
rudders and try different things.

I like the skeg idea, but that would probably require modifying the
boat. But maybe the skeg could attach to the same hardware that mounts
the rudder..... Turn the boat upside down, remove the rudder, replace
it with a "weedless" skeg design. Again the assumption is that you have
less need for rudder in fresh water.

By the way, the fishing crowd haul hooks through weeds all the time.
They have special "weedless" lures, you might want to look at them for
ideas.

Richard



(PeteCresswell) wrote:

Under-the-hull rudder. Let's call it a surf ski - even though it isn't quite.

Flat bottom with pronounced vee going back to said rudder.

The rudder looks to be the right shape, and I've padded it up with foam tape so
that it's right against the hull when straight ahead... but once it turns, the
vee causes a gap to open up.

In ocean waves, it absolutely has to have a rudder - but there's no weed
problem... so no workaround is needed for ocean paddling.

Fresh water is where I'm having the weed problem. Didn't have it earlier
in the season, but now there's this long thin weed growing that the
rudder catches quite nicely.

On flat fresh water, technically the boat can be paddled with the rudder
completely removed - but it's really, *really* squirrely and I don't think
I'd want to get caught in a wind squall that way.

Options I can think of:
-------------------------------------------------------------------------------
- Disconnect the rudder cables and duct-tape the rudder's leading edge to the
hull - making it into a skeg - and find out if the shape is really right
for shedding weeds.

- Concoct some sort of skeg to replace the rudder... but how to attach it?

- FIt a spoiler on the hull to lift (actually sink...) the weeds enough
so they don't get caught in the rudder/hull gap.

- Remove rudder completely and hang some sort of lee board back there - probably
made from an old windsurfer weed fin.
-------------------------------------------------------------------------------

Is there any conventional wisdom on this? I'd think surf ski users would have
the most pressing problems in this area.



--
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