Maybe I could do one that is retractable/ajustable while paddling. There is a lot of seaweed in the waters I move in. I think that it would do a better job than the rudder which is just used for not having the rear skating out to the sides. Making the rudder was struck by atleast two Lucky instances:
1) the attatchment-point on the deck is very solid but still able to swing the rudder up to let go of cought weed.
2) my last piece of thin plywood matched the rudder-shape. It has a front-edge that tilts 45 degree backwards into the water and thus will lift itself off big splotches of weed.
I stear the rudder with my big toes & my head - all the rest is by instinct. A fixed solution could be nice.