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Retractable rudder
By:Mark Bodnar
Date: 1/7/1999, 11:33 pm

Reading the discussion on skegs has rekindled my thinking about adding a rudder to my CLC Cheas 17. I really don't want the typical rudder sticking off the stern of my kayak.

I had thought about reproducing the small rudder used by Dagger on the Sitka kayak (the bottom 1/3 of the stern is a 'trim tab' that can swivel back and forth providing a small rudder effect)-but if the stern raises out of the water on a wave the rudder is useless.

Back to the drawing board. I was trying to think of a system that would have a retractable rudder.

Heres my most recent idea (see picture). The rudder would pivot up and down inside an enclosed box, the addition of a sleeve over the upper control arm would ensure it is water proof but still flexible enough to permit pivoting. With the rudder down - cables could turn to rudder. Retracting the rudder would require the bent upper arm (?) to be straight in line, therefore the rudder would not get jammed at an angle. Fully retracted the bent control arm would ensure that cable attachments are still above the water line, thereby minimizing risk of leakage. The rudder could be spring loaded (with a bungie) or have an open/close rope system (attached ~the bend in the arm, a rope pulling up could extend the rudder. Another rope from the cable T attachment pulled forward would retract the rudder --- still keeping everything ~watertight)

The only technicality I can think of at this time is how much space would be lost to the system. Clearly this involves some moving parts in the aft hatch that could not risk being blocked up by gear. It should fit well back in the aft hatch - taking up only a few feet of relatively narrow packing space (need to have enough room for the control arm to swing through a fairly good arc). Plus, I guess it may be difficult to find the appropriate pivot mechanism - an axle with the control arm going through the center could pivot while the control arm could rotate in its hole.

Since the entire rudder would be underwater, and in clean water (~no turbulence) a much smaller surface area should be sufficient - say ~6" long x4". With that size (leading to a 5" deep slot and therefore a 5" long upper control arm (above the bend) - a 6" internal boat width should allow almost a 60deg swing in either direction.

Any suggestions???

BTW, sorry if my thoughts are a little disorganized - I'm making this up as I go along.

Mark

Messages In This Thread

Retractable rudder
Mark Bodnar -- 1/7/1999, 11:33 pm
Re: Retractable rudder
Lee -- 1/9/1999, 8:34 pm
Re: Retractable rudder
Mark Bodnar -- 1/9/1999, 9:47 pm
Re: Retractable rudder
Lee -- 1/11/1999, 8:14 pm
Re: Retractable rudder
Nick Schade -- 1/8/1999, 9:52 am
Re: Retractable rudder - image repost
Mark Bodnar -- 1/8/1999, 9:24 pm
Re: Retractable rudder
Mark Bodnar -- 1/8/1999, 12:05 pm
Re: Retractable rudder
giles -- 1/8/1999, 1:52 am
Re: Retractable rudder
Mark Bodnar -- 1/8/1999, 12:09 pm
Re: Retractable rudder
giles -- 1/8/1999, 1:46 am
Re: Retractable rudder
Bob Hysen -- 1/8/1999, 1:21 pm
Re: Retractable rudder
Mark Bodnar -- 1/8/1999, 7:24 pm