Degrees of rudder movement

[ilbuildit]

   Does anyone know how much movement in degrees is optimum for the 16's rudder before it acts more like a braking device then turning?  Is there a spec from Com-pac on this? So basically how far can you push the rudder over from zero degrees before it doesn't turn the boat efficiently or at all anymore?

   Thanks in advance for anyones help! Lee...

[ilbuildit]

   One more point on this question. Does the foiled rudder change the optimum degrees of movement (For the better)?

   Thanks again. Lee...

[tsaiapex]

"Does anyone know how much movement in degrees is optimum for the 16's rudder before it acts more like a braking device then turning?  Is there a spec from Com-pac on this? So basically how far can you push the rudder over from zero degrees before it doesn't turn the boat efficiently or at all anymore?"

Lee, you are getting way too serious about optimizing this little sailboat.  Any movement on rudder creates braking force, this is how boat turns.  So to simply answering your question: turn the rudder as little as possible, use sail control and crew weight to induce the turn.

Jeff Tsai
CP19, Mary Grace
Apex, NC

[ilbuildit]

   It's not that I am looking for optimum performance out of this boat, it's that I am optimizing the rudder control from the helm that I built for my 16. (See "Project Sailboat" on www dot designsmithfabrications dot com) I don't have a tiller anymore and to get the correct geometry from the control input from the wheel linkage port/ starboard turning to get the most out of the degree of rudder movement before it starts to really oppose forward turning movement at it's worst.

   So if that makes sense, I still would like to know from other peoples opinion or general knowledge about rudder movement.

   Thanks again in advance. Lee...

[tsaiapex]

Lee,

Now I understand the background behind the question!  What an interesting project you have going on there.

I wonder if a call to Hunchins will be worth of your time.  Their experiences on Horizon cat with wheel option may shorten your design process. 

Good luck and have fun!

Jeff Tsai
CP19, Mary Grace
Apex, NC

[Craig Weis]

I do not have any idea about the angle of the dangle equalling the mass of the ass, but from the tiller or imaginary tiller, I do think that a visual siting from the stern will reveal a 'sight line' that when projected from a maximum turn [That would be the tiller hard over, till it can't go any further and runs into something] would give a pretty good idea of the number of degrees. You really don't use very much unless the boat is in a pickle at near zero speed and the captain is trying not to run into something.

My best guess would be about 120 deg sweep, lock to lock. With a tiller its a full 90 deg if one lifts the tiller to clear the combing.

If you wish to read about this rudder deg question I'd look at David Kerr's book 'The Nature of Boats'. skip.