Greetings, thank you guys for you kind words. The rudder was cut on my friend's CNC machine some 2-3 years ago.
Now, following your advice I've designed new cam arms. This is the left side arm, green circles represents movement of the centering bearing- 15º to each side.
Thursday I'll cut a prototype out of some aluminum sheet, and if that works ok, I'll order lasercut version out of 3mm steel.

http://SimHQ.com/forum/tmp/11498.jpg

Attached Files newcam.JPG