RE: 87" Yak Rudder hinge pins broke
Shawn,
Mine was a push pull single servo surface. It doesn't get much simpler than that. Arrangement was 1-1/8@servo to 1-3/8@horn with no radical angles. Surface mounted ball links on SWB arms with true RCL-70 linkage at the rudder horn. No binds or side loads anywhere. Never could get rid of the issue, and same as yours, could smack the surface to quiet the servo down. Not a good thing.
I've got an e-mail from another user that sent ten 8611's in for repair after well less than a year of use. Too much slop in the gear trains was the reason for sending them in. They tried to charge him about $35.00 apiece to repair the gear trains since the wear was part of "normal wear" and not warranty covered. After an animated conversation that noted there were far less than 100 flights on the servos they relented and took care of it, but that was enough to shake the customers confidence in the warranty coverage. He sold them all when they were returned and changed manufacturers.