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Pitch Servo - Control Arm Travel


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Question on the pitch servo control arm travel distance.  Installed the bracket to the bottom of stick and connected rod to servo, adjusted rod ends so the control travel is centered to servo swing, when stick is swung through all the possible travel areas things looks decent, but am noticing at extreme location fore & aft stick if I really force the stick into what are max travels (like heavy loaded stick and deflecting things to force every bit of movement in system), the servo arm is contacting the travel stop limit bracket. 

Does not appear to be a bad situation, however in my mind I sort of expected to see a tick more gap on the extreme ends, and arm never contacting these stops?  As I fabricated the stick bracket from scaling the FD drawing, I could be off a bit and would like to know what is the normal situation for servo arm travel?  I may need to make a new bracket and reduce span of hole.

 

image.png.76611f6ac9ede55c7f642d231bc34a70.png

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Here's a clip of cycling the stick fore & aft, this is going through full travel with lighter stick pressure, and probably is what I'd say is normal full travel envelope.  You'll notice the stick aft / servo arm forward has a few sheets of paper for clearance to stop.  Stick forward maybe a mm or so gap.  If I really lean on the stick and distort every bit of movement the arm contacts the stops in what I'm calling a kiss, not hard interference.  I think this is probably a good set up, a runaway servo would have travel limited by the stop right at same point of the airframe controls? 

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That should be okay. Make sure that you ball joints can swivel when at the extreme throws. Sometimes they will bind on the servo arm. Also I like a large area washer under the head of the bolt, in case the bearing would become separated from the rod end. It will keep the rod from becoming completely loose and getting somewhere it shouldn't. 

There was an AD on your Cessna 150 for the throttle linkage for the same issue.

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29 minutes ago, Tom Baker said:

Also I like a large area washer under the head of the bolt

Yup - they came with the Dynon generic servo mount kit I purchased, (the kit was an inexpensive option with AN hardware, rod ends, and such for $25).  I was a bit surprised the FD drawings didn't specify them, will include these in the final install.  Thanks much for the cross check on this.

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