Hello everyone,
I´m 6 years into the build of a legacy -12 (rotax ULS) and I´m currently installing the Dynon autopilot servos (Dynon AP SV32. Section 44A). After installing the one on the back for roll/ailerons I noticed a slight resistance/friction appeared when moving the control column side to side (ailerons). I tried moving by hand the other AP servo arm, the one I was going to install for the elevator control, and it had the same kind of small steps friction/resistance as what I was feeling on the ailerons.
I proceded to install the elevator servo, and there it was! I could now also feel that same friction/resistance when moving the elevator. I seems this added friction is due to the electric motor of the servos but I wanted to make sure with anyone else that has already installed this servos to make sure they had the same "issue". The friction is very small, you can still move the control column with a very slight pressure but it´s a pity because before it had barely any friction at all.
Also, I had to change the AN3-7A for a AN3-10Aon the servo arm of the elevator as if I used the called-for -7A It ended up being slightly short and I didn´t get the 3 threads sticking out of the nut. Anyone else had this issue? On the push-rod to roll servo installation, instructions call for using a longer AN3-10 length for a very similar set-up (it has 1 more washer to hold).
Another issue/thing I noticed on this section:
The nut that holds the elevator/pitch servo arm to the push rod is a AN365-1032, an elastic stop nut. Has anyone tried using a longer drilled bolt and a castellated nut?
I´m asking because I just read the post from 4Kilo titled " Check Your Autopilot Servo Arm Screws!" and I tested to see what would happen if that elastic stop nut gave away. What happens is the push-rod falls down under the servo when using the elevator in its max up position and then it locks there as it is pressed against the bulkhead under the seats, creating quite a problem because the locked pushrod stops you from moving the elevator past that position. Is this really an issue or is the elastic stop nut reliable enough for such a critical set-up? I tried doing the same thing on the roll servo but over there it seems the push rod doesn´t get locked anywhere if they become loose from any one side.
I think the Dynon servo has an over-torque protection that releases the servo arm if it becomes stuck but that won´t prevent the push-rod from locking the control column if it has become loose from the servo arm and is still attached to the control column.
Or am I worrying too much??
I´m 6 years into the build of a legacy -12 (rotax ULS) and I´m currently installing the Dynon autopilot servos (Dynon AP SV32. Section 44A). After installing the one on the back for roll/ailerons I noticed a slight resistance/friction appeared when moving the control column side to side (ailerons). I tried moving by hand the other AP servo arm, the one I was going to install for the elevator control, and it had the same kind of small steps friction/resistance as what I was feeling on the ailerons.
I proceded to install the elevator servo, and there it was! I could now also feel that same friction/resistance when moving the elevator. I seems this added friction is due to the electric motor of the servos but I wanted to make sure with anyone else that has already installed this servos to make sure they had the same "issue". The friction is very small, you can still move the control column with a very slight pressure but it´s a pity because before it had barely any friction at all.
Also, I had to change the AN3-7A for a AN3-10Aon the servo arm of the elevator as if I used the called-for -7A It ended up being slightly short and I didn´t get the 3 threads sticking out of the nut. Anyone else had this issue? On the push-rod to roll servo installation, instructions call for using a longer AN3-10 length for a very similar set-up (it has 1 more washer to hold).
Another issue/thing I noticed on this section:
The nut that holds the elevator/pitch servo arm to the push rod is a AN365-1032, an elastic stop nut. Has anyone tried using a longer drilled bolt and a castellated nut?
I´m asking because I just read the post from 4Kilo titled " Check Your Autopilot Servo Arm Screws!" and I tested to see what would happen if that elastic stop nut gave away. What happens is the push-rod falls down under the servo when using the elevator in its max up position and then it locks there as it is pressed against the bulkhead under the seats, creating quite a problem because the locked pushrod stops you from moving the elevator past that position. Is this really an issue or is the elastic stop nut reliable enough for such a critical set-up? I tried doing the same thing on the roll servo but over there it seems the push rod doesn´t get locked anywhere if they become loose from any one side.
I think the Dynon servo has an over-torque protection that releases the servo arm if it becomes stuck but that won´t prevent the push-rod from locking the control column if it has become loose from the servo arm and is still attached to the control column.
Or am I worrying too much??