Dynon AP Pitch Servo Installation

[BJohnson]

I am beginning the installation of the Dynon Autopilot Servo installation and have run into an issue. The aluminum tube between the bellcrank and the servo arm is at an angle that the tube contacts the bellcrank without being close to the servo arm. See the attached photo

Do i need to change the length of the spacers, or shim out the rod end bearing with washers? Changing the spacers will place the bellcrank offcenter from the pushrod passthrough hole in the bulkhead.

I emailed dynonsupport but it being the holiday and all, thought that there others online that might have resolved this already.

 

[MNForrest]

Switch the rod?

If you move the rod to the other side of the control horn, will that do the trick?

ff

 

[Jamie]

I had the same issue.

Just space it off with AN960 and AN690-L washers. Don't add too many washers though, it will increase the leverage on the bellcrank causing it to twist which equals slop in the system.

Edit: You need to space it off on both ends of the pushrod.

 

[Greg Arehart]

Guess I better look at mine again. I did not have any interference issues that I recall. Another option would be to lengthen (i.e., cut a new) the Al connecting rod so that you don't have to use the jam nut. Just be sure that the connecting rod can IN NO WAY come off the rod end bearing (recall a recent post on this forum where this arm came loose and jammed, rendering elevator control difficult).

greg

 

[BJohnson]

Moved the rod to the other side

I moved the rod to the other side and the angle is a little better, and even though it does not look like it, the jam nut does not drag on the bellcrank as it moves through the range of motion. But this is not how the documentation shows it.....

I'll try the extra washers next.

 

[Camillo]

I opened my installation kit just today and noticed that rods are different lenghts. Maybe you already did it, but I would try to put the longest rod on the bellcrank side of the aluminium tube.

If not enough, I would try a smaller nut.
If not enough, I would try washers.
Maybe I would also try to make a couple of more turns in that rod and prevent nuts from unscrewing tying a tie wrap per side, just behind each nut. I plan to do this also on all pushrods nuts. I think this will prevent the tube to move slightly toward one direction (i.e.: screwing on one rod and unscrewing the other).
But, I don't like the idea of putting the rod on the other side of the bellcrank; it doesn't seem to work straight.

Camillo

 

[N941WR]

Brice,

Do not install the arm on the other side of the bellcrank, as you have it in your 2nd picture.

You can flip the push rod end for end, thus putting the longer rod end on the bell crank. This would move the jamb nut away from the bell crank. The other option is to turn the nut so a flat side is against the bell crank rather than a point.

There are some pictures of the install on my web site:
http://www.repucci.com/bill/dynon autopilot release.html