Summary

Mounts a standard Hitec servo with a servo horn and axle hub on a Tetrix channel, with the servo and axle hub aligned to a large Tetrix hole. This provides better support for the servo and protection against side shocks to the axle. It can also be used with the Tetrix Rack and Pinion set for driving the pinion gear with low loads.
Requires seven 6-32 x 0.75" screws.

Instructions

Print both pieces.
Insert 3 nuts into the nut holder circles on the servo-side piece. If these don't slide in easily, you can screw through the piece and tighten the screw to pull the nuts into their positions. Then loosen and remove the screws and the nuts should stay in place.
Attach the servo horn and axle hub to the servo. No horn screw is needed as the horn and hub will be securely sandwiched between the servo and the tetrix channel. Align the axle hub set screw with the top of the servo for later access. Optionally attach the axle now.
Attach the servo to the servo-side piece with four 6-32 x 0.75" screws and four nuts.
Sandwich the tetrix-side piece between the tetrix channel and the servo.
Fasten everything together by screwing three 6-32 x 0.75" screws through the channel, the tetrix-side piece, the servo-side piece, and into the three nuts previously mounted in the servo-side piece.
Optionally attach the top of the tetrix-side piece with two more short, standard tetrix screws and nuts.
If you didn't do it already, insert the axle and any associated bushings or set collars and tighten the set screw through the hole at the top.

Tetrix to Hitec Standard Servo Thru Mount - V8