Linear 25, 1/4-20 Thread, Std CR Servo

Here is another redneck linear with a little more power. Uses standard continuous rotation Servo, 1/4-20 all thread and has bearings on the spool. Should have many applications in robotics and home automation.
This linear has a one to one gear ratio and has travel of .050 inches per servo rotation. That give a travel of about 2.7 inches per minute with the Pololu 1248 (SpringRC SM-S4303R, Jameco 2128201 $13.95) continuous rotation servo. I do not have one, so have not tried it but, Parallax makes a high speed CR servo that is way faster (180 RPM), that would make the linear travel 9" per minute (Parallax 900-00008).
This design uses standard 1/4-20 nuts inside the spool to move the all thread rod. Uses two 18x12x4mm RC car/truck bearings on the spool. Yoke holds the rod fixed with a 1/4-20 nut, the gear and motor move the all threaded rod. Uses #4 sheet metal screws for fasteners and #6 machine screws for yoke pins.
Since continuous rotation servos work on speed and time this ty