Robot Servo With Idle Horn

The purpose of this instructable is to provide a “shell” that can be used to convert a common servo motor to a robot servo with an idle horn. The idle horn (opposite the main drive horn) spins and allows easy connection of a C joint. When I built Santa’s Shop, I had 32 robot servo motors (with an idle horn opposite the main horn) in the animatronic figures and they had to operate 4 hours per day for about 35 days. Two of them failed during the season, while there were no failures in my creations using cheapo servos. For this project, I used my “shell” on three servo motors and built an arm.”

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