This 2:1 Ratio, SG12 Series Servo Gearbox utilizes the goBILDA 2000-0025-0002 servo that has been programmed by the goBILDA servo programmer for continuous rotation. This means that the servo driving the gearbox has no limitation to the amount of travel. The signal that you send to the servo will determine the speed that the servo rotates. It is bidirectional and fully proportional, meaning that you can vary the speed and direction with the signal being sent from your servo controller. This 2:1 ratio model will result in the large aluminum gear spinning at half the speed of the original servo, but with twice the torque! If the SG12-20-CR doesn't suit your needs, be sure to check out the other Servo Gearbox options.
The 1/2" diameter stainless steel shaft of the Servo Gearbox is supported by a pair of 1/2" ball bearings and held in place with retaining rings above and below the bearings so that it can withstand loads from any direction. An arm, disk or linkage can be fastened to the threaded holes on the Actobotics 0.77" pattern. Alternately, the 0.14" thru-holes on the perimeter of the aluminum hub gear can be used to fasten standoffs, spacers or a linkage to, or, you can slide a 1" clamping hub around the spacer on top of the gearbox for quick adjustments to the item being fastened.
The Servo Gearbox is easily attached to Actobotics Channel, given it's overall width of 1.32" (to match the internal width of U-Channel). For those of you installing in an R/C vehicle, the 585506 bracket is a popular choice as it creates ears to mount the servo gearbox down to a flat surface.
While this model is programmed for continuous rotation, you can actually toggle back and forth between continuous (open loop) and feedback (closed loop) mode, using the goBILDA servo programmer. When programmed to feedback mode, the amount of rotation will be 321 degrees and speed will be 0.32 sec/60°.
While we offer a variety of pre-made ratios, if you already own one of our Servo Gearboxes and want to change the ratio, here are the gears you will need to obtain the ratio you desire.
|Ratio||Servo Gear||Hub-Mount Gear|
|2:1||32T (615310)||64T (615194)|
|3:1||24T (615306)||72T (615198)|
|3.8:1||20T (615302)||76T (615202)|
|5:1||16T (615298)||80T (615206)|
|7:1||12T (615294)||84T (615210)|
|Weight||6.9 oz (196g)|
|Voltage Range||4.8V - 7.4V|
|No-Load Speed (4.8V)||20 RPM|
|No-Load Speed (6.0V)||25 RPM|
|No-Load Speed (7.4V)||31 RPM|
|Stall Torque (4.8V)||480 oz-in (34.6 kg.cm )|
|Stall Torque (6.0V)||600 oz-in (43.2 kg.cm)|
|Stall Torque (7.4V)||700 oz-in (50.4 kg.cm)|
|No-Load Current (4.8V)||150mA|
|No-Load Current (6.0V)||160mA|
|No-Load Current (7.4V)||200mA|
|Stall Current (4.8V)||2,000mA|
|Stall Current (6.0V)||2,500mA|
|Stall Current (7.4V)||3,000mA|
|Max PWM Range||900-2100μsec|