

SpringRC SM-S4303R Continuous Rotation Servo
The SM-S4303R is a standard-sized servo that has been built by SpringRC specifically for continuous rotation, making it an easy way to get your robot moving. It features two ball bearings on the output shaft for reduced friction, and it offers easy access to the rest-point adjustment potentiometer. This is the strongest (and most popular) continuous rotation servo we carry.
Key specs at 6 V: 70 RPM (no-load), 67 oz-in (4.8 kg-cm), 44 g
July 9th Update: We expect to have this servo back in stock next week. For an immediately available alternative, please consider the Parallax continuous rotation servo.
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The SM-S4303R is a standard-sized servo that has been built by SpringRC specifically for continuous rotation (up to 70 RPM at 6 V), and it is the strongest continuous rotation servo we carry (4.8 kg-cm/67 oz-in at 6 V). It features two ball bearings on the output shaft for reduced friction, and it offers easy access to the rest-point adjustment potentiometer. The servo can be controlled using a direct connection to a single microcontroller I/O line without any additional electronics, which makes it a great actuator for beginner robotics projects.
The SM-S4303R continuous rotation servo converts standard RC servo position pulses into continuous rotation speed. The default rest point is 1.5 ms, but this can be adjusted by using a small slotted screwdriver to turn the middle-point positioner. Pulse widths above the rest point result in counterclockwise rotation, with speed increasing as the pulse width increases; pulse widths below the rest point result in clockwise rotation, with speed increasing as the pulse width decreases. Note that this is the reverse of what is described in the datasheet.
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The servo has an 11" (270 mm) lead that is terminated with a JR-style connector and comes with the following included hardware:
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This robotics servo is compatible with our servo controllers and has a Futaba-compatible output shaft, which means it works with our servo wheels and sprockets. For detailed specifications, please see the specs tab.
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Micro Maestro 6-Channel USB Servo Controller (Assembled) |
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0.100" (2.54 mm) Breakaway Male Header: 1x40-Pin, Straight, Double-Sided |
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2-5/8" plastic Black wheel Futaba servo hub |
Data sheet
Manufacturer BTC Korporacja sp. z o. o. Lwowska 5 05-120 Legionowo Poland sprzedaz@kamami.pl 22 767 36 20
Responsible person BTC Korporacja sp. z o. o. Lwowska 5 05-120 Legionowo Poland sprzedaz@kamami.pl 22 767 36 20
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SpringRC SM-S4303R Continuous Rotation Servo