SRT100 actuators

The SRT100 actuators are based on stepper motors. Accurate and powerfull, they allow to build a 2DOF (2 actuators, pitch/roll) or 3DOF sim motion rig (3 or 4 actuators, pitch/roll/heave) for approximately 300€/actuator.

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Summary :

  1. Presentation
  2. Caracteristics
  3. Shopping list

For info: I do not sell ANY PEDALS OR PRINTED PARTS. That would be trading, and I am not, and do not wish to be a trader. I don’t do black either. No need to ask. However, I am looking for a company that could produce plastic parts for those who do not own 3D printers. If you know of any…

1) Presentation

The SRT100 actuator is simlar to the OpenSFX100 actuator, of which it shares an important part of the components. The main difference lies in the motors used : stepper motors for the SRT100, servo motors for the OpenSFX (more powerfull, but also more expensive).

The motor is fixed to the ballscrew, The ball screw nut is linked to a 30mm wide shaft.

2) Caracteristics

The SRT100 travel is around 150mm. Each actuator supports more than 75kg. Beyond that, the speed will be reduced. The Arduino board controls 3, 4 or 4 actuators, thought the FlyPT mover software (free).

SRT100 or SRT150 ? It depends on the type of race you are in and the angles you want to reach. Personally, I have much more angle on my simulator than most simulators I see. For this reason, I prefer the SRT150. But to exploit this travel, you need more speed and therefore more power. This is a good setup if you use 4 actuators. For your information, the further apart the actuators are, the less travel you will have.

3) Shopping list

The full and detailled and updated shopping list is available here.

Electronic :

  1. Arduino Uno (Amazon, Aliexpress)
  2. Cables 3cores 22awg (outer diameter is 4mm). Each driver is linked to the Arduino by 3 wires (pulse, direction, ground).  So you can use 3 wires for each driver, or a 12 leads cable coming from the Arduino, that you then split in four groups of 3 wires (for 4 actuators). It is interesting if the Arduino is far from the drivers.
  3. Power supply 72V 20A (Aliexpress)


  1. Mechanical kit for SRT100/150 actuators : Industry&CNC, partner of Lebois Racing, offer a complete kit for the SRT100 and SRT150 actuators, that includes : SFU1610 300mm or 350mm ballscrew, FK12 bearing, 300x30mm or 350×30 shaft, LMEK30UU linear bearing, 40x30mm 14mm-10mm shaft coupler. Each actuator requires one set. The price is good, and each component has been tested.
  2. 1 extrusion 100100 250mm ou 300mm Kinetics. It is the only compatible model.
  3. Reduction sleeve RH10/M8, self-tapping

Motors :

Nema 34 motor, 12Nm, closed loop and a HBS86H (Ebay)


Screws (one set per actuator):

  • 8 x M8 x 50 (Amazon, Aliexpress) :  To fix the linear bearing support and the fixed bearing support to the Kinetics extrusion.
  • 4 x M6 x 90 (Vis Express, Aliexpress) :  To fix the motor to the Kinetic extrusion
  • 4 x M6 x 25 (Aliexpress) : To fix the linear bearing
  • 4 x M4 x 25 (Aliexpress) : To fix the fixed bearing
  • 6 x M5 x 20 (Aliexpress) : To fix the slider


I've been passionate about cars since I was a kid! I learned the multiple variations of the Skyline R34 through the Gran Tursimo series, until I discovered GTR2 at the wheel of a keyboard. A few years later, I plunged back into Sim Racing with a G27 which made me enter the DIY world. Always looking for an immersion out of reach in reality, I develop projects that I take care to make accessible to any 3D printer owner!
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11 thoughts on “SRT100 actuators

  1. What is the max rpms are this actuator is working? How is the noise of this steppers compared to servo ones?. Many people complain about how noisy these steppers could be, so taking account rpms they are working, how do you compare the noise with a actuator implemented with servo. Is it too annoying?

    1. I don’t know the exact rpm, but it’s slower than servo ones, around 100 mm/s.
      They are mostly as noisy as servo ones.
      It is annoying if you don’t want to use an headset or loud speakers.

      1. Did you think in the possibility of using 2020 Ballscrew? These steppers seems powerful enough to drive them. You would need 3Nm for pushing 140kg cockpit (structure + driver) with only 1000 rpms, getting around 300mm/s from the linear actuator.

        Could you publish a video of them working to get the feel about how the noise is?

          1. Incredible setup there! congratulations.
            With 10mm pitch ballscrew you should get 166mm/s at 1000rpm vs 333mm/s with 20mm pitch.
            At 1000rpm that motor should be pushing around 5Nm safely… at least that it says the theory.
            When you test your new actuator with 1610 ballscrew, would be possible to make a video with the actuator pushing at max speed alone?… To get better what is the real noise without all the background.

          2. Hi ! I am testing the 1610 right now. I use 6400 microstepping instead of 3200 so it’s quieter than 1605 at 3200. In terms of load, I can still stand on the actuator without any problem.
            So 1610 is probably the way to go.
            I will do more testing and a video as you ask.

  2. Hey!

    Very well done putting these lists and everything together. You’ve convinced me to make the leap to motion!

    Do you happen to have any images of the built up actuator arms and / or hardware installation?


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