Introduction: 3D Printable Robotic Actuator

About: I'm a content creator. I make open source projects and videos for said projects. My goal is to create free and open knowledge for everyone.

Upon research for an upcoming project, I discovered this simple way to make very tiny magnetic actuators. RC enthusiasts have been using these for some time now, but they don't seem very well known. I think there are a lot of useful applications for these little actuators, and they are simple enough to be designed by anyone, which means easy to implement in custom projects. Follow along in the video as I show you how to make the one designed and I will explain how it works. Although I have provided the files to 3D print my design, I encourage you to try and design your own!

Step 1: Watch the Video!

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Step 2: Gather the Parts and Tools


  • Magnet (I used this one for my design - McMasterCarr)
  • Metal Rod - 1mm Diameter - I used the leads from a resistor.)
  • Copper Core Wire, at least 30AWG - AdaFruit - or scavenge from old motor or electric clock.
  • Electrical Tape


  • 3D Printer, or a service like Shapeways
  • Soldering Iron(if you want to solder the leads on)
  • Snips
  • Tweezers(not essential)
  • Patience (to wind the wire)

Step 3: 3D Print the Parts!

Download the parts from here! -

3D print the parts.

Step 4: Assemble the Body.

Cut some pieces off of your metal rod(resistor in my case) and assemble the piece as shown in the GIF above. The small pieces of rod hold it together.

Step 5: Electrical Tape

Use the electrical tape to cover the holes where you put in the metal rod, this makes sure they won't fall out.

Step 6: Start Coiling the Wire

Attach the wire to the frame and start coiling it around the circular part of it. Keep it going in one direction. The neater and tighter the coil, the better the magnetic field will be for the current that is supplied. Once fully wrapped, strip some of the enamel off of the wire and solder on some pin headers.

Step 7: Test It Out!

I'm testing it by attaching it to a motor driver and microcontroller. This isn't an Instructables on how to do that so I won't go over it(I do cover some of the stuff in some other Instructables). Basically if you put a current though the wires(such as attaching a battery to each side. The coil will generate an electric field. The magnet will oppose that field in some way, and try to spin the actuator arm. This is what gives the movement. If you switch the polarity of the current(battery) it will make the actuator try and go in the other direction. Lots of explanation int he video. Very cool!

Step 8: Design Your Own!

Since these are pretty simple in design, I encourage you to try and make a custom one for your own application. I would love to see what you come up with!

Step 9: Support These Projects!

If you haven't noticed yet, my goal is to bring fun, interesting, educational projects that are available to everyone equally with zero pay walls. However, these projects do cost me both time and money in developing them. If you enjoy these free open source projects, and can spare a few dollars a month, please consider joining my Patreon. Patrons help support future projects, so I can continue to bring more content to everyone!

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