Building the Linear Generator

A linear generator is a simple electromagnetic device that is capable of  generating electrical current.

Step 1

Fabricate Generator Parts


CAD Files: Download

Laser Cutter Files

There are three file formats (PDF, AI, SVG). Select the format that is compatible with your machine’s software. 

Laser Cutter Material

To build the generator, we use 1/8″ baltic birch plywood (source: Inventables). If you use a different material, be sure to adjust tolerances on the CAD file.

3D Printer File

There is a single file in the downloaded package (end-cap). Open the 3D printer software and import the STL file, print four end caps for the motor. 

Step 2


Assemble the laser cutter parts together to build the body of the generator. The pieces should press-fit together. A hammer can be used to tap in parts into the corresponding holes.


Press the spool holders and the end stops into the motor base.

Step 3


Finish the assembly of the generator body by attaching the four feet to the bottom of the base. Again, use the hammer if necessary.


At this point, the generator body assembly should be completed.

Step 4


Assemble the two banana jacks onto the generator base. There are two holes cut out towards the back that will fit the jacks. You will need to unthread the nut and remove the washer. Attach and tighten the nut and washer onto the base.


Here is how the banana jacks should look after you attach them to the base.

Step 5


You will now need to use the solenoid made in the previous unit. There should be two trough pieces that connect to the end of the solenoid. Gather all of these pieces.


Attach the two trough pieces to each end of the solenoid. These will guide the magnet in and out of the solenoid.


Finally, attach the solenoid assembly onto the generator base. The troughs should rest on top of the generator base as shown in this photo. Guide the two ends of the solenoid wire through the small holes located below the solenoid tube on the base. 

Step 6


You will need to solder the two solenoid wires onto the terminals of the banana jacks.


To make the soldering process easier, take each wire from the solenoid, remove the red insulation coating, and wrap it around the terminals as shown in the photo. This will keep the wire in place as you try and solder it.


Finally, solder the wire to the banana jack terminal.

Step 7


To assemble the armature of the generator, you will need a permanent magnet, piece of iron rod, and a 3D printed plastic end cap.


Connect the end cap to one side of the iron rod, hammering this in if necessary. Then connect the magnet to the end cap. This armature is what moves inside and out of the solenoid to generate electricity.

Step 8


To make the armature easier to manuvear, you may bend the iron rod towards the end sticking out of the generator. This process creates a handle for you to use.


Your final generator should look like the photo on the left.