The Railroad Hand Car 13


Makit proudly presents... The Railroad Hand Car! It is scale model of a hand car that works with a micro motor and a switch to turn it on-off or change direction. It also has an optional driver and a wagon.

Below you'll find step by step instructions to assemble the hand car. You can also use them to mount the trailer (I didn't write separate instructions because if you have already assembled the main car, the trailer should be pretty straightforward).

You'll need to solder the switch but, don't be afraid, it is not a complicated soldering job and could be a good first try!


There is one straight track and one with 22.5 degrees of rotation. You can mount them and change them easily on a flat surface. If you want to make the track more permanent, you can print some track clamps and secure the connections. In fact, I'm working on hanging a circuit from the roof! I'll show you when it's done. 😉

You can also print them with two colors to get a more realistic look.

If you like it please click “like” to support my work and don’t forget to post some pictures of your print!!

Printing settings

All parts print without supports. I used my ZYYX+ 3D printer and printed all parts with 0.2mm layer height and medium settings (3-4 perimeters and around 20% infill).

All parts use PLA except for the tyres (semiflexible filament) and platform and trunk (wood PLA to get a more realistic look).

Parts and components

In addition to the printed parts, you’ll need:

For the trailer, you'll need the same except for the motor, switch, battery and cables.

Watch the video in action!!

⇓ Download Makit's Railroad Hand Car and wagon from MyMiniFactory



Step 1

First, insert axle gear into rear axle. Then insert four bearings (18x12x4mm) into the front and rear axle.

Railroad hand car Assembly Step 1

Step 2

Insert axles (with bearings) into the body sides and hold them to body front parts with four M3x10mm screws. See the picture for correct orientation.

Railroad hand car Assembly Step 2

Step 3

This can be a tricky part. Insert first two M3x20mm countersunk screws into the main gear and main-gear-2 part respectively. Now, insert the connecting rod and use one M3x12mm screw and nut to secure it, but don't overtighten it too much for now (this is because you will need to move them a bit to tighten the screws in the following steps). See picture for more details.

Railroad hand car Assembly Step 3

Step 4

First, insert two M3 washers in each M3x20mm screw and using body-arm and body-arm-motor, assemble the main gear from previous step. Use two lock nuts but don't overtighten them as the screws have to rotate freely. See picture.

Railroad hand car Assembly Step 4

Step 5

When previous step has finished you can now tighten the M3x12mm screw and nut from main gear.

Railroad hand car Assembly Step 5

Step 6

Now, put body arms in place and secure them with four M3x10mm screws.

Railroad hand car Assembly Step 6

Step 7

Follow the picture for soldering the switch, motor and battery cable. Don't be afraid about this step, it is not a complicated soldering job. I'm not very experienced myself 😛 I soldered it in a position that fits the car perfectly, so I suggest you use the same layout.

Railroad hand car Assembly Step 7

Step 8

Put switch and motor in place.

Railroad hand car Assembly Step 8

Step 9

Secure motor with the motor bracket and one M3x10mm screw and nut. Now secure the switch with the switch nut. I suggest you try the motor by connecting the battery to ensure everything works correctly.

Step 10

Using four M3x25-30mm screws and 8 nuts, assemble the swing.

Railroad hand car Assembly Step 10

Step 11

Put the platform and the bridge parts toghether with two M3x8mm screws. See the picture to mount the correct ones in this step.

Railroad hand car Assembly Step 11

Step 12

Now insert the needles into platform and assemble the trunk.

Railroad hand car Assembly Step 12

Step 13

Mount the platform into the chassis with two M3x8mm screws above (paltform to the chassis) and two M3x25 screws below (through chassis to bridge).

Railroad hand car Assembly Step 13

Step 14

Secure the two magnets into the bumpers with two M3x10mm screws. Bear in mind the polarity of the magnets. You'll have to mount one opposite to the other in order for them to atract each other.

Step 15

Then secure the bumpers to the car with four M3x8mm button screws.

Railroad hand car Assembly Step 15

Step 16

With one M3x35mm screw, two nuts and a lock nut mount the swing on the bridge.

Step 17

Secure the connecting rod to the swing with one M3x10mm screw and a lock nut.

Railroad hand car Assembly Step 16

Step 18

Insert the tyres into the rims. Now use four M3x8mm screws and the wheel plastic nuts to mount four wheels.

Railroad hand car Assembly Step 18

Step 19 (optional)

Print two drivers and use eight 15x6.5x2mm magnets to secure them in place using the holes in the side of the platform and trunk.

Railroad hand car Assembly Step 19

And that's it, your Railroad Hand Car is finished!! Now just print your tracks, mount them, connect the battery and enjoy!!

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13 thoughts on “The Railroad Hand Car

  • giorgos stolis

    A very nice project ,I have started with the drivers ,but it seems impossible to print them with moving parts , the only part that moves is the arms at shoulder height.Do you have some suggestions ? Can I print the parts separately and then joint them ?

    • makit Post author

      Hey, glad you like it! 🙂
      I printed it without problems but it’s true that the gap between the moving parts it’s a bit tight and the result will depend on the printer. Unfortunately, the design doesn’t allow to print separately and join later as it is.
      But here you have some ideas you could try.
      I have just uploaded a driver with slightly increased tolerances (search for more gap version). I haven’t had the time to try it yet, but it should work better on more printers. Just be gentle when getting it off the buildplate or it may break. You can also try lower layer height (to 0.1mm for instance).
      Another thing you could try is to reduce the extrusion multiplier a bit. This depends on the printer and I don’t know the exact value for yours, but for example, I use 0.88 with my prusa hephestos and 0.94 with my ZYYX+.
      Hope that helps!

    • Nicholas DeRenzi

      So, I understand how this works, sort of. The driving axle, how is that gear secured to the axle? it looks free-floating in steps 1 and 2…..

      • makit Post author

        Hey Nicholas,
        Sorry for the delay.
        Yeah, I see now that it seems to be floating in the picture but it is not. It’s just that the axle has a flat side in order to print correctly without supports.
        The gear and axle have a dent to keep them in place. However, I suggest you use a drop of hot glue to avoid future possible movements.

        • Nicholas DeRenzi

          Ah ok. Yeah I just made my own and I see what you’re talking about. I used some super glue on it so it’s never coming off haha.

          • makit Post author

            That’s great news!
            Please, if you can, upload a picture to the download page when it’s finished. I’d love to see it 🙂