3D Printing Wheels and Gears That Work

As Senior Editor of Make: Magazine, I’ve seen plenty of impressive 3D printing projects. One thing that always stood out to me was the ingenuity displayed when people come up with ways of printing mechanical parts that come off the printer already interconnected and ready to move. Imagine, for example, printing a toy car on a 3D printer and not having to assemble anything, it just comes off the build plate and is ready to roll with functioning axles and everything.


Well, if you’ve played around with additive manufacturing, you’re probably already imagining all the problems you’d run into when trying to design something like this. Frankly, the task seemed daunting to me, but I was intrigued, so I dug in to figure it out.


Let’s break down how this works. As you already know, a 3D printer lays down one layer at a time, building on top of the previous. It can’t simply print into thin air, so you either need to print sacrificial support structures, or use draft angles that the printer can handle for these overhanging structures. In this case, I’m using 45 degree angles, which the printer has no problem with, to create captive axles.

In this section view, you can see how the wheels and axle are captive to the body


There are a multitude of ways to do this, but the way I’ve found to be easiest within XDesign is to extrude and set the draft angle at that point. This requires a bit of pre-planning but as you can see in the video it can be quite effective.

One tip to keep in mind, most printers can print pieces that are roughly .5 mm from each other without accidentally fusing them. Of course if your printer isn’t dialed in as tightly as some, you may want to widen that gap, but be aware that this might result in a bit of a loose fit for some.

On a side note, one thing I really like about 3DEXPERIENCE SOLIDWORKS For Makers is that it is browser-based, allowing me to warm my toes by the fireplace during some unreasonably cold weather we were having.

Caleb Kraft

Caleb Kraft is senior editor of Make Magazine. In his spare time, Caleb designs and 3D prints accessories for gamers with disabilities.

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