The objective
A 3D-printed chassis designed in OpenSCAD to hold my Motorola Moto G55 and accept LEGO wheel assemblies at each corner. Seven iterations, a pile of failed 3D designs and a successful print, and some very specific BrickLink orders. Still the most satisfying build on the workbench right now.
I’m doing this for a smart car parking demo, I’m recreating, similar to something I built at Worldpay.
I wanted to build a car chassis for my Motorola Moto G55 smart phone. At the moment I’ve created a design that accepts LEGO wheels. Trying to find LEGO wheels that attach to LEGO blocks was an absolute nightmare. Mainly as you can’t buy them in sets, and I kept buying the wrong sized wheels or axels ha.
Feb 2026
I didn’t know where to start with creating the 3D model or making it printable. So I used Claude – I uploaded an image of the existing chassis, and described what I wanted. It did a good job creating a 3D model in OpenSCAD. There was then several iterations to remove the wheels, and get sections cut out to take LEGO.
Finally I wanted the back to not be solid, but to have gaps / panels, and a gap for the phone’s camera. I got this printed, and the only fail was the gap was in the wrong side, to the left, not the right – I had not noticed that. So the next step is to cut this bit out too.
Photos, videos and 3D model to follow.
3rd May 2026
I have now got wheels that fit. The next step is to attach them to the lego chassis, for stability I want to buy an extra couple of lego pieces as a base to the lego pieces, and then I will probably use superglue. I’m not 100% happy with the chassis having a thick section either side – but that is good enough for the first attempt. I’m keep this updated!
