So this week I decided to finally build a proper lego CNC. I want to cut stuff and make stuff and CNCs are great for doing just that. But they are really expensive. And I had some old lego hanging around so I decided to see what I could cobble together.
One of the biggest problems when building a Lego CNC is parts. A lot of geared parts are required to make tracks for the X and Y axes. So I decided to build a polar CNC. This is a CNC where there is a rotating platform and an X axis. These two axes combined can move a laser or drill to any position over a piece of material. This method of movement requires much less parts leading to a simpler CNC to build.
I didn’t want to have the high RPM’s of a drill ripping apart my CNC with torque so I decided to use a laser out of a DVD player to do the cutting. I tried some CD lasers but they didn’t work. I’ll have to get one online.
The design is very simple and has a slight reprap feel to it. It is very strong and rigid though as proved by these test cuts with a pen in place of a laser.
The center one is the best because the CNC actually went over those lines 3 times. And I can’t tell unless I bring the paper right up to my eye. Here’s a video showing the CNC in action. It was an early print back when I was using rubber bands to hold down the paper. Now it uses magnets.
It can print out a lot of pretty spiral patterns pretty quickly. It took around 3 minutes to print the one next to the coin. Here’s a pic of the CNC at the moment with two CD drive magnets to hold down the paper and an aluminium build platform.
So that’s about as far as I’ve gotten. I’ve got it to draw pretty circle patterns that I can design by changing the variables in the Mindstorms NXT program. I’ll keep you posted and keep working on making it larger as well as writing some software so it can draw squares and triangles. Hmmm maybe it should be called Polaris……..