Small Cartesian coordinate system. Useful for any kind of demonstrations or in robotics projects, or as addition to a motion capture system.

Original file is 40mm x 40mm x 40mm. 

It should be ok to scale it up, but I have not tested that.

Every axis is placed on separate plate so it is easier to print each in a different color. As you can also see on the photos, my preference is for:

• x → red
• y → green
• z → blue

But there is also a separate plate with all of the axes in it, if you wish to print them in single color.

Assembly

Assembly requires glue. I use regular cyanoacrylate glue.

To help with the alignment during glueing, each axis has a small cone and matching cavity. 

My process is to first glue two axes flat on the desk.

Once the glue cures, flip them around and slide the third axis into the remaining slot (with glue, of course).
 

When assembling be careful about order of glueing as you might end-up with left-handed coordinate system (unless this is what you want; in that case, go ahead :) )