Wednesday, 8 January 2014

Converting an A3 printer into CNC machine - In Summary

In short, it's been an awesome project to do, and I would do it again in a heartbeat.  I've still got some tidying up with cable routing, etc, but it has had it's first run with a pen zip-tied to the Z-axis.  The results are pretty good, and the accuracy is nice to see. (

There will be some enhancements and improvements:

  • Upgrade the rails and linear bearings to 12mm,
  • Expand the Z carrier to accommodate a 52mm CNC spindle,
  • Put in a 400W CNC spindle
  • Make the lights on the dash go blinky blink :-)
I would also like to drop in a 4x20 character LCD screen and get some output from the Arduino...some sort of job status maybe?

So on behalf of Dasher (she's been sitting here listening to me typing this blog) and myself, thanks for reading.  Feel free to leave feedback or ask questions.  Dasher won't give a fat rats bum about feedback or questions, but I'll do my best to get back you as soon as.

In the meantime, please check out the video of the first run, and I'll update the blog when I do something a bit more exciting than an electronic sketchograph.



  1. Nice Build! Can't wait to see the video.

  2. Video link is at the top of this post...
    Was also featured on hackaday too :-)

  3. Awesome project. It would be nice to hear about your work flow software.

    Thanks for writing this up, it's inspiring.

    1. Thanks for the feedback, most appreciated.

      For anything other than basic shapes and engraving, I'm using Sketchup, exporting the model as a DXF then importing into CamBam. There is some work to do to clean up the model and convert the sketchup curves into real curves, since sketchup uses a series of lines to draw a curve. This can be pretty time consuming on complex shapes.

      CamBam takes some working through, and I'm only at the very basics stage. CamBam itself has a workflow that takes a bit of practice, which I sometimes struggle to remember. This includes setting up the tool profiles for your particular machine and cutting bits. Then there is the concepts of milling operations such as how the rotation direction of the cutting bit affects the order in which cuts are made and the direction cuts are made (climbing vs ramping) You get a real appreciation for the technical expertise of professional CNC and mill operators.

      For engraving tasks and simple contours/pockets,drilling, I make the model directly in CamBam.

      Once I have my gcode file, I feed it into Universal G-Code Sender and it manages the data through to the CNC controller.

      If I used this for more often and had to regularly deal with complex operations, I would be looking at something a bit more industrial strength for both modelling and toolpath/gcode generation.