08 November, 2011

My Second CNC Router Project

I'm writing this article retrospectively, really as a what not to do more than anything else.

Unfortunately at the time of writing this I have not found any photos of the completed beast but below you can see an early photo of the build process with the X and Y axis part completed.

Looking back it was flawed from the outset because of the size and choice of materials.

In my humble opinion, MDF is not suitable for CNC Routers over about 500mm in size. This beast had a footprint of 800mm x 600mm. I used 18mm MDF that was doubled to 32mm in critical areas, yet it absorbed humidity and sagged under it's own weight.

Just found this rare photo of #2 in it's complete state

In addition to the MDF issues, I used M8 threaded rod and M8 bolts for the leadscrew and ballnut. At the length required to drive the long axis, the threaded rod, flexed and wailed like a scalded cat under load.

Finally, a movable gantry is way more difficult to make rigid for those of us who are financially challenged, than a fixed gantry design as illustrated on my third CNC router. I recycled number two into a table top for my third CNC project.

Having said all that, it was a capable tool right up until the moisture absorption and sagging, rendered it inaccurate and full of backlash. Above you can see a large spruce box that I carved with the beast.