Computing stuff tied to the physical world

CNC progress

In Hardware on Nov 20, 2009 at 00:01

The CNC router is coming together nicely. The controller board works so far, and so does the EMC software running on a Dell laptop:


Here’s the complete setup, next to the V90 (the electronics will go inside once finished):


And here’s the EMC 2.3.4 software, running under Linux (Ubuntu 8.04):

Screen shot 2009-11-15 at 16.10.16.png

It just finished “doing” the demo, i.e. making the motors turn in lots of mysterious ways.

Some tech specs: the laptop has a worst-case real-time jitter of around 17600 nSec, which means the computer can send out up to 30,000 steps per second. I’m using quarter stepping, so that translates to 800 steps per rev, 4000 steps per inch, i.e. max about 7.5″ per second on the X and Y axes (which the motors can’t handle anyway – I may switch to 1/8th micro-stepping later). The system uses imperial units for the screws, so that’s what I’m sticking with, but I’ll probably do most designing in metric units. Resolution of the machine is about 0.006 mm for X & Y, and even higher for the Z axis. Don’t know about accuracy, repeatablity, and backlash yet – that’s where lots of tweaking will probably be required.

Next step is to mount the motors on the V90, and then go through all sorts of adjustments to make this thing move properly in all three axes. Oh, and hooking up the emergency button and the six limit switches.

And that’s just the CAM side of it all… CAD will be a completely different story!