Hi Steven,

We didn't have the original software and Mach3 seemed to be the popular choice and has a large community to support it etc. I may also give LinuxCNC a try at some point but thought that Mach3 would be a good starting point. We were also reluctant to ripout all the boards but not being able to interface to them made them pretty much no use to us. Also I had read that modern drivers would be an improvement over the ST ones it used. We ripped out almost all the control boards and left the Spindle controller, main power transformer rectifier, cap etc and the Choke for the spindle. We then rewired everything to get a good understanding of what wire did what etc.

Pokeys was chosen as I had a laptop spare that didn't have a parallel port and I had read all-sorts about timings being off with laptops and external converters. I started looking for external Pulse generators that would work with Mach3 and Pokeys was mentioned in a couple of posts. It was a bit of a gamble bit its been pretty easy to get that side of it setup. We use the USB version but there is an Ethernet version too. From what I understand the Pokeys plugin attaches to the Mach3 core so all the steps are counted in the pokeys itself when its running. You can use the pokeys direct with the drivers but we also opted for the CNC addon which adds a couple of relays and also expands the features of the pulse engine to allow more axis etc. It also makes connecting to their stepper drivers easier.

So far we haven't interfaced with the spindle controller directly or with the existing home switches but I plan to take a look at that next. We setup the Stop button to trigger the E-Stop in Mach3. We have since had the machine cutting some parts in Ali which it does a treat although we did have a couple of issues with needing the swap the stepper wires for the Z axis to get the axis going in the right direction (0 at top).
We also need to tune the steps/mm but we roughly did this by clamping a digital caliper in the vice and jogging the tool and adjusting the values. Its a bit crude but it got us to within a few points of a mm which is fine for testing etc.

Would be interesting to see what you go with and how it fares.

Cheers
Martin