Not too difficult to remove the Z ballscrew - and, as usual, having removed it you discover how you should have done it! I held the ballscrew on V-blocks on my milling machine table and measured about 0.2mm deflection at the centre. Given how easy it is to deflect the ballscrew this amount with gent...

Well, it was all going well until... Electronics all finished, once I had sorted out motor speed issues. Hadn't realised that the spindle motor needed to be driven at 100Hz to get full speed, but that's done now. Jogging MPG dial plus axis select and jog speed switches all wired, configured and work...

Quick update, just to show I am still working on this one! Stepper drivers replaced with something significantly chunkier, running off 50V AC. Could have used a size smaller and slightly cheaper drivers but because these run off AC I avoided the cost of a rectifier and capacitors, just added a toroi...

Thanks for the comments. I decided to go with the PlanetCNC hardware and software. Every time I look at the Mesa site the desirable cards seem to be out of stock, and despite my IT background (and some Linux experience) it seems like quite a learning curve and project to get it all properly configur...

When I managed to find out the port and pin numbers for the undocumented Chinese USB motion control board in the machine, managed to get Mach3 to talk to it, and added a missing wire between it and the driver board, things started working. However, it quickly became apparent that the 24V supply plus...

I have just acquired an Orac which seems in reasonable condition mechanically, but I'm less sure about the electrics! I understand that it came from a school originally; the next owner stripped out the original electrics and replaced it, and the last owner (now deceased), I was told, had it running ...