This has been a long term project, and has gone through a few revisions. The major revisions were to reduce the hanging distance of the cutter to increase rigidity; and to use a 3phase motor and VFD for more torque over the high speed RC motor I started with. I also revised the elctronics from an all in one parallel port interface / stepper driver to an Ethernet smoothstepper and individual stepper drivers for each axis. The system runs on a desktop PC with Mach3.
An early spindle design, using a timing belt and RC hobby motor.
The current iteration of the spindle, using a CNC spindle from ebay with modifications to fit a standard BT30 collet.
Internally it uses a series of ball to grab the pullstud, which are moved in and out by screwing a locking nut up and down.
The bed used is a 12mm thick piece of aluminium plate, with holes drilled and tapped every 50mm. It has only been that clean once…
I’ve got a webcam set up running through the mill computer streaming back to the house so I can see the progress. VLC batch files on both machines and fixed IPs.
Not the tidiest electrical box in the world, but it does the job, and the aluminium backing plate makes things sturdy, and easy to set up.
A view from the bed, spindle with coolant/air hose at the top, with the 4th axis on the right. The collet/toolholder is not in there at the moment.
An exterior shot showing the 4th axis pulleys and usb numpad which I have bound key to Mach3’s rapid traverse movements. The Y and Z axis are enclosed in a perspex case to prevent dust ingress from other workshop jobs. The tubing is for air/coolant for the cutter, as well as a radiator system for the water cooled spindle. All slides are supported round rail with ballscrew/stepper drives.