29 December 2019
Here’s an overview of the CNC Router Table I’ve been building. The table is mostly operational, and I’ve used it to cut wood for a couple of different projects. But as of Dec 2019, there’s still a lot to finish, including manual and automatic tool change support, fine-tuning system integrity monitoring (like adding a sensor for sufficient air pressure), integrating a jog shuttle wheel, automatic tool length measurement, etc.
The extra 12” provides room for a rack-style tool corral for the automatic tool change function.
Admittedly overkill for this router, the spindle motor is a beautiful, Italian-made, 4.5 kW, 24,000 rpm HSD ES330 Electrospindle. It uses an ISO 30 taper and provides for automatic tool changes using pneumatic pressure.
This is driven by a Delta VFD25AMS23ANSHA high-frequency inverter. Because of the maximum speed, this inverter model is limited to sale to US Citizens. If you’re trying to build a similar machine outside the US, you may run into issues acquiring the necessary inverter (it seems they can be used to drive uranium centrifuges).
Pepperl + Fuchs inductive proximity limit switches from AvidCNC are wired directly into the Mesa I/O card.
Currently using Axis from LinuxCNC, but I hope to move to Tormach’s Path Pilot UI. Unfortunately, they’re built atop an older version of LinuxCNC than I’m using, so integrating their UI will be challenging, and I’m deferring that for now. It’s a shame, because Path Pilot is vastly superior to Axis.
This is proving challenging to integrate.
Automatic tool changing is not yet implemented, but it will be a rack-style tool holder.
The tool change feature of the spindle requires a supply of compressed air, as does the bearing air purge (to help keep it clean of dust and other contaminants). A separate enclosure houses a few air filters, regulators, and solenoids to allow the controller to direct the flow of air throghout the system.