The table build

[Aiph5u (Aiph5u (not affiliated with Onefinity))]

Hey Daniel,

@abrteguy

With/Without VFD?

your question is a little off-topic in this thread, but nonetheless: If you want to use a spindle, you forcibly need a VFD to run it, because a spindle needs three-phase current with variable frequency. That’s what a VFD produces.

@Aiph5u

a “spindle” means a small, cylindrical motor which is usually a asynchronous induction motor. Some VFDs also include support for synchronous (permanent magnet) motor spindles like the DATRON Syncro spindles with which you can mill steel /very/ slowly with high touque, i.e. go down to 1000 or even 100 rpm. Spindles forcibly need a VFD, because they are driven by three-phase electricity with a variable frequency (usually 0–400 Hz). A VFD is in principle an AC-to-DC-to-AC inverter which creates such current on the fly (see also differences between hand router and spindle).

@Aiph5u

Image: Three-phase electricity: Each wave is shifted by 120°.

A VFD is an AC-to-DC-to-three-phase-AC inverter, which means, first the AC input current from the supply line is rectified to DC power, then it is stored in a large capacitor, and then an array of six IGBTs controlled by a microcontroller switches the three output currents on and off to form the three output current waves on the fly.

A “spindle” can also mean a small, cylindrical DC brushless motor which is a synchronous motor too. In this case, the electronics similar to a VFD are integrated in the controller which runs them similarly to a VFD that runs a synchronous (pemanent magnet) motor.