Snap switches are great for temperature control of fans. I'm using some to 'automate' my temporary wood boiler in my shop.
Most cheap vfd's dont support external braking resistors. But, like every other electronic device, i'm sure some hacking can be done. Both my current lathes have mechanical magnetic brakes. Both were easy to integrate into the control scheme of the vfd's
On my big lathe, because the vfd supports it, i use both a braking resistor and the mechanical brake. Mostly to avoid tripping the drive on quick decel, which would happen when i first set it up, where the mechanical brake was not in use and no external resistor. With a heavy 14" 4 jaw chuck, i had to have an 8-10 second decel time, or it would trip. With the resistor I got to 4-5s, with both 2s, easily, from 1500 rpm.
On my smaller Emco machine with the Teco L510 drive, i couldnt have an external resistor, so i had to set the brake to come on at 19hz, where the lower limit of my pot is 20, so the brake didn't come on when i turned the speed down, so they didn't clash. It stops very quickly though, even at full speed. Much less inertia. I'm sure if i played around with it more I could make it better, but it works great.
