I am purchasing the x-50. I would like to go with a spindle with a VFD off the start. Is there a best air or water cooled recommended. Does 120 volt setup or 220 volt setup make a difference in performance. Aswell what is max size spindle the x-50 can handle.
with 120 V you should be aware that all your wires and fuses will need to be dimensionated for double the current as if you use 240 V.
A VFD with single-phase input made for a 2.2 kW spindle draws about 4.8 kVA max. power. With 240 V this means up to 24 A current, fuse got to be 30 A, VFD wire size at its input got to be 5.3 mm² (~AWG10)¹. If you want to use the same input power (kVA) with 120 V, you got to double all these currents and wire cross-section areas.
1. (values for VFD with single-phase input. Wire at the input of the VFD can be smaller if you have 3-phase electricity in your house and an appropriate wall outlet).
Note that in the U.S., many people have split-phase electricity (two 120 V phases shifted by 180°) which means even if they seem to have only 120 V outlets (which is between one hot and neutral) they usually have 240 V in their homes (between two hots of different phases) so an electrician can easily install a circuit with a 240 V outlet and circuit breaker.
Regarding which spindle/VFD to use, there are many considerations, mainly dependent on your budget and the accuracy and reliability you expect. There is much information about this in the forum. Note that the spindle/VFD category was only created recently, most topics about spindles and VFDs are still spread around over the forum. Search for spindle and for VFD.
Regarding spindle outer diameter which can be 65 mm and 80 mm (with optional 80 mm mount) on the Onefinity, see the considerations you find if you search for “clear the stepper”
Regarding spindle cable, I always strongly recommend to buy it with the spindle from the spindle manufacturer. Reputable spindle manufacturers always offer this. Many cheap chinese spindle/VFD kit vendors offer only a loose plug and a piece of cable for making the spindle cable yourself, but I can not recommend this. In the case your budget allows only for a cheap chinese spindle kit, you can buy a spindle cable ready to use here.
For the record: Recategorizing to category “Spindle/VFD (Aftermarket)”