the TM only uses air for tool changes. Only for the tool change spindle draw bar
The VF used WAY MORE!
the VF (unless greased spindle bearings) used air for the air/oil spindle mist lubrication. I'd say about 3CFM is consumed whenever the spindle is running just for the spindle bearing lube
The smtc used air for the pocked drop down, tool change spindle draw bar, the TSC uses a purge air blast.
Im literally compressor shopping right now because i want from a TM to a VF a few weeks back.
my 4cfm costco compressor hardly outputs enough for the spindle lube system, add a few tool changes and im low air pressure.
keep in mind your feeding the spindle bearings that air, you want CLEAN AND DRY air!!
lots of choices out there. im likely going with a 5hp screw compressor as i use lots of air blast doing milling on 4140 and want the extra air.
im gonna look at one of these next week, quoted $7500 canadian for a 60 gallon tank, 5hp screw, 1 micron filter air dryer combo.
made in Canada to boot
A5 Rotary Screw Air Compressor | DV Systems
of course the compressors gonna depend on your overall shop situation/needs/volume/price point