What makes you you think the compressor is worn out? Longer recharge time? Different sound, oil in the drain water?
I'm running an IR T30 5hp able to keep up with two air sanders, and operate my Joos veneer press.
Try cleaning the electric contacts in the pressure switch if you here the motor bogging down. Fooled by that for a couple of weeks.

Thanks for all the information and help.
I was looking in the manuals for some of my equipment, and they state the air pressure, but they don’t state the CFM required so I am not really sure how much air a cnc uses in CFM. Maybe I am blind when reading the manual.

Thomas,
I was worried that my compressor was getting tired as it lagged on startup the other day. I will clean the contacts and hopefully that is all it is.
My compressor is I would say maybe somewhere between 15-20 years old, but it has been used gently for the last 10 years, there are lots of days when it doesn’t get turned on. It is also a T30 with a horizontal tank.

Thanks again.

Similar symptoms to mine.

Its worth a diag. Start/run capacitors getting weak, along with several other factors.

Air demand for a "cnc" is not that simple, spindle type, tool changer, air blast or not, pneumatic drill blocks, yada yada.

My cnc, 10hp HSD, 10 position ATC, no air blast, uses virtually nothing for air.

Barring air blast or dynabraes, wide belt, edgebander, etc are all relatively minimal especially if its not an all at the same time situatuion.

Swapping out a.compressor for possibly a couple hundred in parts and labor is something worth looking into.

Quick look and the model we have is up close to a grand from purchase a 6 years ago.

Compressors have an unloader valve. If not working properly the compressor will start hard or may stall. When compressor hits the cutoff pressure it shuts the motor off and then you hear the hissing sound this is relieving pressure so the motor is not under pressure the next time it starts. If you turn switch off or unplug the unit and let it drain completely down to zero then try to restart and it has no problems getting up to pressure but has problems when hitting the cut in limit it may be unloader valve. An easy fix and not that expensive of a part.

It is pretty easy to rebuild an air compressor. I have a t30 that I have rebuilt a few times. It still works well but I knew our consumption was up by just how many times it turned on and how often. There is more than just cfm of the machines. How old are your machines ? Old pneumatic valves can leak a little bit, old air tubing can become brittle and leak. Just how old I are your supply lines and do the leak? Add that all up and you could be losing a lot of air besides just using it.
I knew my old piston pump was working way to hard and was going to go down sooner or later so I started looking for a new compressor. I found a good used rotary screw that fit my shop very well. It had low hours and was very clean. It had the same hp motor as the piston but puts out a lot more air. We never run out of air now and have the old piston as a back up. We ran the tanks together for more storage but found out that the screw put out so much more air that we really did not need the extra storage.
The draw back was that the motor runs for the entire shift and the screw only works when air is needed. That is the way it was designed to function. That increase the electric bill by about $50 a month. All in all I am very happy with a rotary screw compressor and should have purchased one a long time ago. I have not had the first hiccup out of this machine, and it almost feels like it wants to go work everyday. Like all machines keep up the basic maintenance and they will serve you well.

I have a 15hp screw. It's more than I need. I could probably get by just fine with a 10hp.
I wish I would've bought two smaller units and set them up to run as a backup to the other. Either for mechanical issues, if one goes down, I've still got the other.
Or for air draw, if one can't keep up, the other kicks on and makes up for it.