Hi all. I’m new here and in this CNC business. My question is, is there any coolant/lubrificant that you advise me to use? It’s for a normal cnc mill machine (metal, aluminium, etc)
Thank you all 
I use a water based lubricant at work get it from a place in Bradford called lubico
in a few moments i use water with a bit of soap more or less 1:50, alcohol with water is good too
Water with soap or alcohol is not recommended. It will cause rust. It also does not carry away the heat very well. You can use water soluble cutting oil. It is inexpensive and works very well on Al and steel. If you need a small amount you can order it from Little Machine Shop in Pasadena.
I can confidently recommend Dromus oil as a lubricant for most metal milling. It’s been in the industry for donkeys years, is safe and cost effective. Enjoy your CNC.
You can use a VORTEX tube to cooling the tool, its awesome for one side cold air and for other hot air its amazing you mustbe try! Cheers for all!
The forced air clean the bits and cooling the tool