Flood coolant?

How about a water-soluble oil? I use it in my rotary surface grinder and lathe.

I do the same and have been rather happy.

High sulphur based cutting oil. No toilet water for me, except in the mist sprayer, which seldom gets used. Then its KoolMist.

"Lenin called them "useful idiots," those people living in liberal democracies who by giving moral and material support to a totalitarian ideology in effect were braiding the rope that would hang them. Why people who enjoyed freedom and prosperity worked passionately to destroy both is a fascinating question, one still with us today. Now the useful idiots can be found in the chorus of appeasement, reflexive anti-Americanism, and sentimental idealism trying to inhibit the necessary responses to another freedom-hating ideology, radical Islam"

Bruce C. Thornton, a professor of Classics at American University of Cal State Fresno

My favorite is BioCool 500, a synthetic whatever that means. "The Kid" got me several pails while at a previous job. I find that the mix gets richer as it evaporates - you're only losing water not oil. I got a coolant % tester off eBay. When it gets over 7%, I add 3% coolant, saves almost half. Otherwise, I add 5%. 3, 5, and 7 percent feel different; you could just thin your adds when it starts feeling too oily.

Karl