[HELP] Coolant for the home hobbiest

[Dr Stan]

I worked as a machinist & tool maker for several years and consequently had multiple experiences with rancid water soluble coolant. Consequently I'm using a 50/50 mix of cutting oil and diesel fuel in both my lathe & mill. Its a compromise but works fairly well in ferrous and non-ferrous materials. Some will complain about the smell, but its one I like as it takes me back to my early days in the trade.

BTW, I've had contact dermatitis from water soluble coolant, but have never had it from oil based.