I'd like to know what lubricant do you use for machining mild steel(tapping oil? Synthetic 10W motor oil?, cooling fluid?), I have been using the leftover tapping oil from the shop I used to work at many years ago but it's running out , I went to order some more and wow, there's all kind of cutting oils on the market,I chose Tap Magic so far, but it's $16 for 4 ounces, is there a better choice? how about Safe Tap? Another question, I was wondering if any of you ever spray cooling fluid to save your cutting tools?I'm trying to avoid cooling fluid on my mini mill , spraying water/oil mixture is messy IMHO,plus, I need to put some type of tray under the mill which is not practical the way I'm set up.