Posted by Lainchy on 12/09/2019 09:39:56:
I've searched the forums, and found solid answer, each preferring their own solution. I guess I'm looking for a neat, thin, coolant that doesn't cause any of the fore mentioned pitfalls.
I know WD40 isn't a lubricant, but what about GT85? That IS supposed to be a lubricant. Is there a product that anyone recommends that can be used as a coolant / cutting spray that can assist drilling (since that's what we used it for on the course)
Ta 
On steel, for turning/milling, I often cut it dry. Depends on circumstances.
If I feel I need to use a lubricant I am currently using Ambersil Tufcut, just because I have a bottle sitting around.
I also use 'Neatcut' (Google it).
I have a suspicion that Neatcut labelled up by various suppliers is nothing but ISO 32 hydraulic oil.
I have a very low general opinion of today's formulation of WD40. Jack of all trades, master of none. The lubricant content is a mere 5%.
It is, however useful as a lubricant for aluminium (as is paraffin, which is much cheaper).
I have GT85, but I use that as a mountain bike lubricant!
Basically, the more well known branded product, the more you will pay for it, and you don't need to.
Edited By David Standing 1 on 12/09/2019 10:53:00