Cutting oil or coolant for drill press

Actually Dan, hydraulic oil makes lousy cutting oil, not even close to being 90% as good as the best possible cutting oils or coolants. Lubricating oils in general make lousy cutting oils. In fact, when using water soluble cutting oils in machine tools the lubricating oils used in those machine tools for the ways and ballscrews contaminate the coolant and cause it to be much less effective in preventing cutting tool wear as well as proper chip formation. This is the main reason why I use oil skimmers to remove tramp oils from the coolant used in my machine tools. Eric

Thanks for the correction. For years I have used what ever is handy including ATF. And believed it was much better than nothing.

Dan

Maybe better than nothing, but certainly not as near as good as cutting oil. Have you tried bacon fat? Even bacon fat is better than motor oil. Seriously. Eric

With all of the stearin in it, it won't wick by capillary action. When you take the stearin out you're left with lard oil -- which has a decent set of properties (and a very long history) as a cutting oil.

Bacon fat wicks OK when the metal is good and hot. BTW, how is the stearin removed? I have always wanted to make lard oil. Eric

This doesn't answer your question but it's a good, concise explanation of the chemistry of fats and oils.

The strange traditional names indicate their sources, for instance 'capr..' refers to a goat.

-jsw

Thanks... Maybe, use light weight hydraulic oil and throw in some sulphur also.

i

Look for "Manteca" in the foreign food section.

-jsw

replying to Ignoramus14609, ctvc255 wrote: Thanks, I learned something new here!

replying to Ignoramus14609, ctvc255 wrote: Thanks, I learned something new here!

Looking around on tbe internet , I can find lots about using Boraxo to remove rust , but nothing about using it and water as coolant for machining. And nothing about why Boraxo in water prevents rust.

Does anyone have any information on this?

Dan

Boraxo is a mixture of borax (around 80%) and sodium soap. Borax is quite alkaline -- it's sometimes used in electrolytic de-rusting -- and steel or iron in an alkaline environment usually resists rust. (It has to be continuously covered.)

Borax also is quite abrasive until it's dissolved, so, mixed with soap (as in Boraxo) it's good at removing tough grime. I keep a container of it in the trunk of my car to clean up after gutting and filleting fish. d8-)