# Milky substance using in milling/lathing?

**URL:** <https://boards.straightdope.com/t/milky-substance-using-in-milling-lathing/192303>\
**Category:** Factual Questions\
**Created:** [August 1, 2003, 5:52am UTC](https://boards.straightdope.com/t/milky-substance-using-in-milling-lathing/192303 "2003-08-01T05:52:48Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![dnooman](https://avatars.discourse-cdn.com/v4/letter/d/839c29/32.png) [@dnooman](https://boards.straightdope.com/u/dnooman)\
**Post date:** [August 1, 2003, 5:52am UTC](https://boards.straightdope.com/t/milky-substance-using-in-milling-lathing/192303/1 "2003-08-01T05:52:48Z")

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I assume it’d meant to reduce friction and or heat , but what is it made of, and is it a lubricant?

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**Author:** ![Doc\_Nickel](https://avatars.discourse-cdn.com/v4/letter/d/5fc32e/32.png) [@Doc\_Nickel](https://boards.straightdope.com/u/Doc_Nickel)\
**Post date:** [August 1, 2003, 6:42am UTC](https://boards.straightdope.com/t/milky-substance-using-in-milling-lathing/192303/2 "2003-08-01T06:42:46Z")

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It’s a solution of water and [water soluble oil](http://www.itwfpg.com/rustlick/machining.html).

The water acts as a coolant, the oil acts as a lubricant and helps keep the water from corroding the workpiece or the machine itself.

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**Author:** ![dnooman](https://avatars.discourse-cdn.com/v4/letter/d/839c29/32.png) [@dnooman](https://boards.straightdope.com/u/dnooman)\
**Post date:** [August 1, 2003, 6:58am UTC](https://boards.straightdope.com/t/milky-substance-using-in-milling-lathing/192303/3 "2003-08-01T06:58:58Z")

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Great site! Thanks for the info.