Coolant for new Mill

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Coolant for new Mill

Post by thegallery » Wed Aug 03, 2011 1:07 pm

I have have been doing this hobby machinist thing for over 50 years but I have never used coolant. Even an old man should try something new at least once. I have a new PM45 gear head mill that came with a coolant system. I have a concern about water based coolant. Rust is not a friend of mine. I know it is probably in the head. The question. Could I us WD-40 as a coolant? The tank is small, maybe 6 quarts. I know it will be messy, but I would like to try it. Suggestions.
milling 054.JPG

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Re: Coolant for new Mill

Post by stevec » Wed Aug 03, 2011 3:49 pm

Gal, rust in the head is definitely to be avoided! It is an affliction with which I have been plagued. :cry:
As far as wd-40 is concerned I have nothing but contempt for it, I find, if given enough time, it will actually promote rust. It is a water displacer and so can be used to dry wet spark plug wires and such, I suspect this element evaporates with time and takes with it any protection it might have had and, being a faster evaporating solvent, leaves the water behind to wreak havoc on the now cleaned and unprotected metal.
Some pretty good cutting/cooling agents intended for the purpose have been mentioned here. I use Cool-mist and find no rusting problems.

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Re: Coolant for new Mill

Post by JimGlass » Wed Aug 03, 2011 8:04 pm

I use WD40 all the time when machining aluminum.

Here is a spray mist I made years ago to apply WD40 to a workpiece. It has 2 pieces of tubing, one carries the coolant and the other is an air jet.

Coolant drips from the upper tubing and the air jet is below. A small amount of air propels the coolant to the endmill. This system saves compressed air and coolant. I can run all day on a quart of WD40. It also does not cause coolant fog in the air. I still recomend a ventilation system to remove fumes from the work area.

Here is the coolant tank. A 1 1/2 dia PVC. An air regulator is set to about 5 psi to push the coolant out the bottom of the tank or resivor. The a flow control valve to regulate the amount of coolant and a flow control valve to regulate the amount of compressed.

Below is where I tried to make my own flow controls. They work ok but require frequent adjustments.

The first one I made. Good picture of how it works.


Hope this was of interest.

Tool & Die Maker/Electrician, Retired 2007

So much to learn and so little time.

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