Newbie- Coolant selection help

[moldmaker5]

I posted this in the wrong forum. Sorry for the double post.

Hello All!

Im having a bit of trouble deciding on coolant for a new machine thats being set up strictly for drilling.

I am going to run strait oil through one of those crazy Mitsubishi drills that are .0745 diameters with 25:1 L/D ratio. And its coolant through at 1000psi in a Haas VM3. Very small holes.

I will be drilling 6061 but also some 360 brass and 303 stainless.

I am thinking of running Hangsterfers Missilelube XXL as I have had good experience with it in my VF2 and Mori lathe. It also has a rather low viscosity of 6 cSt @ 40C. It foamed badly when shaken in a bottle but that went way down after adding a drip of their anti-foam additive.

Also suggested was their synthetic NG Hardcut. It is double the viscosity but doesn’t feel oily.

Does anyone have experience running oil through small, long L/D drills?
Does anyone have cavitation issues in a high-pressure pump?

Any other comments or suggestions would be greatly appreciated.

Thanks,
Jesse

Oh, and we use oil because the owner will only use oil. On that I have no say