Cutting Oil Recommendations

[Greg]

what cutting oil or coolant is needed for

Stainless Steel ?

Hard Copper ?

I will be using a lathe to do some light machining

turning tools recommendations would be appreciated also

thanks for your help

[Outpost75]

For the home shop nothing beats Brownell's "Do Drill"

http://www.brownells.com/gunsmith-tools-supplies/general-gunsmith-tools/taps-dies/tapping-cutting-fluids/universal-do-drill-prod1120.aspx

[Greg]

thank you
I'll place it on my order

[IllinoisCoyoteHunter]

I recommend HHS for cutters. Cheap, easy to customnize, and can be used at lower speeds.

[Lead Fred]

I got a can of Tap Magic when I converted some 8mm to 8mm-06
Been using it even since

[smokeywolf]

For stainless and Titanium, for about 3 decades now, I've used some stuff called "Molecular's Tapping Compound". Used to buy it from Molecular Products in Maywood, Calif.

For the copper, hard, soft or any other, a 70/30 mixture of Relton A-9 and kerosene.

For machining stainless, carbide is the cutter of choice.

For your "hard copper" I would think a TiN (Titanium Nitride) coated HSS (high speed steel) cutter would do the trick nicely.

[imashooter2]

50/50 kerosene and ATF always worked fine for me. Cheap is just a bonus.

[deltaenterprizes]

I have read that milk works for machining copper, but I have never tried it, it came from an old time machinist.
Smokeywolf is right, carbide works well on stainless , HSS may work on some low grade stainless but have had HSS drills do nothing to a kitchen sink I was trying to put a hole in.

[country gent]

For hard copper at work we used the waterless hand cleaner for cutting fluid. For stainless black cutting oil the original tap magic worked decent but discolored machine parts ( ways on lathes, tables on mills and drill presses) when working with stainless.

[Vann]

I'll second Tap magic.

[BigEyeBob]

I have read that milk works for machining copper, but I have never tried it, it came from an old time machinist.
Smokeywolf is right, carbide works well on stainless , HSS may work on some low grade stainless but have had HSS drills do nothing to a kitchen sink I was trying to put a hole in.

also lard can be used for copper ,another old time fix.

[footpetaljones]

also lard can be used for copper ,another old time fix.

Lard oil is what I see recommended in anything printed before the 60's. Good luck finding any of it, though.

[smokeywolf]

I used to use lard oil mostly for low carbon steels.