On Dec 29, 9:44*am, "Bob La Londe" wrote:
What is the best tapping oil/fluid for aluminum? *The oil I am using now is
a general purpose cutting machining oil. *I tap a lot of 10/32 holes and it
would be nice (for convenience) if I could get some more use of of my taps.
I can tap about 40-50 (+/-) holes through 1/2" 6061-T6 bar stock and the
clutch starts to slip on my tapping head. *If I try to get any more out of
it, I'll break the tap within another 2-5 holes. *Breaking a tap off in an
otherwise finished work piece really sucks.

When I replace taps I back off the clutch and then tap a hole. *I'll tighten
it a little at a time, and when the tap goes all the way through with out
slipping just barely I'll give it about 1/32 of a turn more. *That seems to
work pretty good with this head.

The other thing I wonder about. *I have been buying spiral flute taps. *Not
because I need to tap blind holes, but because gun taps seem to be hard to
find labeled clearly and correctly. *I know when I buy a spiral flute tap
its intended for machine tapping. *If I can find clearly marked gun taps for
machine tapping would they be stronger than the spiral flute taps?

I've used Alumicut for threading operations. I had some gummy
extruded rod I needed threaded on the ends. Regular aluminum
threading compounds just left a ragged mess resembling a corncob.
Alumicut left nice shiney threads. Was good stuff. Just googled it,
looks like it's still available, might not have the same composition.
Was a light oily liquid, not like Tap-Magic was.

Stan