I do tapping on my VMC 40 all the time,
It does not have rigid tapping, so there are a couple of things I do to keep the tap from breaking
1) use roll taps whenever I can, Less likely for chips to pack up and cause breakage
2) run the spindle not more than 300 rpm, this gives the machine better stopping
and reversing control. I have found faster RPMs , the machine may coast a turn or
so before it reverses and can cause the tap to pull from the holder
3) Floating tap holders are a must, they can make up a bit of error when reversing,
All major tool suppliers have them, they are not as expensive as it may sound
4) use at least a 1 inch rapid plane, especially when tapping multiple holes,
as stated above, taps can creep out of the holder and a watchful eye can
stop the machine if necessary and push the tap back in the holder.
I personally not use a Fadal CNC mill as a broach, its not what they are built for,
My opinion , you would most likely get overload errors, and cause unnecessary
wear and stress on the machine.
all of the above advise is my rule of thumb, some may not agree with all of it,
but knock on wood, I have never had a service call on my VMC 40 ever these past
14 years, And I run it all the time, Its due for some ball screws and some TLC, but
aside from that it runs great
Wayne
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