On Tue, 15 Nov 2011 11:18:05 -0500, "Existential Angst"
wrote:

wrote in message
.. .
On Mon, 14 Nov 2011 23:38:13 -0500, "Existential Angst"
wrote:

wrote in message
...
I posted a while back that I might be buying a Fadal mill and running
it from a phase converter.

Don't use a ****ty out-of-the-box converter (even name brand), as they use
start caps that are never switched out, causing a wild leg that can be 30
V
over line V.

Separate the start caps from the running caps, which will be lower value
caps between both L1-L3, and L2-L3 (L1-L2 = line).

Also make sure the voltage taps on the Fadal are set for your local
voltage.


Well, I'm buying it. I'll write the check tomorrow.

What year, whadja pay?? What's yer location?

It's a model VMC-15 and has rigid tapping so I guess I'll
need that parameter changing info. Also, just what is the advantage of
rigid tapping over tapping heads?

There are *complete* online manuals, good qual. pdf's, I think from MAG.
*Identical* to the hard copy, ceptin now you can search'em. Free.

Tapping heads on a drill press? Their advantage is torque control, for
less
breakage.
Don't know much about other tap methods on VMC's.

But the rigid tapping is fast, clean, accurate, you'll be spoilt forever.
Also, I believe rigid tapping can handle roll taps better, which I now use
on alum almost all the time.
I'm rigid tapping as we speak.

Post to alt.machines.cnc (what's left of it), and also the
PrecisionMachinist forum, which has forums in various categories. No
Fadal
forum per se (iirc), but lots of fadal users there.
Year 1996, $18,500, comes with4th axis,

Hopefully low hours on the machine, but hard to tell.
The 4th axis is Da Bomb. Mine is very heavy (on a fadal 3016), so I keep it
permanently hoisted inside the cabinet on a winch, so mounting it is easier
for me by myself than for two people with all kinds of pneumatic tables in a
trad'l shop.


Whidbey Island WA. The phase
converter I'm runing is a good one that has proven itself for years
running CNC machines.

Well, check the generated leg. If it's 20+ volts above line, then you've
just been lucking out, and should separate the start caps from the run caps,
and tune the run caps.


How is rigid tapping faster? Do you program the
machine to back out faster than going in?

Hmmm, I don't, but I'll have to check the retract thing out. I meant to
years ago, never got around to it. Or I did, and it wasn't supported. I'll
check again.

Overall, it's faster cuz you just program in spot, drill, tap with one hole
pattern in a subroutine, and all that tnik said -- peck tapping, in essence.
And, if you want to get real sophisticated, thread cutting, which these
fadals don't support as canned cycles, so you'd have to use software or
program your own cycles, as the machine will helically interpolate, if it
has the CS-88 controller.

As far as form taps go, I've
never had a problem with them being used in tapping heads.

Well, they require higher torques, and the fadal should be able to handle up
to mebbe 3/4" with not much trouble.
The phase converter voltages are very close. Fanuc controls,
especially the older ones, are quite sensitive to over or under
voltages on one leg. The machine is in a friend's shop now. He has to
sell the machine so I'm buying it. Today I was running a job with both
a pipe tap and thread mill. So I guess it must have the right kind of
control for thread milling. And the 4th axis is really nice. But at
165 lbs I'll be using an engine hoist to put it in and out.
Eric