On 2010-11-27, Wes wrote:
Pete Keillor wrote:

Controlling the spindle is slightly more important, as it lets me
change tools. But, I suppose, I could turn off the spindle manually.

Personally, I would be leery of changing a tool manually under a
program stop. I'd much prefer to turn it off manually. I wouldn't
want my hands on the spindle without being certain it wasn't going to
move. Or are you using a tool changer?

I like your thinking. On enclosed machines the doors have interlock switches but these
are open machines. I'd really hate to be holding on to a cutter or a draw bar wrench and
have the spindle power up.

Well ... at least Iggy's machine has a quick-change spindle
which holds NTMB 30 tool holders. No drawbar, Just slap the tool into
the spindle and use a notch spanner wrench to tighten (and to loosen
when removing a tool prior to installing the new one). And while using
the wrench, your other hand is leaning on the spindle brake. I don't
know whether the spindle motor can override the brake.

But add a switch in series with the run/stop command line to the
spindle's VFD, and set it up so removal of the wrench will disable the
spindle motor until the wrench is returned to its storage pocket.

IIRC, with the original BOSS-3 Bridgeport -- the stop for a tool
change lights a red light in a pushbutton deep in a guard, and you have
to push that button to re-enable the spindle. (This was with a
forward/reverse contactor, not a VFD back in those days. :-)

I've grown to hate touch screens overloaded with buttons. Some are too sensitive and the
action you think you are selecting may not be what you get. This with a non cnc
appplication with a lot of lots of things that can get tripped in manual.

:-)

Enjoy,
DoN.

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