Well that's certainly a failure in design / programming by the manufacturer.
I'd have it so that when re-enabling Z the first and only thing it would be
able to do is rehome Z up so it knows where Z is. Even if the manual says the
operator has to power cycle and rehome everything after using Z disable, that's
just passing the buck on bad design.
Machinery should, wherever and whenever possible, be designed to make it
impossible for operator action to damage the machine using controls on it.
An all too common example is soft serve ice cream machines that have completely
independent freeze and stir functions. That makes it possible to engage freeze
without stir, then turn on stir and break things. A simple change in the switch
wiring makes that damage impossible to do, while leaving the ability to stir
without freeze, but *not* freeze without stir.
On Wednesday, August 8, 2018, 12:23:52 PM MDT, jeremy youngs
<[email protected]> wrote:
On Wed, Aug 8, 2018, 12:59 PM Todd Zuercher <[email protected]> wrote:
> If the behavior is anything like the Z inhibit button on all the Fanuc
> machines I've worked with it is a horribly dangerous device. On the Fanuc
> machines (modern newer ones with absolute encoders included) it is the
> equivalent of disconnecting the outputs of the stepgen and nothing else.
> When the button is released if the commanded Z position isn't the same as
> when it was pressed, the Z absolute position is shifted by the difference
> and can't be corrected without cycling the control power (rehoming doesn't
> even fix it). And since most of our Fanuc machines use tool change
> routines that include Z axis moves, tool changes can't be done with the Z
> inhibit active, pretty much making it completely useless.
>
> Mazaks have similar behavior when feed held and shifted in handle. When
> placed back in auto move it will start from where it last was in auto mode
> and not reference the handle move off , this was the source of my biggest
> screw up ever , I ran a criterion millionths boring head straight into a
> renishaw toolsetter , killing both of them with 1200 ipm rapid.
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users
