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AndrewMawson
20-11-2016, 12:11 PM
I'm re- building a CNC Plasma table, not too bad for one someone has home built, but all the limit switches are mounted so that if there is over travel they will be squashed and destroyed !

Is it just me or does anyone else consider this bad practise?


19673


To my way of thinking, there should be a mechanical hard stop, possibly with a buffer, to limit travel and the limit switch should operate in such a way that it is contacted BEFORE the mechanical stop, and can physically be passed but electrically stops the drive system.

I'll attempt a re-engineer, but space is at a premium, especially on the gantry and Z axis, as no provision was designed in.

magicniner
20-11-2016, 12:15 PM
The limit switch on the Z axis of my benchtop mill has an adjustable set screw with locking nut as the physical stop, it is adjusted so that the limit/home switch acts before the stop and so the switch can't be squashed,

- Nick

JAZZCNC
20-11-2016, 12:51 PM
Yep that's poor design.

Better way is to make so Switch rides with the axis and rides over target ramp at each end. Less wires and switches to wrong and easy to setup.