G'day Rich
This is why I asked the question, Maybe somebody could steer me into a different direction. The shear pins is what I came up with from two sources, basically its based around a concept that works on firstly my Rotary-hoe, on the tines is an aluminium shear pin that drives them round, if you try to push the hoe to hard or deep in one action the pin would shear and major damage to the machine reverted.
I don’t know enough about Servos or the programming to put in something that stops when a certain figure is reached, amp draw ect, nothing in the manuals or setup relate to it.
I look at it as simple insurance on the machine, a given sacrificial part is way easier and cheaper to replace than a complete spindle or damaged to a quick change tool post ECT.
Maybe there is no such thing. I do know, another thing I noticed was the Bridgeport mill uses a plastic key-way on the spindle and this I assume is for the same reason.
Thanks for the reply.