How about something along the lines of a magnet that keeps the probe in positon, but breaks away when the force gets too high? I haven't really worked it out in my head yet... just blurting out ideas.
Himmay? do you really have that much squirrelleyness with Mach? I haven't done more than jog my machine around and run some sample programs, but it seems to do what I tell it to do (right or wrong, that is.) If you have posted examples of this going chaotic, please guide me to them.
Matt,
Yes, Mach3 really IS that squirrelly. It will work perfectly for days, or weeks, at a time, then do something stupid. I've had it do such things as:
1) Spontaneously simply stop executing a g-code program right in the middle. No E-Stop, no Stop, no FeedHold. It simply stops doing anything.
2) Spontaneously turn off the spindle or coolant in the middle of running a program
3) Decide, as it has recently, that G4 delays will ALWAYS be in seconds, rather than milliseconds, regardless of the configuation setting
4) Decide to ignore jog commands. For example, right now, my Z and A axes will not jog after an E-Stop, until I've jogged X or Y.
5) Decide to ignore spindle or coolant on/off commands
6) CV still does NOT work correctly on 3-axis helical moves unless acceleration/velocity settings on all three axes are virtually identical.
7) So many other things, I can't even remember right now....
Probing is, and always has been, particularly flaky. Most of the time it works fine, but every once in a while, it decides to move the wrong axis, or move it in the wrong direction, or move multiple axes, or simply ignore the probe input entirely, or do the probe operation correctly, then move the wrong direction on the retract. Pretty much all of these stand a very high chance of breaking a rigid probe, as they have done to me countless times. Just last week I had yet another tool ruined, along with two touchplates, when Mach3 decided to ignore the probe input, and it simply drove the tool right through the touchplate and into the workpiece with several hundred pounds of force, stalling the quill servo.
Virtually all of the bugs I've witnessed over the years have, eventually, been proven to be actual bugs in either Mach3, or the SmoothStepper, or the communications, or lack thereof, between the two. And, most have been fixed, or at least reduced in frequency of occurrence. But, I'm still running on almost a one year old version of Mach3 and SS plug-in, as I've seen problems in the later releases. At least the version I use are a known quantity. Hopefully, Mach3 v4, once it's out and de-bugged, will become a more stable platform, but right now it's got a long ways to go before it can be considered robust.
If you search here and the Yahoo Mach3 forum, you will find dozens, if not hundreds, of posts I've made over the years reporting the problems I've seen. While many people tried to blame many of the problems on the very slow PC I was using for quite a while, not ONE problem was ever definitively pinned on the PC, and the vast majority were PROVEN to be actual Mach3 or SS bugs, and most have since been fixed. It works FAR better now than it did two years ago.
Regards,
Ray L.