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General Mach Discussion / Re: Mirror probing
« on: March 31, 2019, 07:35:28 PM »
Hi Don,
I have a variation of the idea of either rotating the rifle under the probe or rotating the probe head.
My proposal is to have three probes (plunger micro switches, you know the cheap and cheerful ones!) mounted
on a plate which in turn mounts in the spindle.
To probe at or near the center line of the rifle you would monitor the output of the center (vertical probe)
and move it with Gcodes lke:
G31 Z-1 F4
If you are not familiar with probing G31 is the probe code. The move (in absence of X and Y coordinate data) is
downwards to Z=-1 inch. When a probe event is detected the movement stops and the motion controller reports
the XYZ position of the event.
This is very much the common use of the G31 probe command. It is not however the only way to use it.
for instance if you coded:
G31 Y-1 Z-1 F4
Then the motion would be in the YZ plane at 450 to vertical. If you monitored the probe parallel to
the direction of motion it would record a probe event as normal.
You can see where this is going. What I'm trying to do is arrive at a compromise that does not require either
rotating the rifle OR rotating the Probe head, because such rotation device would require extensive 'making'. This
alternative is an approximation to the rotating Probe head idea.
I will admit also that because Mach4 has the possibility of four separate probes the idea occurred to me to utilize that
ability. This could still be done in Mach3 but would require all three probe heads to be wired in parallel so that if any
one of them triggered a probe event and its associated data point would be recorded. That would work fine provided
that if for instance you are probing with a vertical movement (-Z direction) and either the right or left hand probe were
to strike some part of the rifle that would cause a trigger event erroneously.
Does the idea appeal?
Craig
I have a variation of the idea of either rotating the rifle under the probe or rotating the probe head.
My proposal is to have three probes (plunger micro switches, you know the cheap and cheerful ones!) mounted
on a plate which in turn mounts in the spindle.
To probe at or near the center line of the rifle you would monitor the output of the center (vertical probe)
and move it with Gcodes lke:
G31 Z-1 F4
If you are not familiar with probing G31 is the probe code. The move (in absence of X and Y coordinate data) is
downwards to Z=-1 inch. When a probe event is detected the movement stops and the motion controller reports
the XYZ position of the event.
This is very much the common use of the G31 probe command. It is not however the only way to use it.
for instance if you coded:
G31 Y-1 Z-1 F4
Then the motion would be in the YZ plane at 450 to vertical. If you monitored the probe parallel to
the direction of motion it would record a probe event as normal.
You can see where this is going. What I'm trying to do is arrive at a compromise that does not require either
rotating the rifle OR rotating the Probe head, because such rotation device would require extensive 'making'. This
alternative is an approximation to the rotating Probe head idea.
I will admit also that because Mach4 has the possibility of four separate probes the idea occurred to me to utilize that
ability. This could still be done in Mach3 but would require all three probe heads to be wired in parallel so that if any
one of them triggered a probe event and its associated data point would be recorded. That would work fine provided
that if for instance you are probing with a vertical movement (-Z direction) and either the right or left hand probe were
to strike some part of the rifle that would cause a trigger event erroneously.
Does the idea appeal?
Craig
) promoting Mach4 recently. The most recent developments Surface Map, script based THC