M6 Remap - Something I don't understand - Now I'm stumped.

I created a M6 remap that allows me to use a combination of fixed length tool (length in tool table) and variable length tools (Zero length in TT).  In the remap code, if the tool length in the tool table is zero the tool goes to the tool sensor and gets measured.  I had this working and have used it to make parts.  However, the variable length tools are almost always drills and taps and most of the time the holes are through-holes.  So, I may have just never noticed the inaccuracy of variable tool measurement until I tried to use it for engraving bits.  The error is in the range of .020 to .050.  That is the problem I am chasing.   I am using QTDragon as my UI.  All of my fixed length tools work perfectly.  I have a separate GCode file that I use to measure the fixed length tools and populate the tool table value.

I added some (PRINT, ) statements to my m6remap.ngc file and it appears that the code gets executed twice each time it is called.  This is what I don't understand.  The "Pre M6" line in my main GCode file right before the T22 M6 line.  The Post M6 is right after the T22 M6 line.  It looks like it is calling the M6 remap code twice.  The first time the probe fails (#5070=0.000000) and the second time it succeeds (#5070=1.000000)
Thank You.
John

I think I might be seeing what is going on here. When looking at the full output of the trace file it appears that it may read through the GCode and execute the (PRINT, ) statements only and then when the GCode is actually run the (PRINT, ) statements execute again. I guess I am back to the original problem at hand.

John.

JohnnyCNC wrote:

I think I might be seeing what is going on here. When looking at the full output of the trace file it appears that it may read through the GCode and execute the (PRINT, ) statements only and then when the GCode is actually run the (PRINT, ) statements execute again. I guess I am back to the original problem at hand.

John.

When you load the file it will run through the gcode but not process any commands. IT will run the print statements. This is because the interpreter is not in task mode. When you run the file after it is loaded the interpreter will be in task mode and process all commands.

Thank you. That is what I was observing so I just started ignoring the values on the load pass.

I am completely stumped as to why the tool measurement in my M6 remap does not get a consistent measurement.  The GCode file that I run to measure my fixed-length tools and update the tool table repeats within 10ths so that rules out a flakey tool-setter.
If a tool has a zero length in the tool-table then it gets measure in the remap.  That measurement is varying as much as .188.

The tool_offset value is calculated with (-9.558231 + #5063).  What is really odd here is that tool_offset oscillates between -6.#### and -12.### inches even though the value in #5063 varies by approximately .188.   I'm pretty sure that I have a lot to learn here but I just haven't been able to crack it.

I could swear that this was working in the past but recently I was noticing that my variable length tool were not drilling/engraving to the correct depth.  That is what sent me off on this adventure.

These are the values I recorded over 7 test runs:

#5422=    -2.802416
#5063=    -2.802481
tool_offset=    -6.755750
    
#5422=    -2.615850
#5063=    -2.615785
tool_offset=    -12.174016
    
#5422=    -2.802483
#5063=    -2.802547
tool_offset=    -6.255684
    
#5422=    -2.615850
#5063=    -2.615785
tool_offset=    -12.174016
    
#5422=    -2.802766
#5063=    -2.802831
tool_offset=    -6.753400
    
#5422=    -2.616133
#5063=    -2.616068
tool_offset=    -12.174299
    
#5422=    -2.802999
#5063=    -2.803064
tool_offset=    -6.755167

---
This is the code I use to measure my fixed length tools and populate the tool table with the tool length.  Repeats within 10ths on an inch.

%
(measure_tool_inch v1.0)
G20
M5                 (Turn spindle off)
G43.1 Z0           (Tool length offset reset)
G92.1              (Cancel and reset G92 offsets)
G59.3              (Switch to G59.3 coordinate system)
G91                (Incremental mode)
G38.2 Z-.25 F20    (Measure Gross)
G1 Z.1 F40         (Move Z up .125 inch)
G38.2 Z-.15 F1     (Measure fine)
G10 L11 P#5400 Z0  (Update tool table)
G0 Z1              (Z up one inch)
G54                (switch to G54 coordinate system)
G92.1              (turn off G92 offsets and reset parameters 5211 - 5219 to zero.)
G49
G90                (Switch to absolute mode)
M2
%

--- This is my test code ---
%
(T22  D=0.25 CR=0. - ZMIN=-0.03 - FLAT END MILL)
G90 G94 G17 G91.1 G64 P0.001
G20                               (Inch units)
G53 G0 Z0.
G54
T22 M6
G0 X0.2988 Y-0.766
M30
%

--- This is my M6 remap. ---

(m6remap v1.3)
o<m6remap> sub

#2001=0     (Z up distance between probes)
#2002=0     (Fast probe feed rate)
#2003=0     (Slow probe feed rate)
#2004=0     (Z up feed rate.)

o300 if[#<_imperial>]
   #2001=.1    (Z up distance between probes)
   #2002=25    (Fast probe feed rate)
   #2003=1     (Slow probe feed rate)
   #2004=40    (Z up feed rate.)
o300 endif

o310 if[#<_metric>]
   #2001=2.5   (Z up distance between probes)
   #2002=635   (Fast probe feed rate)
   #2003=25    (Slow probe feed rate)
   #2004=1000  (Z up feed rate.)
o310 endif

#1702=-1                (Safe Z position for tool change)
#1900=#<_coord_system>  (Save current coordinate system.)
#<coordinate_system> = #5220
#<workspace_z> = #[5203 + [20* #5220]]
M5                                                                 (Turn spindle off)
G80                                                                (Cancel Canned cycles)
o500 if[#<_current_tool> EQ #<_selected_tool>]                     (Same tool as before so no need to do anything.)
   (This is tha same tool)
o500 else 
   (This is a different tool.)
   G90 G0                                                          (Absolute distance mode Rapid move)
   M6 T#<_selected_tool>
   G43                                                             (Enables tool length compensation.)

   o600 if[#5403 NE 0.00000]                                       (Use tool length from tool table)
      G10 L2 P#<coordinate_system> Z#[4000 + #<coordinate_system>] (Get touch-off - probe length for current coordinate system)
   o600 else (Measure tool to get offset)
      G53 X#<_ini[TOOLSENSOR]X_LOC> Y#<_ini[TOOLSENSOR]Y_LOC>      (Move to tool setter postion)
      G53 Z#<_ini[TOOLSENSOR]Z_PROBE_START>                        (Move Z  to safe height above tool setter to start probe)
      G43.1 Z0                                                     (Dynamic Tool Length Offset set to zero.)
      G92.1                                                        (Cancel and reset G92 offsets)
      G59.3                                                        (select coordinate system 9)
      G91                                                          (Incremental Mode)
      G38.2 Z#<_ini[TOOLSENSOR]Z_PROBE_DISTANCE> F#2002            (Measure Gross <_ini[TOOLSENSOR]Z_PROBE_DISTANCE>= -5.95)
      G1 Z#2001 F#2004                                             (Z up)
      #<probe_distance> = [-2*#2001]                               ([-2*#2001] = .2)
      G38.2 Z#<probe_distance> F#2003                              (Measure fine  probe_distance = .2)
      G4 P0.25 (wait for 0.25 seconds before proceeding)
      (PRINT,5422= #5422)
      (PRINT,5063= #5063)
      #<tool_offset> = [#4001 + #5063]
      (PRINT,tool_offset= #<tool_offset>)
      G10 L2 P#1 Z#<tool_offset>
      G4 P0.25 (wait for 0.25 seconds before proceeding)
      G1 Z.1 F40
      G90 G0                                                       (Absolute distance mode, Rapid move)
      G53 Z#1702                                                   (Z up to safe position)
   o600 endif

   (Restore orginal coordinate system. G54 to G59.2 only)
   o100 if[#1900 EQ 540]
      G54
   o100 endif
   o101 if[#1900 EQ 550]
      G55
   o101 endif
   o102 if[#1900 EQ 560]
      G56
   o102 endif
   o103 if[#1900 EQ 570]
      G57
   o103 endif
   o104 if[#1900 EQ 580]
      G58
   o104 endif
   o105 if[#1900 EQ 590]
      G59
   o105 endif
   o106 if[#1900 EQ 591]
      G59.1
   o106 endif
   o107 if[#1900 EQ 592]
      G59.2
   o107 endif
o500 endif
G92.1
o<m6remap> endsub
M2

Thank you for reviewing.
John