Tool length offset reduction macro (Sinumeric 840D)

Hi,

We are using abrasive nylon brush to clean parts on the machine after machining.
We would require a macro of some sort to “shorten” the tool offset by 0.02mm every time program is run.
We tried “L_39 (0,0)” to do this, but it only writes the given value to wear.

Example: L_39 (-0.02,0) would write -0.02 in to “WEAR” section. If run again “WEAR” would stay the same -0.02, not -0.04.

Also, which parameter is used for the minimum tool length?

Example: If our tool is 150mm long, and minimum tool length can be 135mm.
When -0.02 is applied enough times tool length would reach 135mm and then give an alarm or a warning of a tool being too short.

Any help would be appreciated.

Hi McMaster
I think i can help you with what you need

If i understood everything right it should go like this

T10 D1
M6
G0 G90 G17 G94
G54
CYCLE800(1,"DMG",200000,57,0,0,0,0,0,0,0,0,0,1,,1)
HEIGHT_CORR(-0.02) ;MACRO PROGRAM I WROTE
...
...

Just make "HEIGHT_CORR.SPF" in user cycle directory on your machine and copy this below in it.
Hope this helps

PROC HEIGHT_CORR(REAL PAR1)
DEF REAL PAR2
PAR2=$P_TOOLNO
$TC_DP3[PAR2,1]=$TC_DP3[PAR2,1]+PAR1

IF $TC_DP3[PAR2,1]<=135 GOTOF ALARM1
GOTOF END

ALARM1:MSG("TOOL IS AT 135 MM LIMIT")
STOPRE
M00
GOTOB ALARM1

END:
M17

ello everyone,

I have a task at my new job that I need assistance with. Previously, I worked as a CNC CAM programmer, but I am facing a challenge because I lack experience in macro programming for the Sinumerik 840D. The requirement from our customer is to set a macro where the tool length is updated by about -0.005 or so, then return to the main program, execute it with the new length, and store the actual length of the tool after each execution. Additionally, there should be an option to set a minimum value for the tool. I would appreciate any ideas or suggestions you may have. Thank you.