Tool and work offsets

For some reason if I run from line, it will execute a touchoff for every previous M6 that is in the Gcode. Is there any way around this?

No,this is a linuxcnc problem, because it does not realy support run from line.

[Also, the easiest way I've found to measure "block height" with the machine is to use a tool that has a Z offset in the tooltable and touch it off to the workpiece. I subtract the current absolute Z height (while the tool is toouching the workpiece) from the tooltable offset and that is the blockheight. Is there an easier way to do this rather than touching the table then touching the workpiece?

If you set it up like explained in the documentation, you only need to measure the hight from the surface of the workpiece to the table and enter that value. I use a digital depth caliper for that. It is connected through a BOBE virtual keyboard box to the computer. One button press on the caliper and the value is set?

Norbert

When using a vice it is difficult to use a direct measuring tool to easily measure the height of the workpiece. The base of the vise flanges out and the piece may not overhang. I suppose I can measure features on the vise before hand and just add the protruding face of the work. It's always easiest for me to just touch the too to the part.

you can change the complete behavior, just editing the change.ngc file.

Norbert

I have also been playing with the work offsets. I have a commercial machine. when I set my tools to the top of part I use a Mitutoyo 1" tool setter. I then set my work offset for Z to -1.000 that is what puts the tool at the top of the part. I rarely change this. In GMOCCAPY If I put 1.000 in the Z column of G54 work offset when I touch off my tools you add this number to the tool offset at the time of touch off. So if Z tool offset is -.500 you put -1.500 in the tool offset for this tool it should be -.500 the 1.000 work offset should be added at run time. This allows you to make changes to the part height at run time using the part offset without effecting any of your tool offsets. The same thing applies to touch off to a 123 block. I touch off my tools to the 123 block 2" plus 1 Inch for tool setter. I then I then touch off my Haimer to the 123 block 3". I can the touch off the top of my part add the difference to the Z in part offset and I am good to go. The tool heights never change they are always touched off to the 3" block. The Z work offset does not affect the tool touch off height or what is stored in the tool offset table. Is there a way to change this? The other thing is when I put -1.000 in the G54 Z location it subtracts it. Z is always negative. so a -1.000 work offset + a -1.246 tool offset should be -2.246 not -.246. I am using master.

Jim

newbynobi wrote: you can change the complete behavior, just editing the change.ngc file.

Norbert

Like I said, pretty bad with Gcode at the moment. Actually I went through the extra steps to get a good measurement from my table to the top of the fixed vice jaw, now I just add or subtract the height of the work in the vise from that static measurement.

I didn't get a chance to look at the change.ngc file, but I was also wondering if there is a way to alter the behavior of the probing routine when an M6 is requested on the same tool that is already in the spindle. FreeCAD puts an M6 in every operation. Without touch probing set up, an M6 on the same tool will raise the spindle and go back to work. With touch probing the M6 will cause it to probe even if the tool wasn't changed. This takes up a bit of time on a column mill because the tool length varies so much I have to keep the search speed low.

Is there a way to modify this behavior or would it be better to replace the M6 on the same tool with a G53 G0 Z0 or something like that?

Hi,

same issue here and i modfied the Change.ngc file. Documentation is on my Website (unfortunately in german). If you Need it in english, just let me now...

short description: i added an "if"-Operation checking if new tool is different to actual tool. (will upload the file later from home)

fraeserbruch.de/linuxcnc/gmoccapy-werkzeugmessung-optimiert

Another issue i am working on is this: if tool measurment is complete and the job is started, the spindle moves down above the TLS. i dont want this, because sometimes the TLS is higher than Z-Position in the Job =Y risk of rotating millbit crashing into TLS....
Greetings

Andreas