Mill jumping but LinuxCNC shows correct path

Hi all! I am new to LinuxCNC and new to CNC as a whole but making great strides! I have been able to get to this point without asking for help but it seems that time has passed.

I am trying to cut a 3d part.

I setup, home and touchoff the part. Start running the program and everything looks great for 3 complete passes of the code. Once it gets to the 4th pass .03 into the part the mill the jumps to a different spot on the material ruining the part. It jumps to the same spot each time but Axis shows the correct spot on the material.

I have tried this using 2 different tool paths generated by 2 different CAM apps (MeshCAM and HEEKS)

I have tried:
G92.1
G54
G49
running relative coordinate display

And I get the same behavior each time I attempt to cut this part.

Any help would be HUGE!!!

Many thanks,

The Wazz
Edit/Delete Message

Gcode attached. (Not letting me attach the file)

The issue starts somewhere around here:

X0.0039 Y2.4382 Z-0.0261
X0 Y2.4382 Z-0.0267
X0 Y2.4421 Z-0.0277
X0 Y2.5817 Z-0.0277
X5.5121 Y2.5817 Z-0.0277
X5.5121 Y2.7251 Z-0.0277
X0 Y2.7251 Z-0.0277
X0 Y2.8685 Z-0.0277
X5.5121 Y2.8685 Z-0.0277
G00 Z0.1987
X0 Y0
Z0.0509
G01 Z-0.0376 F3.93
X3.1318 Y0 Z-0.0376 F8.44
X3.1397 Y0 Z-0.0334
X3.1554 Y0 Z-0.0239
X3.1869 Y0 Z-0.0136
X3.2026 Y0 Z-0.0113
X3.2341 Y0 Z-0.0105
X3.899 Y0 Z-0.0112
X3.9541 Y0 Z-0.015
X3.9895 Y0 Z-0.0198
X4.0131 Y0 Z-0.0246
X4.0288 Y0 Z-0.0291
X4.0446 Y0 Z-0.0376
X5.5121 Y0 Z-0.0376
X5.5121 Y0.1434 Z-0.0376
X4.8354 Y0.1434 Z-0.0376
X4.8275 Y0.1434 Z-0.0329
X4.8197 Y0.1434 Z-0.029
X4.7921 Y0.1434 Z-0.0218
X4.7567 Y0.1434 Z-0.0163
X4.7174 Y0.1434 Z-0.0127
X4.678 Y0.1434 Z-0.011
X3.2774 Y0.1434 Z-0.0107
X3.2538 Y0.1434 Z-0.0126
X3.2341 Y0.1434 Z-0.0172
X3.2065 Y0.1434 Z-0.0295
X3.1947 Y0.1434 Z-0.0372




Preamble:
(Created with emc2b post processor 2013/01/02 09:18)
G64 P 0.0001 Q 0.0001
G54 (Select Relative Coordinate System)
(tool change to 1/4 inch HSS End Mill)
T1 M06
G17 G90 G20

I also was using MDI to run G92.1, G40, G49 and the like.

I have not read your tutorial but I will tonight. I have been RTM for the app that is where I tried "So if your lost what should you do" with no joy.

Thanks again!!!

OK cool I will try that and report back!

Thanks again!

Well my file size is 1695Kb so that may be it. If it exceeds the file size limit how do I work around that? Do I create a second file to complete?


ETA: I thought you meant that LinuxCNC had a file size of 1600Kb not the forum upload. I am just a little slow today...

Just to confirm ...
With the program running

the mill the jumps to a different spot on the material ruining the part.

After this happens if you use mdi to return to a know location say X0Y0 is it off by the amount of the "jump"?

Rick G

Have not tried to see. I will give it a go and report back.

Rick wrote:

Just to confirm ...
With the program running

the mill the jumps to a different spot on the material ruining the part.

After this happens if you use mdi to return to a know location say X0Y0 is it off by the amount of the "jump"?

Rick G

Yes it returns to the "jumped to" position as the new (wrong) X0Y0. Axis still shows the correct YX.

Thanks again for your time guys!

-Erick