Z axis changing

My z axis changes 1" up or down when I start a tool path. I zero the z axis then load the file . I start that carve and find that my z axis has changed and is either cutting air or diving in to my work piece. I zero all axis manually. I am sure it is something I am doing wrong, just cant figure it out. it doesn’t happen every time. it 1" change when it happens. any help would be greatly appreciated.

check where the z datum is set in the file, material top or material bottom. match that with what you are zeroing on the physical workpiece.

1 Like

I’ve got the same problem, but I’ve tried zeroing before and after loading the program. Either way, I manually set the x and y, then manually lower the bit to set zero. I’ve gone thru the program line by line and cannot fine any errors.

After I’ve set x,y and z, which I do in the jogging page, I’ll go back to the program page. It shows all zero’s. Then, because I don’t like to start the program with the bit at zero, I’ll switch back to the jog page and raise z a hair. Then go back to the program page and start it running. More times than not, the spindle will raise up a random amount and fix that point to zero. I have to go back and reset z on the jogging page then go back to run the program. USUALLY, it now keeps the z value I just set.

Occasionally it does the reverse and sets z zero below the work piece. That causes BIG problems as in putting in a new blank.

This problem started all of a sudden and is getting worse every time. I’ve rebooted the machine, reset all coordinates, checked my g-code all to no avail. Very frustrating and costly. I just completed a lithophane (had to reset z at the beginning) and got the proper lithophane carved. Then when I went to engrave text at the top and bottom (unmilled area) the z zero value changed and the engraving bit drove staight thru the corian. 4 hours of work down the drain, not to mention the cost of the corian blank.

We don’t know enough to solve your problem.
Which CAM software are you using? Which controller? Tool setter?

I’m using Aspire 11.5, a Masso G3 Touch and no tool setter. I have an Elite Journeyman.

The only thing that comes to my mind is what 1F support posted. Is z0 on the material surface or machine bed?

It is normal that the spindle lifts after start.
The the controller will move the spindle to XY zero and the height will be defined by the Z-gap plus the Z1 clearance. Both number can be modified in the material setup page.

I would also check the Gap above/below the model, also in the material setup tab.

1 Like

l’ve opened a support ticket on this. All of the z settings in Aspire are appropriate. I understand that spindle lifts after start. The problem is sometimes it lifts appropriately, sometimes lifts to several inches above the z0 and then cuts air; sometimes drives down into the workpiece.

No way to tell which scenario is going to occur. The last project I did was a lithophane. The carving, which took about 4 hours went perfectly. Then when I went to engrave text on it, the TBN drove straight thru the completed lithophane, rendering it unusable. Same bit as was used for carving the photo image, same z0, same origin.

I provided support with 3 videos of cuts from a simple file they provided. First cut in the air, second cut went to .2 inches, which is what it was supposed to cut. Third cut went to .25 or .26 inches. Sent them the 3 videos and I’m waiting to hear back.

Mine has started doing the same thing after working perfectly for 1 1/2 years. What was your issue?

Hey Thomas, hey Darrell @wwcenturion,

sounds like the Z plunge issue. Do you have the old Original X-35/X-50 or pre-PRO Journeyman machine? If so you have a lack of strain relief at the connectors on the left X gantry foot and also you have the curly Z cable which is not made for permanent motion (so not suitable here). It can show internal cable breaks after approx. one year of use.

The successor PRO machines now have the 30 mm drag chains from the Elite machines, but still all connectors on PRO and Elite machines are made of those Molex/Amphenol connectors that are not made for use outside of a device (but just internally) and not for permanent motion, and still all PRO and Elite stepper cables are not shielded, so you can always think of EMI also.

See also

See also:

2 Likes

Thank you for this. It indeed turned out to be the Z axis cable gone bad. Not sure where, the connectors looked solid (encased in silicon), but somewhere the wire is bad. Replaced with another I had on hand and now everything is working good as new. Thanks again for looking out.

1 Like

My issue was that I have a tool setter, and I checked the box in the F1 screen that said only use it when I call for it.

What the controller was doing was then using the stored z for any tool that had been used before. Once I unchecked that box the issue went away. This was found by maso support by asking me just two questions. Apparently all this has been added to the frequently asked question area on one finity site.