Z axis touch off issues_2

Hi All my problems with Z axis touch continue. If I’m close to the machine within about a 6"x6" area it sort of works. It sets cut height a bit below the 0.060 I have it set for but that should work. If the job tries to cut further out of this range the cut height is set about 0.200, this is too high for a good cut. Am I missing something in the calibration or is there setting to correct this?
Also note that I have my probe offset for z axis at 4.8mm, if I don’t do this the torch dives into the work piece when cutting.
My table surface is within 0.006 level across the board.

Sorry for the poor quality. These are the first I’ve ever done.

Table level test.

Cut simulation.

First thing you need to do is lower your torch mount. The way you are now your operating at the lower limit of Z travel which results in very little spring pressure being exerted on touch off. The Z relies on this spring pressure for downward movement. Try to get things so the difference between Z home and the torch tip touching the work is maybe .750”-1.0”. This way the spring is well compressed.
How about a pic of your torch cable support set up and the cable loop?
What does a cut test look like with the stylus installed rather than the torch?

Hi Bob. My torch mount is already at the lowest position. there is exactly 1 7/16" from the torch tip to the work surface in the home position. My cable is pretty much self supporting, I tried some bungies I didn’t like that setup.
The simulation with the stylus is pretty much the same as with the torch.

Your mount can be lowered. Can plainly see that in your first video. Remove the shoe for the plasma torch. Unbolt the Z axis from the arm and use another set of holes to lower the entire Z axis on the arm. The spring compression state makes a big difference in probing.
With a straight head torch the power cable stiffness can be a battle. With a hand torch you have an automatic flex loop formed. You don’t easily get that with a straight torch. A pic of your torch cable support would help troubleshoot.

Agree with BobD reply in above post.

Wow, I never realized that there was a dovetail clamp back there. I lowered the mount down 1 screw hole, I hade to raise the dovetail up a bit to get the 3/4" to 1" clearance, torch to table in home position, it’s actually 7/8". I also reset my probe offset back to zero.
The torch is just riding the work surface now.
I did another video so that the torch cable can be seen.
new cut simulation

Did you recalibrate the Z axis?

So what do you mean by resetting your probe offset back to zero? Probe offset generally refers to what is determined by running calibration and is the difference between the stylus and torch centers.
If you set your cut height to zero it seems your new video shows things working right.
So now set your cut height to say .060”. Do a run, pause and measure the cut height. Adjust your height setting as needed to get .060”
Your torch cable support looks ok.

what do you mean by recalibrate Z.
Is it what Andrew did in the video ’ Step 1.5 Z Axis Calibration’
If so then yes I tried to play around with the stylus offset but eveything is so way off now I can’t even get it close.

Sorry Bob I meant to say stylus offset.

I’m just going run the calibration again for about the 8th time, maybe I screwed up the last one.

After talking to Andrew he determined that it was probably a faulty Z axis limit switch, he was right. He sent me a replacement switch, after I installed it my Z axis is now working perfectly.
Thanks Andrew, great support and service.

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