Z-axis tricks

[orrs.welding.inc]

Hello group! New member but long time reader over last several years as I built my first candcnc based table with great success! Decided to try a new build with the gecko540 and different table design. I have my programs all working and calibrated (inkscape, sheetcam and mach3). I can import my test drawing of a 2 inch circle into Mach3, zero my x,y and z.. hit cycle start and it moves to start the cut & the z comes down. However, as soon as the torch is approximately 1 inch from my steel it changes direction and the z axis begins to go back up without touching off? I'm sure it's a simple setting in my software. Any insight would be awesome as I feel like I could be cutting again in no time!

[acourtjester]

I think there is a value in the Z command that limits the amount of travel down that is not enough and that is why this is happening. I think you hit the limit before the metal, one thing to change is the height of the torch at the start of the down movement in the g-code and the rapid clearance in SheetCam Job option I use 1". Plunge safety clearance may also have an effect.

[orrs.welding.inc]

Ok I'll check into that right now thanks!

[orrs.welding.inc]

I worked at adjusting the values in sheetcams
Job options and still continues to do the same movements. It will go to touch down, almost touch down and then retracts before the z micro switch hits

[acourtjester]

You can look at these 2 areas and see what the value is for the Z down movement. One is in the Post processor and the other is in a tap file, try editing your g-code (tap file) to find a value that works and then edit it in the post processor so it will be all of the new g-codes you plan.
Now if you are using a floating head switch the command may be a G28 and for a ohmic sensor it may be a G31 (probe being used).
Now at the start of an operation I always zero all the axis and then out the DROs for the X, Y, and Z, if Z is not zeroed and is to high that may cause your problem.

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