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Cnc4Newbie demon controller depth

So using ugs to zero with the triquetra touch plate. In easel everything moves as it should and even easels Z probe function works great. The bit starts where it should depth wise. Problem however is when I set 1/8th depth on 1/8 end mill. It maybe goes 1/16th. Or less. Any clue on why or where to start looking to solve it? Thank ya! Again initial start depth is correct and starts carving immediately without the bit just floating around.

When you jog the Z axis, she’s it move the correct distance?

I haven’t done the stepper calibration but since it goes down the correct amount to start the carve from zero I didn’t think that was the issue. I figured if the z stepper were off it would go down too far into the material or the opposite and hover over the material. So I don’t know

Are you measuring the depth after one pass?

Not specifically but I’m going to now. However if I had to guesstimate it’s around 1/32

I’m all for eyeballing things, but steps/mm calibration should probably be done with a measurement tool.

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Yea definitely agree with you and I will do that and post answers. However if that ISNT the deal, is there another course to go down?

If your gcode it’s good and it’s not the Z steps/mm, next I’d look at a possible mechanical issue which could range from lost steps on the Z to mechanical slop to something like interference from a dust shoe.
The more info you provide, the better.
What’s your $102 value?

What would be interesting is if you set a 1/8" section and right next to it a 1/4" section see if they are 1/8" different of only 1/16" different.

If they are 1/8" different then your z zero is not accurate in this area. Such error is common when the board in use has not been made parallel to the spindle plane and z zero is probed at a corner which is higher or lower (in this scenario 1/16" higher) than the section of the board that’s being carved… this is quite common on a copper board…
The top can be made parallel through one of a number of methods, with surfacing on the cnc being the most accurate… HOW TO FLATTEN CUPPED BOARDS WITH A CNC - Fix warped stock! - YouTube or Getting Uneven Carve Depths? Watch This Video... - YouTube

If they are off by 1/16" then this would be an indication that the calibration is off for steps/mm ($102 value) however if its the steps/mm that are off the your carve shouldn’t actually be touching the surface unless the probe thickness was entered incorrectly also SO for this being the more complex issue, I would bet that it’s the z zeroing being inaccurate mentioned ablove…