# Check that Z-depth! It matters **URL:** \ **Category:** 💥 Amazing fail\ **Created:** [November 6, 2024, 2:01pm UTC](https://forum.sienci.com/t/check-that-z-depth-it-matters/14414 "2024-11-06T14:01:17Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![JamesORear](https://forum.sienci.com/user_avatar/forum.sienci.com/jamesorear/32/8423_2.png) [@JamesORear](https://forum.sienci.com/u/JamesORear)\ **Post date:** [November 6, 2024, 2:01pm UTC](https://forum.sienci.com/t/check-that-z-depth-it-matters/14414/1 "2024-11-06T14:01:17Z")
This project had two pocketing operations designed to be .250 deep, seems it was actually making them .500 deep so transiting between the operations the desired .200 above the workpiece was actually .050 below. Looks like we’ll be testing our repair skills. ![IMG_0438](https://forum.sienci.com/uploads/default/original/2X/a/a3fdb1d8c0cfaec696cfa2079ef1a7c825309f02.jpeg) G-code checks out ok so possibly a wrong tool height setting or machine losing Z? Can’t pin it to anything for sure. Words were said, tears may have been shed. James Dayton, Ohio ---
**Author:** ![\_Michael](https://forum.sienci.com/user_avatar/forum.sienci.com/_michael/32/2962_2.png) [@\_Michael](https://forum.sienci.com/u/_Michael)\ **Post date:** [November 6, 2024, 5:33pm UTC](https://forum.sienci.com/t/check-that-z-depth-it-matters/14414/2 "2024-11-06T17:33:13Z")
Welcome to the group James! Just a thought, but did you have a reliable place to reset the Z zero after the tool change? I know on some projects, where you mill the whole top surface, you don’t have the original spot to set Z zero again. This applies if your using a touch block or the paper method with Z zero at material surface. It’s one of the reasons that I prefer to set Z zero to the spoil board surface. Granted it does take some time to get used to Z zero being at the bottom of the material, but it also allows me to make precise through cuts that barely scratch my spoil board. I see from your other post that you have experience with large machines, but my thinking is those things are probably automated with big machines. ---
**Author:** ![JamesORear](https://forum.sienci.com/user_avatar/forum.sienci.com/jamesorear/32/8423_2.png) [@JamesORear](https://forum.sienci.com/u/JamesORear)\ **Post date:** [November 6, 2024, 5:46pm UTC](https://forum.sienci.com/t/check-that-z-depth-it-matters/14414/3 "2024-11-06T17:46:04Z")
I usually use the touchplate to set XYZ and project start and paper to set Z after a tool change. That’s how we do it on the machines we use in the guitar lab (an old Forrest Industries gantry mill). All the HAAS machines in the metal shop use toolsetters and Renishaw probes. I’m contemplating using your method soon. I have an enclosure that I’ll be building soon that changes my table and that seemed like a good time to start a new habit. Thanks for the reply. ---
**Author:** ![\_Michael](https://forum.sienci.com/user_avatar/forum.sienci.com/_michael/32/2962_2.png) [@\_Michael](https://forum.sienci.com/u/_Michael)\ **Post date:** [November 6, 2024, 6:01pm UTC](https://forum.sienci.com/t/check-that-z-depth-it-matters/14414/4 "2024-11-06T18:01:02Z")
If you do switch to Z zero at spoil board this other post of mine might be useful. > [@Permanent Z only probe](https://forum.sienci.com/t/permanent-z-only-probe/12182): > > I do most of my milling with Z zero set to the spoil board surface and I had an idea of how to make that workflow a little easier for me. I had an old Z only probe block that I think came with my first CNC, a Chinese 3018, and I wanted to mount it somewhere to use kind of like a Shapeoko BitSetter. Here’s what I came up with. As you can see from the photos the block came apart and I was able to make a nice snug pocket for it to be pressed into. I tested on scrap MDF pr… ---
**Author:** ![JamesORear](https://forum.sienci.com/user_avatar/forum.sienci.com/jamesorear/32/8423_2.png) [@JamesORear](https://forum.sienci.com/u/JamesORear)\ **Post date:** [November 6, 2024, 7:40pm UTC](https://forum.sienci.com/t/check-that-z-depth-it-matters/14414/5 "2024-11-06T19:40:08Z")
I’ll check it out. Thanks again.