My Z drops more and more as the job progresses, but I do not appear to be having issues in the X or Y direction. I cut out cam clamps and I suppose if I was losing steps in the X or Y that the cuts wouldn’t line up, but they did. Last week I noticed I had about 1mm play in my router shaft, I replaced that today with a Makita. Stepper voltage was 1.21 on the lowest, and 1.27 on the highest. Motors are running about 90*F on the Z axis. I made the gcode with Aspire and Estlcam with the same results, the more the jobs goes on, the more the z drops. I have read every “losing Z steps” topic i can find, but I feel like I’m missing something obvious and can’t seem to put my finger on it. I am adding a picture to show the drop, and I will include the yaml file if someone wants to see if they see anything there.(had to change it to a gcode file to upload it btw)
I will include the gcode for the small test file if anyone wants to look at, or run it to see if they see anything. I ran grbl on a arduino with a CNC hat on the LR2 and I didnt have this issue, I am sure its mechanical, but I just don’t see anything binding that would cause missing steps. Also, just to make sure I’d like to know what everyone is using to lube the lead screws?
VTest 60_ VBit.gcode (206.9 KB)
No lube on the lead screws will cause it to miss steps for sure. Super lube that comes in the kit from Ryan is the best thing for it
I have a tube of it but this:
Lubing the lead screws and making sure the grub screws are tight with one on the flat part of the shaft. Those are the most common issues.
I was losing steps on z raises, I lowered the max rate per mm to 800 and that cured it. This is on a lr4
What’s your controller? That can play a role as well.
Thanks for all the replies fellas! I will relube the lead screws later today to give it another go, I am re hoping I just didnt lube well (or at all) during the build. I am running the jackpot controller, and I believe i already dropped the max rate for Z to 600. Here is my yaml file, but I couldn’t figure out how to add a txt file, so I changed it to gcode for uploading purposes.
config.yaml.gcode (7.0 KB)
I found this today when I was going through some boxes I packed up. I did
spray some lube on the lead screws when I noticed I had a problem, but it wasn’t as good as this stuff. I feel like a huge dumb a$$.
I appreciate the patience fellas.
No need for that at all! The rest of us know this is important because we have all had the same issues! Glad you came here to ask!!
When a wise man does not understand, he says: “I do not understand.” The fool and the uncultured are ashamed of their ignorance. They remain silent when a question could bring them wisdom.
— [Frank Herbert]
You’ve got the date wrong, it should say 2025! Get your guns! 
That is very nice
Are you sure it isn’t the bit slipping down in the collet?
I can’t believe this topic came up now, my last 4 jobs did the exact same thing!! I never had a problem with it before 2 weeks ago. The cuts just keep getting deeper and deeper as the job gets further into the engraving.
Thanks Jonathon for the suggestion, I’ll try it today!
Thanks DJ for bringing it up.
Yep. My Z loss has almost always been the bit slipping in the collet.
Yes, it ended up being my lack of lubrication on the lead screws. Lesson learned, I will make sure to keep an eye on that in the future!