X-Carve Moves the home position

[RodneyBeltz]

I am trying to cut a 24 x 24 Pc. When I home the machine to the bottom left corner it seems to start fine. After cutting for a few min it try’s to run off the top of the waste board. Then once I stop it goes back to the Home position but its about 12" above where it started. Need some Insight to what I am doing wrong. It cuts smaller pcs fine like 12 x 16 no issues.

[Rusty]

Sounds like you might be loosing some steps. Try checking your belt tension and v-wheels. You may also want to adjust your stepper pots on the gshield.

[DavidSohlstrom]

Sounds to me like he is loosing a lot of steps. 12" is a big change.

[RodneyBeltz]

Thanks I will check the belts when i get home. How do you check the pots.

[Rusty]

I’d take a look at @RobertA_Rieke tutorial, its pretty good and how I adjusted mine.

X-Carve Maintenance/Troubleshooting Videos - Add Your Own!

And, here’s the last video of mine this weekend. A guide to adjusting potentiometers, hopefully it’s not too confusing.

35 - Adjusting X-Carve Potentiometers - Manhattan Wood Project

[sketch42]

To reduce step loss on the Y-axis the POTs will need to be changed from the default position. To do this, just slightly adjust the Y potentiometer by turning it clockwise by a small amount until the Y-axis moves smoothly at rapid speeds (link when moving a long distance while Z is retracted on a large job)
Do not over-torque these pots - they are tiny and gentle and will break. The pots have 270 degrees of rotation.

See here for more detail:

Using grblShield

See also:

Setting the stepper motor current limit

The potentiometers on the gShield are setting the Vref (Voltage Reference) level on the TI stepper motor driver chips. This determines the current limit for the driver. You can measure this voltage at one of the potentiometer pins (see photo) and adjust it to obtain a given current limit. Use great care as the potentiometer pins are very close to other components and it is easy to short the pins together with your meter probe. Really bad things happen. The gShield (version 5) uses a 0.1 ohm cu…

[GregBuckwalter]

Wow, I just ran across this string and RobertA_Rieke’s video. I REALLY wish these pot tuning instructions were part of the setup instructions. I know I would have had a number of less headaches, if I’d done this during setup.

On another note, I’m also not sure why an actual squaring of the Y-axis motors isn’t part of the setup instructions. Perhaps I’m dense, but I’m missed that until I was doing a longer cut this weekend and noticed my Y-Axis wasn’t square to my wasteboard. Meaning the two Y motors were not square to my board. There are steps in the instructions on squaring Z and X, but Y was an easy adjustment using the wasteboard lines. Again maybe I’m just dense on that one, but I missed it and it would have been a easy steps to ensure the CNC is setup correctly. Just like the pot tunings. Suggested enhancement to setup instructions.