Going Up? Z Axis will only go up

Just finished the build, completed testing the system and found the Z-Axis will only move upwards.

Problem: When i press the up or down button for the Z-Axis the Z-Axis will always move up.

Troubleshooting steps:

  • Checked Wiring: I thought i had messed up some of the wiring so i went back and double checked all connections. I found all of the connections were clean and secure.
  • Checked G-Shield to Arduino Connection: Reconnected the GShield to the Arduino

Same results after the first two troubleshooting steps.

  • Tested the Z-Axis Motor: Connected the Z-Axis Motor to the X-Axis connectors on the GShield and the X-Axis motor to the Z-Axis connectors on the GShield

After changing the connections the Z-Axis moved perfect, but the X-Axis would now only move in one direction.

Any thoughts? I am hoping i missed something.

Overview of my GShield:

Thanks for the help!!

just curious, is that a red wire going to the ground on your gShield power terminal?

Good question, I just double checked the connections and everything is connected correctly. I just had to adjust the cable so the cable markings would show up.

You direction pin from the arduino to the driver board for the z axis has a problem some where. Also check you config file to make sure Z direction is set to the correct pin.


I replaced the Arduino with a Uno I had already. Used Xloader to load the grbl_09i_xcarve hex.

I am getting the same results with the new Arduino.

GRBL Settings:

$0=10 (step pulse, usec)
$1=255 (step idle delay, msec)
$2=0 (step port invert mask:00000000)
$3=3 (dir port invert mask:00000011)
$4=0 (step enable invert, bool)
$5=0 (limit pins invert, bool)
$6=0 (probe pin invert, bool)
$10=3 (status report mask:00000011)
$11=0.020 (junction deviation, mm)
$12=0.002 (arc tolerance, mm)
$13=0 (report inches, bool)
$20=0 (soft limits, bool)
$21=0 (hard limits, bool)
$22=0 (homing cycle, bool)
$23=3 (homing dir invert mask:00000011)
$24=25.000 (homing feed, mm/min)
$25=750.000 (homing seek, mm/min)
$26=250 (homing debounce, msec)
$27=1.000 (homing pull-off, mm)
$100=40.000 (x, step/mm)
$101=40.000 (y, step/mm)
$102=188.947 (z, step/mm)
$110=8000.000 (x max rate, mm/min)
$111=8000.000 (y max rate, mm/min)
$112=500.000 (z max rate, mm/min)
$120=500.000 (x accel, mm/sec^2)
$121=500.000 (y accel, mm/sec^2)
$122=50.000 (z accel, mm/sec^2)
$130=290.000 (x max travel, mm)
$131=290.000 (y max travel, mm)
$132=100.000 (z max travel, mm)

Thank you,

After you swapped the X & Z axis motors and got the same results, I’d suspect the gShield having a problem.


I agree with @ScottWillis, seems like a gShield issue… other than testing and tweaking the amount of power to the Z-Axis with the pot I would contact help@ inventables dot com

(there is a too high and a too low for each of the pots… so test both ways and take it nice and slow and move in small increments)

Edit: See here for more detail except adjust the Z -

I am going to agree with you (@ScottWillis) and @sketch42, i feel the gShield is the issue.

All of the troubleshooting that i have done has yielded the same results.

I emailed help@inventables on Monday. Hoping to hear back from them soon.

did you try putting a meter on the direction pin yet?

I just stepped off to work, but when i get back tonight i will post the results i got.

When i connected the meter the first time it looked like i got the same readouts as when i connect the meter to the X and Y pins.

Are there any values i should be shooting for when i meter the direction pin?

Thank you,

<= 0.9 for one direction, >= 3V for the other

1 Like

I did some more research on the Digital Pins on the Ardunio, its been sometime sense I used the Uno i had already.

I tested all three direction pins and below are the results.

The output from all of the pins look correct, this includes the Z direction pin

I received a new gShield yesterday, and finally had time to install it today.

Everything is working great now.

Now i just have to remember the X-Carve is a bottom to top process vs the top to bottom process i have with the laser etchers i work with.

Thanks everyone for there help!