Mini Gerbil debugging – movement

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Symptom DetailLikely causes and their solutions (in recommended sequence)
One of the axes is compressed, elongated, or doesn’t move at allLightburn rotary mode has been left on for that axis…. cancel Lightburn rotary mode
No movement at all!The large 4 pin plug into the Mini Gerbil must supply 24V and ground to move the motors.  Check the plug very carefully to ensure contact is being made.  Check wiring.

Stepsticks need to be replaced – use A4988 stepsticks
Movement on one axis onlyFailed stepstick. To confirm, swap stepsticks, and if proven, replace the failed stepstick.
Job movement in wrong direction (although homing is in right direction)Mini Gerbil settings should be checked – see https://awesome.tech/what-are-settings/

Lightburn (or other software) home position incorrectly set.  See https://awesome.tech/limit-switches-and-homing/

User has non-standard home position.  For inexperienced user, Awesome.Tech very strongly recommend using standard home position, see https://awesome.tech/limit-switches-and-homing/
Both job movement and homing are in wrong directionIf Y axis moves in incorrect direction, remove Y axis plug and rotate 180’ before reinserting
Making grinding sound while moving (prior to hitting end of gantry range), movement on one or more axes unsuccessful. Difficulty of moving laser head also occurs with K40 powered off completely (at wall). Adjust the K40’s belt tension, see your K40’s instruction manual

The stepsticks need to be adjusted for a higher current, see https://awesome.tech/adjusting-stepsticks/
Laser head is difficult to move by hand between jobsThis is designed intentionally, to stop the laser losing position between movement.  If necessary, the user can disable via macros in Lightburn.
Movement is poor, slow, jerky, limited or inconsistentCheck for mechanical issues such as incorrect belt tension or obstructions

Other appliances/devices on same power circuit as K40 & Mini Gerbil causing interference.  Examples: soldering irons, pumps, motors, etc Remove other devices from same circuit and test.

Mini Gerbil is used with a USB hub, especially one shared with other peripherals like a USB camera. Plug Mini Gerbil and other USB devices into the PC directly, not via a common hub.

Mini Gerbil settings should be checked – see https://awesome.tech/what-are-settings/

The stepsticks need to be adjusted for a higher current, see https://awesome.tech/adjusting-stepsticks/

Lightburn (or other software) home position incorrectly set.  See https://awesome.tech/limit-switches-and-homing/

User has setup a non-standard home position.  See https://awesome.tech/limit-switches-and-homing/

Stepsticks need to be replaced – use A4988 stepsticks
Making grinding sound while moving, movement on one or more axes unsuccessfulSwap stepsticks to debug movement.  
Sound heard from stepper motors even when no movementIt is normal for a slight whine to emit from the stepper motors.  This is because they’re energised to stop inadvertant movement, which will result in loss of position.
Grinding sounds occurs when attempting to move at high speed, but slow speed movement usually ok. Movement on one or more axes unsuccessfulCheck belt tension and for mechanical obstructions.  If problem remains, the contact us for instructions on changing stepstick current.
Movement stops part way through jobPC is going into sleep mode during operation.  Change PC settings.

Avoid running a laptop on battery power as this typically forces sleep mode.

PC USB system is going into sleep mode (note: this may not be visible to the user) Review PC settings https://apteryx.zendesk.com/hc/en-us/articles/360041367673-Disable-USB-Power-Management-Selective-Suspension

The particular file being engraved has curvatures that are incompatible with current GRBL ‘arc tolerance’ settings.  The Mini Gerbil comes with $12=0.002 as a default settings (see what are $ settings), so try tweaking this value to enable your image to be engraved. According to GRBL documentation (https://github.com/grbl/grbl/wiki/Configuring-Grbl-v0.9) Lower values give higher precision but may lead to performance issues by overloading Grbl with too many tiny lines. While, higher values traces to a lower precision, but can speed up arc performance since Grbl has fewer lines to deal with.

Faulty K40 grounding. See https://awesome.tech/k40-laser-grounding-instructions/
Movement as expected until laser turns on, then movement stops workingAs the K40’s power supply warms up it loses efficiency, and provides less power than needed. It’s time to replace your K40’s power supply.

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