Geeetech A30 Building Instructions page 19

Firmware settings are correct, including: axis movement speeds and acceleration;
temperature control; end-stops; motor directions.
The point regarding the extruder step rate is vital. Too much extrusion will result in
blobs and other imperfections in the print, while too little extrusion will result in gaps and
poor inter-layer adhesion.
For how to set up the printer, please refer to the user manual.
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