how to calibrate your e step and flow rate to get better quality, more precision, and less clogs on your 3d printer. the code for e steps in your g code is:
M92 Exx ; ***SET NEW E STEP*** (xx factory value) (new value here)
replace the "xx" with your calculated e step values. insert the line of code after the G28 home code. link to the flow test cubes: https://www.thingiverse.com/thing:3220015