To calibrate your extruder you first need to heat the hotend as most 3d printers have a minimum extrusion temperature, They will not extrude below that temperature this is usually around 170 degrees.
Next home the printer and raise your x gantry by 100mm this is A) so you don’t scratch your build plate and B) so you can see how the filament flows from the nozzle.
If you have filament loaded into the printer squeeze the extruder lever and pull the filament back so that it is just sitting in the entrance of the ptfe tube. Remove the ptfe tube from the coupling by pushing the white collar towards the extruder while pulling the ptfe tube towards the power supply (or right z axis profile if your power supply is under the printer).
Once you have the tube removed from the extruder feed the filament back in and cut flush with the white ring that you pushed in to remove the tube.
Now go to your screen and look for move then 10mm then E. Press the knob and turn it until 100mm is displayed and press the knob, At this point you should see the filament coming from the extruder. When the filament stops moving take a ruler and measure the filament that has been extruded if you get 100mm well done your printer extruder is calibrated from the factory and you are the lucky one.
If you find you only got 98mm your extruder is under extruding and you need to do some maths. In you screen under calibration > esteps > extruder you will have a number take a note of that number as you will need it for the calibration formula.
Calibration Formula
New Steps/mm = [100 / (measured filament length)] x (Current steps/mm)
To get your new steps per mm take 100 this is the amount of filament requested divided by the measured filament length in this case 98 then you multiply that number by your current esteps shown on your screen we will use an example of 415
100 / 98 * 415 = 423.469387755102
423.469387755102 is your new esteps, on your screen change your esteps to the new number and save.
now repeat the calibration process above and you should extrude exactly 100mm of filament, If not repeat the steps until you get exactly 100mm.
With your extruder pushing the right amount filament reconnect your ptfe tube squeeze the lever on the extruder and push the filament until it comes out of the nozzle. at this point you are good to print.
Direct drive extruder
For a direct drive extruder things are slightly different as you don’t have a ptfe tube to disconnect, In your case you would place a steel ruler where the filament enters the extruder and make 2 marks on the filament with a sharpie one at 100mm and one at 120mm, now extrude 100mm of filament once complete measure the distance from your extruder to the 120mm mark if you extruded 98mm you will have a measurement of 22mm and see both marks, if you extruded 102mm you will get a measurement of 18mm and you will only see one mark, if you extruded 100mm you will only just see he top of the 100mm mark at the extruder while the 120mm mark will be clearly visable, If you got 100mm you are good to go, if not then follow the calibration process above.
