You may want to try some dry run tests without filament in order to make sure that the left extruder stepper motor & motor driver are still in working condition:
- Heat up left nozzle
- Remove filament from left extruder
- Connect SV04 via USB & enter following commands in Printrun/Pronterface console window line by line (alternatively put instructions in several text files & name them sequentially “#.gcode” & run them in sequence). The comments (after “;”) don’t need to be entered:
M83 ; set extrusion to relative
T0 ; select left extruder
G0 Z20 F800 ; raise extruder
M83 ; set extrusion to relative
G92 E0 ; reset left extruder
G1 F500 E100 ; test left extruder - 4" slowly forward
G1 F500 E-100 ; test left extruder - 4" slowly backwards
G1 F1500 E100 ; test left extruder - 4" medium speed forward
G1 F1500 E-100 ; test left extruder - 4" medium speed backwards
G1 F2500 E100 ; test left extruder - 4" fast speed forward
G1 F2500 E-100 ; test left extruder - 4" fast speed backwards
G1 F3500 E100 ; test left extruder - 4" v fast speed forward
G1 F3500 E-100 ; test left extruder - 4" v fast speed backwards
G92 E0 ; reset left extruder
In case the stuttering occurs repeatably:
You could try to change the X- & E-connectors on the left breakout board located at the left backside of the gantry. Then repeat the tests above, but exchange “E” with “X” ito address the extruder motor. If that test runs successful there is a problem with the left extruder driver. This might be solved by adjusting the motor current on the motherboard trim potentiometer “E1”.
If the test still fails you can change the X- & E-connectors back. Most likely the problem is located in the stepper motor or the extruder mechanics. You’ll need to dismantle the extruder & look for mechanical obstructions. Try to remove the extruder wheel and re-run the test sequence again. If the test runs successful try to assemble the extruder & try again. If thetest still fails it is highly likely that your SV04 needs a new extruder. stepper motor.
