Extruders motors not turning

Other Hardware Motors, Mechanics, Power and CNC
1

Hi all, I am at a complete loss, My extruders on my latest five colour mixing printer will not turn, I am using a Mega 256 with Ramps 1.4 and three add on extruders together with Marlin firmware.
At power on all extruders are free turning, no power as are X Y and Z When I ask it to home all axes X Y and Z home perfectly then I heat the hot end to 200 degrees (PLA) minimum temp set to 105 degrees, and then try to extrude on any one of the five axes and all that happens is that extruder locks solid and will not move to extrude.
I have tried changing an extruder motor and cable onto the X Y or Z pins and the extruder motors all work fine as one would expect, I have swapped the extruder A4988 drivers onto X Y axes and relevant axis work fine, have checked all voltages on the A4988s and Vcc is 5V and Vmot is 12volt the trim pots are adjusted to1.2 Volts all the same as X Y and Z The add on drivers voltages are correct as well I have set pins.h commenting out the default servo pins and I set them as follows

#define E0_STEP_PIN 26
#define E0_DIR_PIN 28
#define E0_ENABLE_PIN 24

#define E1_STEP_PIN 36
#define E1_DIR_PIN 34
#define E1_ENABLE_PIN 30

#define E2_STEP_PIN 4
#define E2_DIR_PIN 40
#define E2_ENABLE_PIN 42

#define E3_STEP_PIN 5
#define E3_DIR_PIN 59
#define E3_ENABLE_PIN 64

#define E4_STEP_PIN 6
#define E4_DIR_PIN 66
#define E4_ENABLE_PIN 58

After doing all this I still cannot get the extruders to run can someone please help and point out What I have missed or done wrong.

2

Something is shifting/expanding due to the heat freezing the screw mechanically. You will have to find and fix that or replace it.

3

Very typical of plastic injection equipment! How are you sensing and controlling the heat? Are you keeping the temperature stable after the initial heat time?

AN additional thought: How do you clean the nozzles after use? I used low temp polyethelene on my injection molding machine way beck then.

4

Check (swap? replace?) temperature sensor. Smart machines stop parts from working to save the system.

Also, here is Creality's support videos...

5

Hi thanks for the quick reply, I have checked the resistance across the thermister and compared it to a new one both were very close at 1.3k and 1.4k at the ambient temperature and when working the temperature scale is rising and falling

6

The cables should be removable. Do you have access to another sensor (with cable) to replace the unit-under-test?

7

Hi thanks for you email I have replaced the whole thermistor and cable and still no movement

8

Hi thanks for your input the extruders are geared type and nothing is binding until an instruction to move is sent then the motor seams to receive some power to lock it.

9

Verify all cables to motors are seated. If your cables are long enough, cross-connect (x axis to y axis) the cables to see if the problem follows the cable or follows the motor.

1 Like
10

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.