FFCP Dual Extruding huge jamming issue. Advice requested..

[huntleybill]

I have been trying to print the traffic cone with dual extrusion and am having issues with the left extruder. I am using black PLA. The process will start fine but when it gets to about 10%, the extruder jams. It doesn’t jam at the nozzle but at the top of the barrel. I then have to remove the nozzle and PTFE tube, take out the stepper motor and extruder block, let the heater cool down, then snap out the jammed piece. I then reassemble everything, load the filament, and extrude some material to make sure it is ok. It extrudes during the loading process quite well. I then restart the print and at about 10%, it stops extruding again. This only happens to the left extruder. The right extruder does not have any issues.

I have tried the following variations but none of these fixed the problem.

• Made sure filament feed roll is not binding.
• Checked and re-checked that the bed is leveled and the extruder is not too close to the glass.
• Raised the temp to 225
• Lowered the temp to 200
• Slowed the speed to about 40%

I tried slicing the model using ReplicatorG, Flashprint, and S3D. Didn’t make any difference.

Curious thing is when I use ONLY the left extruder to print a model (single extrusion), it prints the whole model with no jamming. Using the same filament with the same settings.(last picture of tugboat).

In the attached pictures I am attempting to show you where the filament is jammed. You may have to zoom in. Not sure if these are helpful or not.
How do I prevent this from happening???
Thank you for your time.

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