I own a Qidi X-Pro that uses a dual extruder. I just spent the last 45 minutes trying to print, over and over, a simple model I had printed before. I'm using ABS with a glue stick. The ABS is fed through the left extruder while PLA is fed through the right. I had previously printed a different model and had finished it. I was now attempting to print a different model with the left extruder and ABS.
The ABS print would almost fail immediately with the filament catching on other parts of the model. Then, I realized that a small piece of PLA was still exposed on the right extruder and it would catch the model as I was printing with ABS.
Is there a recommended way to ensure that this does not happen in the future? What nozzle 'clean up', if any, should I perform after printing?