I am having severe under extrusion issues with my Ultimaker Original with heated bed and dual extruder upgrade and I don't find a reason for them. I bought the printer used and at the beginning it did not have these issues. I am having the under extrusion issue on both extruders. I am using original Ultimaker PLA, I have only one spool left, new material will arive tomorrow.
I would say it started since I upgraded to the latest firmware version but I am not sure if that's the reason or if it's just assuming it, because it was in the same time frame.
What did I do to find the problem:
- increased and decreased the hotend temperature (190°C to 210°C)
- check the tension of the extruder spring
- clean the knurled bolt
- changed knurled bolt between extruders
- change the bowden tube
- check the couplers
- check steps/mm settings - they are @836 steps/mm right now
While checking the couplers I found two washers (one on each hotend) between the wooden part and the coupler (see picture). I removed these because I could not find these in the assembly instructions.
Any suggestions how I should proceed?