Problem: Hot end works great with most filaments but with at least two specific filaments it holds the target temp (210) for the first layer or two then drops to 180-190 for the rest of the print.
Solution: Tuned fan speed down to 30-60% rather than 100%
Background: I’ve had my TAZ6 for a couple years now and use it routinely for producing large numbers of small objects (basically prop coins) that I then sell. I use 7 or 8 different colors of filament [all PLA, most from the same supplier, stored in the same way] to make the different types of coins. A few months ago I switched from the stock printhead to an Aerostruder and at the same time I switched from Cura 21.04 to Cura-Lulzbot 3.6.13.
For a month or two everything worked great. Then I noticed prints using the White Silk (Filaments.ca EcoTough brand) filament were jamming a few layers in and after watching the prints I realized that after the first layer or two the temp was dropping from the programmed 205 to 180-190. That was leading to the filament grinding which lead to the jam. When I couldn’t resolve the issue at the time I figured it must just be something with that particular species of filament (changing the spool hasn’t affected the issue). Every other color of filament was printing normally until a few days when a second color of filament (Ziro Twinkling Red) started causing the same issue.
- I’ve double checked the gcode on each model and can’t find any errors
- Any model/gcode I print with another filament works fine, but any model/gcode printed with one of these two filaments can’t hold the temp
- I already checked my extruder’s serial code against the Service Bulletin for Aerostruder printheads in Feb2018
- Without a print job the print head has no problem reaching and holding it’s max temp (290)
- Since I only use PLA my temperature parameters don’t change much from job to job, typically 205 or 215 for the extruder and 60 for the head bed
- Adjusting the temp in the gcode or manually during a print has no effect on the actual temp
This all seems to suggest some gremlin in the hardware or firmware somewhere but I can’t understand why would be specific to a particular species of filament in that case. I might be able to replace these particular colors with some other brand but if the problem spreads to other filaments that becomes more and more problematic.