The problems could be a few things or just one of these things:
- Nozzles - Personally I would just stick with the 0.4mm brass ones, tried the hardened steel and had problems. Going slightly smaller may give you a finer print but takes longer. I also go for nozzles that are about 45 deg angle not the real shallow ones.
- Heater Cartridge - you may have an issue with the heater cartridge / sensor... and when starts to failure can be a little eractic and consistent heat is important.
- Teflon Feeder Tube - I have noticed is the feeder tube after time suffers wear internally and starts to grab the plastic that feeds through it and can cause stalls in the plastic feed and snapping of the feeding material. I now replace the Teflon tube after about 6 rolls and also give a quick squirt of silicon spray after each new roll of plastic installed inside the teflon tube outside away from anything and this ensures a nice material feed. The silcon burns off in the 200 degree heat through the nozzle.
- Rafting - Lastly for years I never used the raft feature and use to have average prints due to the base layer lifting etc, and since the first layer is so critical for all printers especially on the older makerbots which had no bed levelling early days. Now with using the rafting, my prints have improved as it also tends to take into account slight bed levelling issues.
All that said I only use the printer for proof of concept so does not get a huge workout like it use to.
hope that helps
