Prusa i3 MK2 3D printer problems

[urbite]

I was part of the DMS workshop where the group purchases the Prusa and built them together in a workshop.

Prusa i3 MK2 3D Printer Build Workshop

The 3D Printer Build Workshop went well! Thank everyone that bought a kit and showed up. I know it was a very long day but I hope everyone got a lot of enjoyment out of it and have a good reliable printer. [image] I want to use this thread to let everyone show what they’ve printed with their prusa kits so far, as well as ask questions or troubleshooting. I have been having very good results so far, with minimal issues. [image] [image]

I have successfully printed several things in PLA, but my printer has been idle for about a year. Needing some knobs for a guitar pedal, I fired it up after making the model in Fusion 360. The printing didn’t go near as smoothly this time as I remember in the past.

The initial problem was that the 1st layer wouldn’t stick, so I upgraded the firmware and used the first layer Z adjust. This fixed the problem for the most part.

The next issue was that sometimes when starting a print, no material was coming out of the extruder. When I tried to unload the filament it wouldn’t come out because it had a ‘fat’ end that apparently wouldn’t feed into the extruder. This issue also occurred with ABS and PETG (more on this later). I adjusted the filament feeder tension screws by waiting until the springs were just contacted, then adding another turn or so. The pic below shows the fattened filament end. I don’t remember this happening with initial and subsequent printer use.
Does anyone have any suggestions for how to remedy this? Should I completely remove the extruder and clean it?

One thing that may be contributing is that I haven’t been keeping my filament in vacuum pack with desiccant, as I’ve seen recommended. I have the vacuum bag, pump, and desiccant, but got lazy the last time I made a print and didn’t re-store it correctly. However, the PETG had never been opened and it appeared to be vacuum sealed. I don’t know if filament that has absorbed moisture has issues similar to that with stick welding rods. Anyone have any knowledge on this?

Lastly, my PETG prints didn’t turn out well at all. Printed PETC parts didn’t stick well and small things (such as a guitar pedal mini sliding pot knob) just ended up being a blob.

All of the filament being used is from MicroCenter, with the exception of the PLA that came with the printer. Is it coincidence that my PLA prints have the least problems?

Without committing to do a full upgrade from a i3 MK2 to i3 MK3, what changes can I make so that this printer will work better. New extruder? What kind? Other reasonably priced upgrade recommendations?

I assume that the Polyprinters don’t suffer these issues - or at least not to this degree.

[JRay]

Your extruder gear looks like its slipping. You can see the plastic fouling the teeth. Take a look at your filament. It probably looks like it’s been chewed up at the extruder.

Are you able to load at all? Step one in loading is to cut the filament at an angle with a pair of dikes. Gives a nice sharp edge to lead into the hole. Once loaded, can you a bunch of filament through the extruder? If not, I would suggest a nozzle cleaning. You might google “atomic pull” before you start ripping the whole thing apart, as that may fix it.

Just my thoughts.

[Brian]

Is it coincidence that my PLA prints have the least problems?

No. PLA is very forgiving.

PETG is difficult to get right. Stringy, sticky, wretched stuff. But, if you can get it working, the material has some nice properties.

I believe the symptoms regarding moisture include: bubbling, popping / snapping, and sometimes adhesion problems.

[urbite]

Another issue I’m having is the filament coming off of the side of the spool when feeding. This is primarily for Inland (from MicroCenter) spools, which have the large hub holes and the spools are full.

Can anyone recommend a better spool holder (which I can print) that would also have some kind of guide to keep the filament centered in spool while feeding. There are a plethora of designs on Thingiverse, so any recommendations are appreciated.

On a related note, is there a preferred brand of filament that gives more consistent results than the generic brands such as Inland?