Sudden bad print quality
Hello all,
I have a mk2.5 I upgraded from 2S and it just started failing. It has been working flawlessly for about two months after the upgrade, and then it just suddenly started having what appears to be extrusion problems (pic attached).
I have gone through Prusa’s common problems and haven’t found anything wrong. I have also pulled the extruded apart, opened the hot end to check the ptfe tube, done several cold pulls, all with no improvement. I’ve used three different brand new spoils of filament so I know it’s not that.
I am beyond frustrated at this point and am out ideas, but I really feel like it must be the extruder somehow, but I would really appreate any help possible.
Re: Sudden bad print quality
Maybe it's not the extruder; maybe it's a problem with one (or more) of your axes of motion. From your pictures, it seems to be related mostly to Y and Z, but of course X is not out of the realm of possibility. If you send commands to move in the various axes, are the movements smooth? Are your Y and X belts properly tensioned? Is it possible that you need to lubricate your smooth rods and the threaded rods on the Z axis?
Another possibility is that some bolts have become loose (or something broke or melted) in your extruder body, and your extruder nozzle is not firmly positioned relative to the X axis rods. If you can wiggle it by hand (when it's cool, of course), then you know you have a problem.
Just some ideas for you to try...
Re: Sudden bad print quality
Thanks, yes I have checked all of those things and everything seems ok. Also the extrusion on the first layer and the initial print line is no longer even - parts over-extruded and parts under-extruded.
I haven’t specifically sent commands to move the axes but during the initial setup routine everything appears to move ok. I’ve run an extruder calibration process from Matt’s Hub, and that also seems ok.
One thing I have to try that I just read about is is feeding a rod of some sort down through the filament path to make sure there are no snags.
Re: Sudden bad print quality
did you try a new nozzle?
I have a Prusa,therefore I research.
Re: Sudden bad print quality
did you try a new nozzle?
Not yet, it that’s next. It seems odd to me that the nozzle would go bad from one print to the next - I would thing it would gradually get worse, but I suppose it depends on the type of problem. I have a ruby nozzle which has been pretty tough so far. But I will definitively try another nozzle and see if anything changes.
Re: Sudden bad print quality
i wouldn't think a ruby nozzle would ware out. but with normal nozzles that's what I try next on the list
I have a Prusa,therefore I research.
Re: Sudden bad print quality
i wouldn't think a ruby nozzle would ware out. but with normal nozzles that's what I try next on the list
Yeah that's my thought too.
So I'll pulled my ruby nozzle and put in a brand new brass one - it looks that may have been the issue (facepalm). I should have checked that first... I haven't had to do much troubleshooting in my two years of owning it 😉
I'm printing some tests now to see if it holds up. I also need to clean the outside of the ruby nozzle - it's pretty gunky. Perhaps there was just too much built up plastic on the outside of the nozzle... I'll find out shortly...
Re: Sudden bad print quality
ruby nozzle 2 years old? hopefully it didn't crack, but if you got 2 years out of it. I use about a nozzle a month (ish)
don't forget a new Z height. mine just changed by .023 from a new nozzle.
I have a Prusa,therefore I research.
Re: Sudden bad print quality
Yeah that's my thought too.
So I'll pulled my ruby nozzle and put in a brand new brass one - it looks that may have been the issue (facepalm). I should have checked that first... I haven't had to do much troubleshooting in my two years of owning it 😉
I'm printing some tests now to see if it holds up. I also need to clean the outside of the ruby nozzle - it's pretty gunky. Perhaps there was just too much built up plastic on the outside of the nozzle... I'll find out shortly...
Well, still having problems on the new nozzle... see attached
The accuracy looks pretty good, nice corners and what not, but something is still off.
Re: Sudden bad print quality
Another thing I noticed is that the nozzle temp seems to rise and fall about 1.5-2.0 degrees in a repeating pattern - is that amount of change anything to worry about?
Re: Sudden bad print quality
Another thing I noticed is that the nozzle temp seems to rise and fall about 1.5-2.0 degrees in a repeating pattern - is that amount of change anything to worry about?
Well, it looks like this may have been part of the problem, which actually just presented itself. I was printing some more tests and and found a set screw in the middle of the bed after walking away for a bit. It turns out the thermostat set screw in the hot end just fell out.
So after putting the screw back in, I printed a new test and it was much improved. I'm printing a benchy now and then some larger prints to see if that resolved issue fully.
I've seen several other posts about that set screw falling out - so perhaps this is something to be addressed with E3D and Prusa, but one to add the knowledgebase I think.