Stringing problems: should I take the extruder apart?
Mk3s+
I think I need to, but since I'm a beginner (second hand printer), I wouldn't mind some confirmation.
I have stringing issues. Last runs, on Ender PLA, 215⁹C for first layer, 190˚C after, left to right is 2mm retractation, 1mm retractation, 0.5mm retractation (if you spot a difference, let me know…).
Oh, printer is in the basement's office. I have a dehumifier running, so humidity is typically 51--56%, and I used a filament dryer for hours (Sunlu S1 set at 50˚C), but I always wonder how fast it would absorbs back moisture.
Based on reading around, it could be also be that I need to adjust the extrusion multiplier setting, but I assume the Ender PLA cannot be that exotic compared to generic PLA settings, and adjusting that setting to compensate a faulty extruder is a bad idea (I can only imagine: system running in abnormal operating point, with potentially more parts wearing faster, continuous drifts, etc.).
So, if I suspect the extruder to have some issue, what would I be looking for?
That *looks* like wet filament ... check your dryer is working correctly and venting the moist air - if not the moisture will be re-absorbed.
Is this a relatively new nozzle or one that has been in use for some time?
Cheerio.
RE: Stringing problems: should I take the extruder apart?
Thanks for the answer!
The nozzle is ~550h of printing. I don't have a hygrometer, will get one. Since I've read here and there that 50% RH seems to be the trigger beyond which issues appear, I had assume I have a low gap to get moisture down to an acceptable level. Was that a wrong assumption?
550h - about a couple of months at 40% duty - ordinarily it should be OK but if this is second hand and you don't know what's been put through it perhaps a replacement would be sensible.
I generally aim for 10% RH 'though I don't always get there, in general below 20% is OK. Don't forget that all the time you are printing the spool is absorbing moisture from the air.
After a while you will find you can go by the feel of the filament without recourse to the hygrometer. PLA should spring a little, not feel too stiff and certainly not snap under light pressure.
Cheerio,