Your extruder idler screw *might* need a tweak...
Switch the filament with the reel that is printing well on the other printer, print with both; does the issue follow the filament?
Cheeriio,
RE: Stringing Issue Prusa MK3s (PLA)
I tried adjusting the idler screw and swapping reels. The same filament works fine on the other printer.
Any other suggestions?
Your extruder idler screw *might* need a tweak...
Switch the filament with the reel that is printing well on the other printer, print with both; does the issue follow the filament?
Cheeriio,
Stringing and oozing is almost alwayseither damp filament (90%) or too high temperature(9%), the next thing to check is a worn or damaged nozzle ... but dry it again first.
Cheerio,
RE: Stringing Issue Prusa MK3s (PLA)
I know that is normally the issue, my machine pulls directly from a filament dryer and the machine has been printing fine with this filament for six months until the rebuild. Unless the thermistor is way off.
RE: Stringing Issue Prusa MK3s (PLA)
Reading your post, it is not clear what parts you have replaced. If you replaced the fan, you have to check that the flow is equivalent to the original. If not that the case, you have to check if there is any other damage to the gears that push the filament, or wrong length / positioning of the PTFE tube.
RE:
A badly worn nozzle can also cause stringing.. I don’t see this as a mentioned cause.. although one poster mentioned he changed the nozzle and did not fix, but changed the hot end and it fixed the issue.
In my case a badly worn nozzle caused stringing in most of my filaments. I started blaming the manufacturer, but when I extruded some plastic and measured, it was 0.55 for a 0.4 nozzle. I replaced the nozzle and compared under a microscope to a good nozzle and it was obviously much larger and worn. (In only 8 months, without printing abrasive filament.. don’t think galaxy PLA is abrasive). Anyway that removed stringing for me. Now I’ve also had stringing due to humidity, but a worn nozzle seems to extrude more filament than the software expects.. causing stringing. Simply extrude some plastic and measure it with digital caliper.
RE: Stringing Issue Prusa MK3s (PLA)
Reading your post, it is not clear what parts you have replaced. If you replaced the fan, you have to check that the flow is equivalent to the original. If not that the case, you have to check if there is any other damage to the gears that push the filament, or wrong length / positioning of the PTFE tube.
I did not replace the fan. I replaced the PTFE tube with the little connector. But good suggestion I will check the gears for damage.
A badly worn nozzle can also cause stringing.. I don’t see this as a mentioned cause.. although one poster mentioned he changed the nozzle and did not fix, but changed the hot end and it fixed the issue.
In my case a badly worn nozzle caused stringing in most of my filaments. I started blaming the manufacturer, but when I extruded some plastic and measured, it was 0.55 for a 0.4 nozzle. I replaced the nozzle and compared under a microscope to a good nozzle and it was obviously much larger and worn. (In only 8 months, without printing abrasive filament.. don’t think galaxy PLA is abrasive). Anyway that removed stringing for me. Now I’ve also had stringing due to humidity, but a worn nozzle seems to extrude more filament than the software expects.. causing stringing. Simply extrude some plastic and measure it with digital caliper.
Thank you for the suggestion but that isn't it, I subsequently replaced the nozzle and it did not solve the problem.
RE: Stringing Issue Prusa MK3s (PLA)
It is true that a worn nozzle can create stringing, but not because it is extruding more filament. The extruded filament is regulated by the gears of extruder, that are taking command from the g-code file.
The problem is created when the specified amount of plastic that is fed through the worn nozzle is spread to a bigger width than that the software "knows". So the "line" shape is not flat with rounded edges, but is "moving" to an elliptical shape. So adhesion to the the previous layer is less "rigid" . When the head is going to stop feeding filament in order to "jump" to another position, the extruder retracts the filament. We have to consider that the bigger diameter of the worn nozzle is creating bigger adhesion between the printed "line" and the melted plastic inside hot end. So when the filament is retracted, the force trying to "suck" the edge of the printed line is bigger. And as we have less adhesion of the line to the previous layer, the "line" is not being cut but is retracted creating a string.