I bought the printer for it’s dual head multi material printing capabilities, specifically to use different materials that won’t bond together within the same print.
Lately, when I have been trying to print with PCTG (left nozzle) and PLA (right nozzle), about one hour into any print I get a extrusion error with the PLA nozzle. Sometimes it is extrusion motor overload, some times it’s a failure to extrude, other time’s it’s that the AMS failed to feed the filament. The wiki points me towards a clogged nozzle as the possible issue, but I’ve tripped checked using multiple nozzles and it’s not a nozzle clog issue.
Often times this error has coincided with a very heavily warped piece of filament within the extruder that I have to remove by manually taking the entire extruder appart (huge pain), but this doesn’t always happen. So my first instinct was that the hot end wasn’t getting hot enough for the volumetric flow that the extruder was attempting to push out. So I ran flow dynamic and flow rate calibration tests, which all worked fine no issues, and tried printing at the new settings.
Same issue. My next instinct was to increase the print temp manually, and re-calibrate flow rates based off the higher temps. So I went from 205 > 210 > 215 > 220 > 225 > 230. Same issue at each temp, even though flow calibrations work without a hitch.
Here’s the fun kicker. I can print a PLA only model using the exact same calibrated filament profiles at each of those temps without any issue. This only happens when I try to print using two different material types (at two different temps).
Is it possible that there is some heat creep going on between the two nozzles that is throwing off the temps in the PLA nozzle? My only other idea would be that there’s some type of an issue with the gcode when switching heads, even though the same filament is in each nozzle for the entire print.
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actually, after posting this I was looking at more settings and I noticed that the chamber temp was running at 40C during the prints even though it was suppose to be set to 20.
So this is most likely the cause, due to the softening of the PLA once chamber temp got high enough. Will try a test print and see what happens!!
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Yes, sounds like the issue is definitely there, let us know how it goes!
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If you use H2D and latest beta you should be aware that their solution to the “hairy” wipe tower lowers temperature while printing on the tower.
If you then use TPU it will create high back preasuure and just wind up the TPU in your extruder.
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Great!! I’m in the beta, but it hasn’t updated yet. I don’t print tpu often, but this is good to know. Wonder how long until that is fixed.
The print was running amazing while forcing the exhaust fan to 50% to keep temps under 31C. Then I woke up to a spaghetti monster. Sock on the print bed, extruder cover popped off and under the bed, model not adhered to the plate, and hot end covered in filament (not the pla hot end 
).
I don’t know what the series of events was, but I’m pretty sure it’s unrelated to the extruder overload issue I was having before involving the pla support. So keeping the temps in the chamber below soften point did solve that issue.
Strange though, be as both filament profiles I had loaded for the pctg and pla has chamber temp at 0. If I print pla alone, I don’t have to monitor the chamber temp, but even with the chamber temp same on pctg profile, I need to. The increased temp of the pctg hot end must raise the temp in the chamber just enough in its own.
I am having the EXACT same issue as you, but I am using the P2S with a single nozzle. Same issue though; I can print a single print in PETG fine, and I can print a single print in PLA fine.
When i am trying to print an item thats in PETG and use PLA as supports, it will error with the exact same error you said; Either extrusion motor overload usually. And when i tear it down, the extruder has a tiny chunk in there that jams it up or a nice long line of it that wont backup or extrude…even though the PLA is clearly flowing out of the nozzle slowly…
I’ve done the same thing you did, higher temps, used flow-rate calibration profiles…nothing has worked for this…but as soon as i cleared it, i printed a PLA print only while using that PLA profile, and again with PETG, then back to PLA…but somehow, swapping between the two, when trying to use supports for a TINY portion, simply isn’t allowed.
SOMETHING has to be the issue here, and i hope you maybe found a solution that you can enlighten me with, even though you have a dual nozzle machine and mine is a single.
It turned out that the chamber temps were getting too high, which was softening the PLA to the point where it became flaccid and would get jammed up inside of the extruder. I modified the PCTG and PLA filament profiles to lower the print temps so that it didn’t happen, but quality suffers
i dont even see where to adjust the chamber temps in bambu studio…or do you have to do it manually with gcode or something?
Im willing to give it a try just because most of the things id be wanting to use PLA supports on are very few and far apart…like, i wouldnt have an issue continuing to use PETG for supports, so long as i could remove the supports easily without any scarring…and i know it can be done, cause ive seen people remove PETG supports with no issues and no scarring…but so far, i cant seem to get it right, with being able to remove them and not have rash scarring.
Chamber Temperature is managed under the filament settings
I believe im in the right area…i clicked the “…” next to my filaments and i see filament settings open up. However i still dont see anything in this menu for chamber temperature, and this is where i was looking earlier.
I am not at the PC but it’s on the first tab. Just scroll down.
Make sure you select the correct nozzle type on top.
Unless your printer has no chamber temperature control.
I missed you were using a P2S. That has no chamber heating capability.
So temperature management is based on how far you open the door.
thats…uh…perfect…thanks bambu…
