After a print has finished, filament will ooze out of the nozzle about 1" until the nozzle cools. When the next print starts it flings the 1" of filament often on the print bed before purging the nozzle. This happens more often then not. This seems to be preventable.
How are you drying your filament? Often oozing like this is caused by moisture in the filament. The moisture expands in the nozzle and the only path for it to exit is via the nozzle and by pushing filament out of it. Also are you printing from an AMS or from the external filament holder? The AMS retracts the filament at the end of the print which reduces pressure. The external spool leave the filament in place.
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I originally dried this particular filament in the AMS2 pro but its been 3 weeks and while that particular roll of filament has been in the AMS all this time I’ve added other reel of filament since so it might be contaminated. I’ll dry again and retry. Thanks for the response
The AMS doesn’t keep filament dry, it just slows down how long it takes before it’s wet again. You need to regularly run the heater to redry even if you don’t open the AMS to put a new roll in.
Filament doesn’t drip out of a nozzle on its own, the melted plastic is too viscous, the nozzle opening is too small. If you see filament being driven out of the nozzle when the extruder is hot but the extruder motor isn’t running, something is driving it out and that something is always moisture in the filament.
So when you see this happening, no matter how dry you may think your filament is, it is not dry. 
Dry filament will not ooze (or if it does, it will be a tiny, tiny amount, because there’s no practical way to get filament moisture content to zero so it’s not technically completely dry).
Is this an H series? I have noticed they are drippier than the P or X, it’s fixiable in the gcode; i’ve seen the fix it on this forum somewhere. Bambu really should mod the firmware or slicer to fix it tho,
My H2C is no more or less “drippier” than my X1C. And neither is “drippy” (or oozy) at all, provided I make sure my filament is dry.
Gravity can and does gently evacuate a hot and standing nozzle that has filament in it, but nine times out of ten if you are noticing it, and it is egrigious, it’s coming from moisture in the filament, boiling, forcing large amounts of itself out the only hole it can go.
I notice it’s quite significant with PETG. It’s something to do with being unable to cool the nozzle quickly enough, and then not wiping properly when it starts up.
It’s worse when uisng dual nozzle (perhaps more residual heat meaning the nozzles cool slower)
Everything is well dried.
This has been a valuable lesson for me. I dried some Sunlu PLA Rainbow Transparent using the AMS before, but the first print had this. Now I know what to look out for and make sure it is dried fully. I dried it statically for 12 hours using the PLA setting on the AMS 2 PRO so perhaps the the filament that is inserted at the beginning was still wet as the drying only did the spool up to the tube…
Snot running down its nose… is because it is wet. 
Thanks everyone for your input, its greatly appreciated. I just wanted to add that I agree it makes sense that its probably due to moisture but the prints come out flawless. It wouldn’t hurt if bambu changed the sequence so that it did a nozzle wipe before trying to clear the poop chute first when starting a new print. This is on a P2S and using bambu PETG-HF. I dried my filament out overnight and will try again to see.
I just got home, the filament has been drying for 18 hours in the AMS2 Pro and finished drying this morning, the AMS2 is showing 0% and got home after work about 15 minutes ago and I started a small 15 min print. It printed flawless, I am using PETG-HF and after it finished printing there is still a 1" long strand of filament sticking out the nozzle.
Can you attach the text in your end gcode or even better yet, attach the .gcode.3mf file you just printed.
Tab_Oper_v7_-_PETG_0.20mm_High_Quality.3mf (843.6 KB)
Here you are
No I was hoping for the .gcode.3mf file. The file you send to the printer as this will have the gcode your printer is actually running.
Click arrow next to print plate, and change to “Export plate sliced file”
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sry still new with the g-code stuff
Tab_Oper_v7_-_PETG_0.20mm_High_Quality.gcode.3mf (997.9 KB)
notice that as well. My X1C doesn’t drip or trap much purge in its tower, but my H2D’s purge tower is definitely full of that, and my H2D also will on occasion have that happen. I’m using ABS, and I also make sure the AMS have had a round of drying every so often, so I don’t think it is moisture. My fix is just to have a prime tower, as that seems to catch everything, and it also makes nicer videos as well.
Ok again this morning i printed out another print and and again the filament is dried twice now and with the new firmware I am now drying while printing AND the filament is not oozing out its shooting the filament instantaneously and purposely out the nozzle as soon after the print head parks after a print. I uploaded it if someone doesn’t believe me
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Hi. I’m just about to get into printing and I was wondering why the filament is wet in the first place.
Also will a toaster oven work at drying it out and what temperature and time would be needed?
The filament absorbs moisture from the air. Different types absorb different amounts. I live in the subtropics so it is more of a problem for me that probably most. I needed a machine to to do it as is could measure the moisture levels as it went and I didn’t need to wait around and watch it.
I don’t know about a toaster over… hopefully someone else can give advice on that.
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