Type of filament used - PC (Sold in NZ by 3DEA), filament was dried fully ~2 days ago, and put in desiccating oven for 1 hour before printing.
I have been trying to print a heater outlet duct in Polycarbonate (PC), but it is failing at the exact same place 3 times now. The material is becoming blocked in the nozzle. The blockage at the nozzle tip appears to be minimal, but when I removed the filament carefully from the nozzle and extruder is appears there has been heat soak and the filament has softened. Then with the extruder pushing filament to the nozzle, the filament has compressed and deformed. Once the heat has travelled up the filament far enough, the material inside the extruder housing has again compressed and deformed. This causes the filament to jam in the extruder. I have had similar issues on my other X1E, X1C and P1S machines in the past. But this one seems different.
Why does it occur at the exact same time 3 times? This is the 3mf file. Heater duct.3mf (122.1 KB)
Failing at layer 13 every time, I can identify it by the “top surface” pattern. I also think it is weird that it is printing a full top surface layer at the ending of the flange, before starting to print the duct walls.
I did not respond initially because I have very, very little experience with PC. Also, while having dealt with the occasional extruder clog, they are much rarer for me than nozzle clogs.
When I do have extruder clogs however, it is usually when printing large, thin surfaces slowly. Ironing is worst for this.
So it may be a question of needing to increase this layers flow without causing other problems.
Are you able to print this surface faster and/or thicker to increase flow?
Also, do you have a slicer preview of the flow?
And, of course, is it carbon filled filament or just black PC?
Finally, but this is just a guess, I am usually getting mixed results with concentric surfaces, but this print looks like it could work with such a pattern which in turn would probably allow you to speed up that layer a little as it has far fewer acceleration jerks.
Hi Eno, thanks for the response. Speeding up the print in that area definitely wouldn’t be an issue. And you’re correct concentric would likely be a better pattern for this flange and duct. The file was sliced by a student and I didn’t modify.
The filament is PC only, not CF.
To me the issue appears to be heat soak into the filament, so I am printing a vented front cover and a Biqu Jetpack clone. I’ll print them on my Form 2 in HT resin.
My experiences with mods on the X1 is that I am usually better off without them But I can certainly see that the opening up of the front cover should improve cold end cooling Maybe, that is already enough.
Another very easy thing that could be done, and which may help education if you can ask the student to do this , would be to insert a pause before layer 13, prop up the top cover a little bit to lower the chamber temp by a few degrees. Of course there’s an increased risk of warping, but hopefully, a few degrees is all we need.
I discovered early after release of the X1C the AMS motors are too weak and cannot combat the excess thermal expansion of the filament in the printer+the run from the AMS, and would routinely jam like this.
If I would remove the PC roll from the AMS and manually load in the back of the printer and put the spool on top of the printer (in an air tight tent btw) it would stop jamming.
Not sure if you’re using an AMS but if you are, I’ll bet money that’s what’s going on. If this is the only spool loaded, via the back, perhaps it’s just a lower melting point affected by the ambient heat buildup while printing? What happens if you put the chamber fan at 80% to vent some of the excess heat?
Hi,
i take a look on your file and at the lines of the 13 layer. I don´t like the smal gray gap-layer. if you change the settings shown in the picture it prints more smooth and don´t need to print this smal lines. i try always to construct on a way to avoid this. In my opinion the reason for your fail is to much speed and to low temp. because of fan. So set all speed to 50 and switch all fan off.
no bridge no fan…
good luck
Thanks Windy! The engineer in me wants to only change 1 thing at a time to pinpoint the root cause, but I also just want it to work…
I’m going to make a smaller test print with the patterns changed to concentric to see how that prints first. Then I will change your wall width settings (lucky I know some German and the student this print is for is actually from Munich ). Are these standard settings you use, or did you do some calculations based on the dimensions of this particular part?
If I can get it to work well without mods to the print head, then great. And I’ll probably just put those modified parts on afterwards.
…hi my friend,
am back from the aferwork beer. …bavarian style
i tryed many solutions in settings for your printing part before i post it.
the posted settings are good…only for your part.
normalliy i print with default settings.
so…go slowly and stop the fan.
good luck
But I can certainly see that the opening up of the front cover should improve cold end cooling 
Maybe, that is already enough.
, would be to insert a pause before layer 13, prop up the top cover a little bit to lower the chamber temp by a few degrees. Of course there’s an increased risk of warping, but hopefully, a few degrees is all we need.
& 
). Are these standard settings you use, or did you do some calculations based on the dimensions of this particular part?