Filament fails to feed after ~45 minutes consistently.  

RE: Filament fails to feed after ~45 minutes consistently.

Try lowering the nozzle temp to 210-215°. Also are you opening the top vent?

Also as a test, print with the door open. 

In the UI goto" Settings -> User Interface -> Footer and set one of the items to [Heat break] this will display the heat break temperature on the screen. If it goes above 50° then expect PLA to soften and cause a clog. 

Also, check if the heatblock assembly is pushed fully into the heatsink. The nozzle should not extend past the fan shroud. 

below the fan shroud. 

RE: Filament fails to feed after ~45 minutes consistently.

No, I didn't open the top vent. Maybe I'm naive, but I thought the Core One Plus would automatically open the vent if necessary based on the material being printed. I'll definitely test with the vent open and open door. I can also crank up the fans. Thanks a bunch for the UI tip. I just set that up now.

The heatblock is correctly inserted as far as I'm aware. I've attached a picture. Tomorrow I'll run the test-prints and see how it goes.  

RE: Filament fails to feed after ~45 minutes consistently.

Posted by: @micrified

No, I didn't open the top vent. Maybe I'm naive, but I thought the Core One Plus would automatically open the vent if necessary based on the material being printed.

That's your problem. With the vent closed the chamber gets too hot, PLA softens and causes a filament clog.

Not sure why the top vent didn't open automatically. That usually happens when the vent is installed backwards. The symptom is M770 O closes the vent instead of opening it. 

RE: Filament fails to feed after ~45 minutes consistently.

I found the Core One Plus upgrade instructions on the vent completely confusing. Had to watch a video to get it right, then still not convinced, I ran the gcode to open and close it. But yes, when everything is right it should automatically open or close at the start of the print. Note that the latest RC firmware is gentler when it whacks the vent open or closed. Before that it was sort of a shock to the system.

RE: Filament fails to feed after ~45 minutes consistently.

Posted by: @conrad-2

I found the Core One Plus upgrade instructions on the vent completely confusing. Had to watch a video to get it right, then still not convinced, I ran the gcode to open and close it. But yes, when everything is right it should automatically open or close at the start of the print. Note that the latest RC firmware is gentler when it whacks the vent open or closed. Before that it was sort of a shock to the system.

I think the OP though bought the C1+. It's possible that whomever assembled the vent at Prusa (or PrintedSolid) did so backwards. 

RE: Filament fails to feed after ~45 minutes consistently.

Yeah I do have the C1+. It's supposed to do this automatically per the marketing / feature documentation, but hasn't been doing so successfully in practice. I tested again today with the same print (this time with the door open as recommended), and saw the display flash with a status about it opening the vent. It made the expected manoeuvre but failed to successfully open the vent, so that might be why I haven't noticed it open so far. I'll have to investigate why it's not making contact successfully. However,  so far the new print succeeded without a jam. So that's good. I'll make another few prints before I call it problem solved though. 

RE: Filament fails to feed after ~45 minutes consistently.

If I were to guess, I would say that this problem is due to heat creep. If the problem consistently happens after a set amount of time, it's often heat creep. So I would also do what hyiger does, but I would focus on lowering the chamber temperature if possible so you don't have to lower nozzle temperature. 

RE:

Posted by: @micrified

Yeah I do have the C1+. It's supposed to do this automatically per the marketing / feature documentation, but hasn't been doing so successfully in practice. I tested again today with the same print (this time with the door open as recommended), and saw the display flash with a status about it opening the vent. It made the expected manoeuvre but failed to successfully open the vent, so that might be why I haven't noticed it open so far. I'll have to investigate why it's not making contact successfully. However,  so far the new print succeeded without a jam. So that's good. I'll make another few prints before I call it problem solved though. 

I wrote some g-code for you to test. Save this to a file and upload it to the printer via PrusaConnect or just copy on to the USB. Next print it. Ignore the warning about incompatible g-code and hit print. Then follow the on screen prompts. It should open the vent, wait 2 seconds then close the vent. 

; Prusa CORE One vent test

G28 ; home / initialize

M0 Manually Close the Vent, then press Resume

M117 Opening Vent
M870 O

G4 P2000 ; wait 2 seconds

M117 Closing Vent
M870 C

M117 Done

RE: Filament fails to feed after ~45 minutes consistently.

Thanks a bunch! I'll give it a try shortly. 

RE: Filament fails to feed after ~45 minutes consistently.

Just jumping on board here to say yesterday I experienced this for the first time too, with my week old self-assembled Core One+ (my first exposure to 3D printing).  I did a few test prints without issue, a long five hour print without issue, then the following day I could not get a single print to finish as it would stop extruding after around 10 minutes, with a loud clicking sound coming from the extruder, and lots of bits of plastic on the extruder gear from where it was grinding the filament.

I tried a few cold pulls, correcting the tension on the idler door (which was a bit high) but nothing would work.  But I was very confused because even with a "blocked" nozzle, each print would start fine and come out perfect for the first 10 or so minutes, so how would that be possible if the nozzle was clogged?

Based on the comments in this thread, I modified the UI settings and added the heatbreak temperature to the footer display, and did some more test prints.  With the door open the print finished perfectly without any issues, and the heatbreak temperature never went above 40 degrees.  With the door closed, just before the heatbreak temperature reached 45 degrees (I estimate around 44.8 degrees) the extrusion stopped and the clicking noises started.  I tried switching the chamber fans from Auto (which had them off) to 40% and this greatly slowed the increase in heatbreak temperature with the door closed, to the point where I managed to get a finished print with the door closed, but the heatbreak temperature did get to 42 degrees.

We're only just coming into autumn here (Brisbane, Australia) so the ambient temperature is around 33 degrees, and the footer shows the chamber temperature blinking blue as "35/20", so these temperatures must be higher than the printer was designed for.

Is there a way to address this problem in the printer's settings?  What I'm thinking of is this, for PLA at least:

• If the heatbreak temperature reaches 38 degrees, start the chamber fans at say 10%
• Increase the chamber fan speed as the heatbreak temperature rises, so that by the time it hits 42 degrees, the chamber fans are at 100% (and also the filtration fan if fitted so it doesn't obstruct the airflow).
• If the heatbreak temperature reaches 44 degrees, pause the print and stop heating the nozzle, move the plate down away from the print head, and let it sit there until the heatbreak temperature drops below 40 degrees, then resume printing.

This would slow down printing if it had to keep pausing waiting for the heatbreak to cool off, but in my opinion that's much more preferable than a failed print.  If it also displayed a message on the screen like "Heat creep detected, cooling off" then it would also give people something to search for rather than thinking it's a clogged nozzle as I did.