Mini works fine for 30 minutes and then...

I’ve had my mini for about a year now and overall I’ve been happy with it. Lately, however, it has started printing fine for the first 30 minutes and then starts printing into the air but without filament coming out. No birds nest, just stops feeding. I cut off just the right amount of filament for the job just in case the spool was catching, but it still does it. Below are the parameters, I use lulzbot’s profiles for the materials. I just removed the filament from this last failed print and the end of the filament has been scored some and there’s an indent where the grooved feeder just dug into the filament and couldn’t feed. I’ve cleaned it several times, why would it jam up like this?

PLA - MAtterhackers 3mm
205 print
60 bed

Tighten your idler arm springs and see if that helps. About 1mm closer on the washers on either side of the springs. Also consider bumping the temperature up 5 degrees. The springs can cause the bolts to slowly loosen over time. It could also be the thermistor or heater core. Verify the temperature it is reaching with an inexpensive point and shoot thermometer.

If it’s not any of those things, it could also be ovetextrusion, or a damaged nozzle.

Thanks, i was debating getting a new idler arm, but I’ll tighten them down and see. The nozzle is new and I just tested it for obstructions and it looks good. I was debating getting a new hot end or to just upgrade to their new Extruder Toolhead V2.1. I’ll take a look at the overextrusion bit as well. Thanks again.

If it has the small radial cooling fan on the front, is it failing to cool the cold end enough and you may have heat-break lock.

I second this statement. My hot end cooling fan failed after 1.5 ish years and the only symptom was jamming after 30 minutes of print time.

Shameless plug :wink:

Lulzbot Mini 25mm Heatblock fan replacement