What would make a 3D printer suddenly start clogging repeatedly? (CR-10)

What would make a 3D printer suddenly start clogging repeatedly? (CR-10)

My brother and I recently got a CR-10 and went through two full rolls of filament and the original small roll without any clogging or filament issues. Suddenly, it’s clogging every other print. We are using cheap Inland PLA but the first half of the roll worked great. We were running it a few degrees over the high end of the recommend temperature range, as suggested by other CR-10 users who had trouble without doing this.

When it first started we were hearing a “click” sound as the gear feeding the filament would slip/skip. Sure enough, the extruder nozzle was badly clogged. The “Atomic” method for clearing it did not work. We cleared the clog but it happened again in the first layer or two. We cleared it again, thoroughly disassembling the extruder and trying again with a higher temperature but it clogged almost immediately again. The next time we cleared it spotlessly and replaced the original cotton + kapton insulation pieces with equivalents from Amazon. We upped the temps about 5 more degrees and it printed several more items without issue before it inexplicably clogged again. ARGH!

It’s almost like the first half of the spool was good filament and the second half is contaminated/bad somehow. Is that known to happen? Could it be related to humidity? The outdoor temps have changed a lot since our trouble-free days but temperature indoors is controlled. Humidity, on the other hand, has fluctuated. If anything it should be LOWER but if the filament absorbs it over time perhaps that doesn’t matter? Should I build a dry box or is that only for specialty humidity-sensitive filaments? Should I generally remove and store it between prints?

We’ve been out of commission for almost 2 weeks now so any advice is appreciated!

Hello !

Bold to ask for help on a competing printer from velleman’s on this forum :slight_smile:

There may be a faulty head assembly, if the PTFE tube (Cut well straight and not slightly at an angle to ensure a good seal.) has not bonded well to the nozzle if you have a PTFE tube running through the heatbreak.

If you have a fullmetal heatbreak it does not help for a too viscous PLA

Otherwise, you must check the correct cooling of the heatbreak if it heats up too much, there will be obstruction of the filament inside.

Also it is necessary to avoid retraction too long and too slow, because this favors the heating of the heatbreak …

Also check that the spool is running smoothly (no knot) and that nothing is blocking the passage of the filament

It is also necessary to control the tightening of the extruder and whether the motor or the stepper does not heat up.

as a last resort, you can try to lightly oil the filament with canol oil via a kind of foam which would be slightly impregnated with it …

Edit : And a perfect calibrated flow and nozzel/bed distance help to avoid clogging …

Hope this help !