CR 10s Crazy Print Errors & I am Totally Clueless


Hello- I have a CR-10s and have been getting some weird print failures on my last 5 prints and have run out of options and need some help if you guys don’t mind.
I am printing sidebars for my Daft Punk helmet at 0.2mm, 100 percent infil with PLA at 205-210 with a bed of 60 degrees and sliced with Cura. The object is pretty large and I have done many prototypes in the past but I have been getting weird glitches with the last 5 prints (see pic) where I have a perfect print for a while, then the extruder starts to make like a crumbly dust on top of the print then the Z axis lifts off the print and starts laying spaghetti. Sometimes it is a few millimeters (see pic), and one time it was over an inch (see video link below). I have no clue what is happening. I even tried thinking it was bad G-code so I reverted my Cura to the older version (3.3). Could any of the below be the culprit?

  1. Stepper motor/stepper driver overheating?
  • Should I put a heatsink/fan on the X and Y, or on the stepper driver boards?
  1. Bad STL/OBJ export from my 3d modeler?
  2. Bad slicer settings/G-code?
  3. Electrical surges?
  4. Control box overheating?

Oh and BTW I have trammed the gantry and confirmed level after so I am pretty sure it’s not a bed or Z axis issue. Any help is appreciated and thanks in advance for your help!

Video link is here:



Hi Random,

I’m not sure what the problem is, but I think I can help reduce the suspects:

  1. Steppers don’t generally overheat, their drivers do. (Ok, they can, but then you have bigger problems.) Yes, you should have heatsinks on the drivers, if just for very cheap insurance. Anyway, when drivers overheat they will often either shut down or skip steps. Skipping steps is more common from too low a current, though.

TL&DR: skipping motors would not create big gaps, but rather offset prints. Except for your extruder. No filament = big gaps.

2&3) Bad settings, export, etc. Maybe. Download MeshLab (free). It can help you locate holes, non-manifold geometry, etc. Is the print consistently failing in the same spot?

4&5) Unlikely. This is a digital machine. Mess with the power and you’re finished (not counting fancy firmware that tries to recover).

Bonus: check your hardware. I know you said that you trammed the gantry. Is the printhead or xy carriage bumping on something? Look carefully. Loose coupler? Bad connections to the board? Is the nozzle jamming? Old or cheap filament can do weird things.

As a side note, I am curious why you are printing at 100% infill. 20-30% is lighter, cheaper, AND stronger than solid. If you are drilling or cutting into the pieces, you can design them with those needs in mind. 3 or more shells and you probably won’t see the infill pattern either.




Thanks Stefan. I downloaded Meshlab and checked the stepper drivers. They do have a heatsink. I will check out all of your recommendations. The more feedback I get, the more I think that it’s a hotend problem (i.e. a clog). I am thinking about Octoprint so I can see if there’s a drop in temp or other anomaly that is causing a clog. What do you think?

PS- I printed at 100 percent infil mainly because I thought since it has LEDs, diffusion material and colored gels inside the print, it would not show a weird light pattern through the side if it wasn’t solid. Now that I have one side complete that was printed at 100%, I need the other side to match so I feel like I am committed.



This is a common CR-10 issue. It’s often caused by the PTFE tube slowly slipping out of the hotend. This causes plastic to build up inside the extruder, which slowly causes the hotend to extrude worse and worse.

Short-term fix is to remove the nozzle and PTFE tube, heat up the hotend, and push all of the gunk out of the hotend. Clean the nozzle. Screw the nozzle back in when hotend is at print temp. Cut off the tip of the tube if it looks burnt, and push it back in.

Long-term fix is to replace the hotend with a higher-quality option like a genuine E3D (preferably a volcano for the CR-10).