Failing or Missing Layers; Stepper Problem or Slic3r?  

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

Were these pre-sliced Benchy's or ones you sliced?

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

I think I've seen this problem myself, and have yet to diagnose it. I'll post my pics when I get home tonight, I'd love some feedback on this.

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

Were these pre-sliced Benchy's or ones you sliced?

I used slic3r to prep them, then sent the gcode to octoprint and printed from there.

Here's a print isolating each stepper showing steppers 1-4 from left to right. I got the same layer failure on steppers 1-3 but 4 (green) seems fine. Maybe it's Octoprint?

I can post the timelapse sometime Tuesday if that helps.

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

Most likely cause: blockage due to stringing.

See this thread: http://shop.prusa3d.com/forum/original-prusa-i3-mk2-multimaterial-f26/blockage-troubleshooting--t4643.html

Peter

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

Most likely cause: blockage due to stringing.

See this thread: http://shop.prusa3d.com/forum/original-prusa-i3-mk2-multimaterial-f26/blockage-troubleshooting--t4643.html

Peter

Hi Peter,

Thanks, but I'm not clear on what stringing is. Could you point me in the right direction? Also do you know why only does it for a few layers then recover?

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

Thanks, but I'm not clear on what stringing is. Could you point me in the right direction? Also do you know why only does it for a few layers then recover?

Stringing of the filament tip during unload. It can block another filament from loading properly and then when that filament is unloaded, it unloads too far, so misses the next layer or two.

It can also remove the string left behind by the bad unload.

Drop your temps by 5 degrees or so. Print slower if necessary.

Peter

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

Octoprint could not have an effect like this.

I agree. Blockage.

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

Hi guys,

After taking your advice, I dropped temps to 190 and slowed the print down. I've dropped temps twice and the filament continues to jam in the hotend and is unable to retract very similar to http://shop.prusa3d.com/forum/original-prusa-i3-mk2-multimaterial-f26/jamming-in-the-steel-tubes-t4914.html

I'm seeing repeated print failures halfway or even 80% through the print, even though the first half is perfectly fine. Sometimes its one extruder, then another. It's even worse now with total jamming occurring on the bearings. My recent attempt at the 3dBenchy was better but far from perfect. I have one of the bowdens that is only tapered internally on one end, if that helps.

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

Have you read through this thread: http://shop.prusa3d.com/forum/original-prusa-i3-mk2-multimaterial-f26/blockage-troubleshooting--t4643.html

Peter

Re: Failing or Missing Layers; Stepper Problem or Slic3r?

Have you read through this thread: http://shop.prusa3d.com/forum/original-prusa-i3-mk2-multimaterial-f26/blockage-troubleshooting--t4643.html

Peter

Thanks Peter,

I think it ended up being too much tension from the filament roll not unrolling properly and snagging because of the back feed causing the roll to loosen then the line to cross weirdly on the roll, so when the material switched back, the roll wouldn't feed as well and cause a jam. I didn't notice initially because the roll would recover after the stepper pulled the knot out. The one single material failure looks like it was also because of a filament roll feed failure.