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I am at my wits end with this problem. I start a print and the skirt goes down fine, then the outline of the parts go down fine (usually) and then when it goes to fill in the first layer, it will always get stuck to the hotend at some point and rip apart the layer.

Any ideas on how to solve this?

  • Printing PLA at 210°C;
  • First layer temp is 225°C;
  • Bed temp at 60°C;
  • 1.75 mm filament, and;
  • 0.4 mm nozzle.

Maker Select V2.1, using Cura to slice.

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Step Zero: is always to check/adjust the bed level - if the height over the bed varies while putting down the first layer, it's hard to ever get first layer settings that work.

Step One: is to adjust your first layer settings - height, temperature, extrusion width until you find a set that work for your setup (knowing that they may change somewhat when you change filament.) Some folks find more success with thin first layers, others with a thicker first layer to pump more plastic, still others use the same layer height but increase the width to pump more plastic, and others combine these approaches. Increasing the temperature is common, though in my case I found that the "usual" +5°C was not enough for the present setup.

You can change one setting at a time and have an idea of what works better or worse in each case, or you can change lots of settings and hope you get lucky. I prefer the tedious approach, it's less maddening.

Are you using any surface treatment on the bed? A bit of gluestick or hairspray may help you stick.

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  • $\begingroup$ Thank you. Is the proper z height a pice of normal printer paper with slight drag? Can you help me understand extrusion width? I think in Cura it's defaulted to my nozzle width of .4mm. For bed adhesion, I am using blue tape. I'm just having a real hard grasping why the skirt and perimeter goes down fine but the solid bottom layer is getting torn up. $\endgroup$ Jun 15 '17 at 18:15
  • $\begingroup$ I assume it must be there somewhere in cura - in slic3r there are defaults, but you can tweak/adjust them and I certainly have. Extrusion width is just what it sounds like - the slicer feeds more plastic at a certain height so that the nozzle flat end forces it to squish out wider than the hole in the nozzle. Another thing might b $\endgroup$
    – Ecnerwal
    Jun 15 '17 at 22:14
  • $\begingroup$ be speed of travel when printing. I don't know what cura defaults to, but Slic3r certainly slows down the outer perimeter as a default, so slowing down might help. I feel like you might have jumped the gun on accepting the answer if you're not yet printing successfully.... $\endgroup$
    – Ecnerwal
    Jun 15 '17 at 22:33
  • $\begingroup$ I suppose your right that I jumped the gun a bit.... I measured my paper that I was setting the nozzle height with and its a bit less than .1mm. I'm wondering what a normal height to set the nozzle is. I also measured my filament and from the sections I measured its mostly 1.72mm vs 1.75. Could that be an issue? So I'm going to level the bed, set the first layer height to .2mm and .4mm extrusion width (that's my nozzle width) and the temp to 205. I will tweak one thing at a time and write it down . does that sound like the right way to go? $\endgroup$ Jun 17 '17 at 14:47
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The solution was moving to a glass bed with AquaNet for adhesion, and discovered a partial clog that was causing under extrusion.

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Check if you have fan turned on for 1st layers. Cooling fan must be turned off for initial layers. That's a mistake I've made.

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I would ramp back on both temperatures. My personal "sweet point" is closer to 50° bed and 195° hotend for PLA. Typically the problem of extruded material getting stuck to the hotend occurs because the extruded material is not adhering well to the bed. In your case it may simply be, as Ecnerwal suggests, nonoptimal Z-height adjustment. Or it may be that the PLA isn't cooling quickly enough to adhere well, and thus is being "dragged" along with the extruded feed.

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  • $\begingroup$ This is interesting. The fan is off at the first layer. Maybe I need to turn it on. I will try lower temps tonight. Thanks. $\endgroup$ Jun 15 '17 at 18:16
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Try lowering your first layer temp to 205°C, and apply a gluestick to the bed before you print anything. By lowering the temp, this allows th plastic to cool faster, and doesn't risk the plastic sticking to the nozzle as much. Applying the glue stick will help the print to stick to the buildplate better, lowering the risk of it getting stuck to the nozzle. You might also want to try using a raft, as this will provide more surface area for the print to stick to the bed with, and lower the chances of it attaching to the nozzle.

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  • $\begingroup$ Please expand upon your answer, as it stands your answer is very terse, and may be deleted. For example, please explain why would this two things help? $\endgroup$
    – Greenonline
    Jun 17 '17 at 18:51

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