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I recently took my first shot at printing with specialty filament -- Entwined by 3-D Fuel -- on a Lulzbot TAZ having an 0.5mm nozzle. (Note that this is the original Entwined, not the mid-2018 "v2" with smaller fibers; Just purchased from MicroCenter this weekend, and saw a 2017 production date when reading the label).

While the filament in question can be reliably and consistently extruded at full speed (as with the "Continuous Load" button), I've repeatedly had it stop extruding partway through my prints. This is much worse with lower layer heights. Even when this has happened and several MM have been "printed" with no content, pausing the print, going to the load/unload menu, and telling it to extrude filament at full speed indicates that it's not by any means fully clogged, but only failing to extrude at the configured speed.

Where should I start in tuning to try to get a reliable print with this specialty material?

I'm using Cura LE 3.6.9 for slicing. The center item of the three below was printed at 210C, with the most successful at 0.25mm layer height (Cura's default of 0.1mm had far worse results -- not included in the below photo -- with the base layer almost not being there at all; 0.175 did somewhat better).

I'm using the bed heated to 45C, in line with the manufacturer's guidance (that a heated bed is optional, but should be set to 45-60C).

Samples of prints failed after first few layers

Charles Duffy
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  • Welcome to 3dPrinting.SE! What extruder/bed temps are you running? When you say it "repeatedly" stops printing, is it in the same place or anywhere close to it? What layer height are you using? Can you give us the rest of your settings as well as possibly a pic of what it looks like when it stops printing? – Pᴀᴜʟsᴛᴇʀ2 May 19 '19 at 21:44
  • @Pᴀᴜʟsᴛᴇʀ2, thank you for the welcome! I didn't retain the GCode for every print attempt, so I haven't been able to exactly replicate all my settings; that said, I've added some photos, and what settings I could find. – Charles Duffy May 19 '19 at 23:28
  • "Entwined hemp filament can be printed on any machine capable of printing with PLA using standard PLA settings." - this suggests to me it is best to he treated as a fiber filled PLA, which means usually large (0.4mm+) nozzle and thick layers to prevent fibers clogging the nozzle. – Trish May 19 '19 at 23:32
  • @Trish, thank you! I'm already at a 0.5mm nozzle, so we're good on that count. Needing to use thick enough layers is pretty clearly part of my problem; advice from someone who's had success with fiber-filled PLAs (and thank you for pointing out the wording there; I'll edit the title to be more specific) on what constitutes good layer size might well be the core of what I need. – Charles Duffy May 19 '19 at 23:39
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    I've found that fiber-filed filament is much more reliable through a .8mm nozzle. – Davo May 20 '19 at 00:14
  • Much later, I also found out that when I was encountering this issue my machine had a faulty thermistor, and thus was not consistently holding the correct temperature. That likely had more than a little to do with the problem. – Charles Duffy Sep 30 '19 at 22:07

1 Answers1

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I've managed to get a successful print! The key was to keep the material moving quickly. The settings I've customized are as follows:

  • Print Speed: 70 mm/s
  • Layer Height: 0.4 mm
  • Default Printing Temperature: 215C

...and perhaps not as necessarily:

  • Shell Wall Thickness: 0.8 mm
  • Wall Line Count: 3
  • Alternate Extra Wall: True

Also, I've found it important to print a skirt (perhaps a double-walled one), and watch the first-layer closely and be willing to push more material through and restart: The material in the hotend can easily form a partial clog while the printer runs through its auto-leveling / head-cleaning routine, thus needing to have more material pushed through before the job starts in earnest.

By the way, the model is https://www.thingiverse.com/thing:1993747, by Holodrio on Thingiverse.

Successful print with Entwined

Charles Duffy
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