shawnbc84
Posts: 2
Joined: Mon Feb 06, 2017 4:30 pm

Brim and Skirts Woefully Under Extruded

Mon Feb 06, 2017 4:35 pm

Hello There:

I am printing some small-ish parts. They aren't thin wall, but are still small enough that a brim would work best with the part.

My problem is that my brim and skirts are printing very under extruded. There is visible gaps inbetween the individual lines. However, when it gets to printing the actual part, the extrusion is normal.

What setting do I need to tweak to toughen the brim and skirts up so they fully extrude?

At this point I do not effectively have a brim option because the thing is so flimsy it is pretty much the consistency of human hair, and does not serve the purpose I need.

Thanks!

brian442
Posts: 1243
Joined: Mon Nov 28, 2016 5:35 am

Re: Brim and Skirts Woefully Under Extruded

Tue Feb 07, 2017 6:09 am

Maybe add a few more skirt outlines so that the extruder has more time to prime. If the extrusions are truly like a piece of hair, then the nozzle clearly isn't fully primed yet.

You can also try manually extruding 100mm or so of plastic before the print using the machine control panel to make sure it's ready to do before you start the print

shawnbc84
Posts: 2
Joined: Mon Feb 06, 2017 4:30 pm

Re: Brim and Skirts Woefully Under Extruded

Tue Feb 07, 2017 1:40 pm

brian442 wrote:Maybe add a few more skirt outlines so that the extruder has more time to prime. If the extrusions are truly like a piece of hair, then the nozzle clearly isn't fully primed yet.

You can also try manually extruding 100mm or so of plastic before the print using the machine control panel to make sure it's ready to do before you start the print
Hi Brian!

Thanks for the thoughts.

I thought the same thing as well. However, I have done two things to rule out a improperly primed print head:

1. Added a ludicrous amount of lines to the brim (im talking 20 at one point). The same result happens.
2. I added a 10 mm extrude and wipe to the gcode at the beginning of all prints.

Also, if it were improperly primed the part wouldn't immediately start printing correctly, it would have *some* length of whisp in its first layer, and it simply does not. It is ONLY the brim/skirt that is giving me the problem. It is strange and perplexing.

brian442
Posts: 1243
Joined: Mon Nov 28, 2016 5:35 am

Re: Brim and Skirts Woefully Under Extruded

Wed Feb 08, 2017 5:10 am

Maybe the nozzle is too close to the bed so that there isn't room for any plastic to come out. Try increasing the first layer height to 200%.

mr.sneezy
Posts: 18
Joined: Mon Jul 16, 2018 11:41 pm

Re: Brim and Skirts Woefully Under Extruded

Wed Dec 12, 2018 11:57 pm

Did the OP resolve this problem ?
I have a similar one. Brims are printing the right thickness in Z (0.3mm in this case) but the lines are thin width wise and not touching each other in sections (so the brim is not functional), but the first layer of the print object goes down fine and maybe even slightly too much extrusion.
Also, trying the same print with Slic3r produces a normal density brim, same as the print object.
In both slicers I use a 15 loop brim, so it's not about nozzle priming.

It's like the brim has it's own flow rate trim someplace...

gwhite
Posts: 126
Joined: Wed Jul 19, 2017 9:37 am

Re: Brim and Skirts Woefully Under Extruded

Thu Dec 13, 2018 8:27 am

I've seen similar issues with skirts. This was mostly with 4.0. I just switched to 4.1.1, and I think it's still an issue.

I assumed the extruder was just getting rev'd up, but increasing the number of passes didn't help. I lower the first layer thickness & cranked up the over extrusion on the first layer, and if didn't seem to do much. I also get the same issue with sequential parts where the skirt isn't fusing together even on the last print.

I haven't needed brims, so it doesn't really affect my prints, but it's puzzling.

S3D-Jake
Posts: 753
Joined: Wed Jun 20, 2018 12:45 pm

Re: Brim and Skirts Woefully Under Extruded

Thu Dec 13, 2018 9:27 am

Good discussion, guys! In 4.1.0 and 4.1.1 the first layer height setting will now actually lower the extrusion amount proportionally to the percent below 100 you set in the layer tab. In prior releases, you would've seen that the extrusion amount never went below 100%. This was previously done to aid users in the ability to "squish" the filament for a better bonding on the first layer.

Now you can accomplish the same effect by setting first layer height to 100% and then using the Global G-Code Offset on the Z-Axis in the G-Code tab to once again achieve that nice "squish" effect from before.
"A bird does not sing because it has an answer. It sings because it has a song."

gwhite
Posts: 126
Joined: Wed Jul 19, 2017 9:37 am

Re: Brim and Skirts Woefully Under Extruded

Mon Dec 17, 2018 9:11 pm

Thanks for the tip, but "First Layer Height" really shouldn't mess with the extrusion. As you say, this is normally used to add "squish" to improve adhesion to the bed. Automatically undoing that behind the scenes and then having to apply a non-intuitive fudge factor elsewhere strikes me as a step backwards.

I was having pretty good luck with 4.0, and spent several days of ruined prints due to poor bed adhesion. I've seen a sudden flurry of issues with 4.1.1 posted. I'm sorely tempted to revert back to 4.0.

S3D-Jason
Posts: 302
Joined: Sun May 31, 2015 6:01 am

Re: Brim and Skirts Woefully Under Extruded

Tue Dec 18, 2018 4:21 am

You can also try increasing the first layer width. That will help provide extra extrusion on the first layer.

As others said, it would also be good to set the first layer height to 100% (especially if you had it at a lower value), then use the G-Code Z-axis offset if you need to adjust the position of the first layer (for example, a value of -0.1mm would move the nozzle 0.1mm closer to the print bed for the first layer).

wirlybird
Posts: 1238
Joined: Sun Jul 17, 2016 1:32 pm

Re: Brim and Skirts Woefully Under Extruded

Tue Dec 18, 2018 8:03 am

S3D-Jason wrote:
Tue Dec 18, 2018 4:21 am
You can also try increasing the first layer width. That will help provide extra extrusion on the first layer.

As others said, it would also be good to set the first layer height to 100% (especially if you had it at a lower value), then use the G-Code Z-axis offset if you need to adjust the position of the first layer (for example, a value of -0.1mm would move the nozzle 0.1mm closer to the print bed for the first layer).
Wouldn't increasing the first layer width also increase the spacing between the extrusions so it would actually not help?

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