What setting do I need to change to get rid of this gap between the shells and the inside?

4

I've noticed that some of my prints (mostly square-ish objects) are coming out with gaps between the outside shells and the inner parts. This gap is visible even in the 2D sliced preview of the layers so I think it must have something to do with slicing settings, but I'm at a loss for what I need to change to fix it.

See below for images of the issue. On the orange piece near the right hand side you can see light shining through the gap. The black cube has it at the top, though it's not deep enough to let light through like with the orange one. There is also an image of the layer preview which shows the same gap.

I have a Rostock Max v2 (stock hot end). I am using Matter control using mostly stock settings, I've tweaked around layer height, speed, and temp but I don't think those are the cause.

.

Images of the issue:

enter image description here enter image description here enter image description here

FoamyGuy

Posted 2016-05-08T14:30:46.043

Reputation: 143

2Hi, FoamyGuy! I edited your post by adding the images you refer directly to the post. This way, you don't need an additional click to see the issue, and the images will be available even if the link goes bad. – Tormod Haugene – 2016-05-08T17:36:18.850

@TormodHaugene ah thank you. It slipped my mind that you could embed them. Thank you for bringing them in to the question. – FoamyGuy – 2016-05-08T20:52:21.007

Answers

2

It's generally called infill overlap. In terms of first layer it's good to set extrude rate to 120% or even more so infill will overlap perimeters and itself. There is also the issue of "overlapping" layers which is not managed by any specific parameter. it's the issue of layer thickness and HE temperature.

Unfortunately Matter Control has kinda bug or at least an issue with extrude rate. If you set higher extrude rate then overlap will be automatically reduced in some way. So it's good to increase extrude rate manually during printing and then set it back to normal. this will cheat slicer.

darth pixel

Posted 2016-05-08T14:30:46.043

Reputation: 3 363

Ah! Thank you. infill overlap was set to 0.1. I bumped it up to 0.3 and at least on the layer preview there are no longer the big gaps visible. I'll try a test print to see how it comes out. – FoamyGuy – 2016-05-08T16:02:22.080

Ok, the test print is finished. using 0.3 did remove the gap between the infill and the shells. As you noted, it seems to be somehow tied to the extrude rate setting. Even though I didn't change rate it seems to be extruding slightly less now. Maybe I can find some happy medium with them.

How would I manually increase the extrude rate? Edit the gcode file that comes out of the slicr before letting it run on the printer? – FoamyGuy – 2016-05-08T16:35:39.273

@FoamyGuy On the bottom of control panel there are two sliders. One drives print speed and second drives extrude rate. These two canbe set during print. This is what i meant to say. Good to here you've managed the problem. – darth pixel – 2016-05-08T19:24:01.213

Oh, Thank you. I see those now. I'll give a shot here a bit later. – FoamyGuy – 2016-05-08T20:52:59.553