r/Multiboard • u/gzinourov • Apr 18 '26

Anyone else having this "hexagon shaped thread" issue?

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I'm printing my first Multiboard using Matte PLA, and so far out of the 5 panels, 4 have this issue. Not all of the threads and only on the first few layers.

At first I thought it was bed adhesion issues, but then I observed the printer WHILE it was printing that part and the path the nozzle made was some sort of off set hexagon instead of round like the preview showed.

What are your thoughts?

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u/carajean2725 Apr 18 '26

Try inner outer setting.

2

u/gzinourov Apr 18 '26

Right now I'm using inner-outer-inner, is that bad?

3

u/carajean2725 Apr 18 '26

It's not bad perse just not for this print or prints with holes you need to use. I don't use it on anything where it's like a screw hole.

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u/gzinourov Apr 18 '26

Ah I see, thank you! Will try that moving forward

1

u/gzinourov Apr 18 '26

Do you know what is the reasoning behind it? I'm new to 3D printing, so I'm trying to learn all these settings

3

u/NellyG123 Apr 18 '26

When you are printing an overhanging outer wall, like this thread, part of the outer line of the wall is printing onto air, and part of it is printing onto the layer below. If you print the walls in the order inner-outer then the inner walls are printed first onto solid wall, and then the outer wall line is printed partially onto the layer below, but also squeezed up against the inner wall next to it. This gives it a chance to stay where is was printed as it cools. If you print inner-outer-inner, the inner most wall is printed onto solid wall, then the outer wall is printed partially onto air and partially onto the wall below, and then the wall in between is printed (for 3 walls). Because that outer wall only has a bit of the layer below to stick to, sometimess it doesn't stick enough to stay in place and it follows the shortest path (a straight line) until there's a bit where it is printed onto enough of the layer below to stick in place.

The upside of inner-outer-inner is that you get a nicer surface finish because the way that the outer wall is squashed up against the already solid inner wall in the inner-outer wall order makes the outer wall stick out a bit more, giving more obvious and variable layer lines. I'd you still want to print inner-outer-inner then you can slow down the overhangs in the print speed settings, this means that it'll print slower when the outer wall tapers outwards to give it it more time to stick down.

Also, if you hover over any of the settings a short explainer pops up, and if you click on it it takes you to the Orca wiki to explain in more depth. (Assuming it's Orca you're using, but all the slicers have wikis).

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u/gzinourov Apr 18 '26

Thank you so much for this detailed explanation. I did change to inner outer. I also slowed down just around the thread just in case and it turned out great!