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Slicer Shell Thickness vs. Model Shell Thickness


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Posted · Slicer Shell Thickness vs. Model Shell Thickness

Newby, still trying to fit all the pieces together.  Working on a particularly irksome print and trying to understand how Cura settings interact with the dimensions of my model.


So, the key question for me is:  If I have a hollow model, with a wall thickness of 2mm, and I set the Cura shell thickness to 3mm, what happens?  Will Cura override my model dimensions or adhere to them?  Or, will Cura just go off on a tangent and do something weird?


If I can get this straight I'll have a much better idea of how to set up my model in Cura.

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    Posted · Slicer Shell Thickness vs. Model Shell Thickness

    There are exceptions (different topic), but in general the slicer does not change the model but tries to calculate the toolpath in a way that it stays as close as possible to the given mesh geometry.


    From the perspective of a slicer, a "wall" in the model always consists of two "shells": inner and outer shell. That's one of the reasons why it is so important that the model has to be "watertight" and must not contain any additional faces inside of solid walls.


    Depending on the line width and the shell thickness the maximum number of "wall lines per shell" is calculated.

    • If the wall of the model is thinner than the two "shells", the line count is reduced and the whole wall is printed with a proper amount of "wall lines".
    • If the wall of the model is thicker than two times of the "shell thickness" the gap in between the "shells" will be printed as infill (or "gap fill" if the gap is small and if the according option is enabled).

    You can always check the generated toolpath in the "Preview" before printing, that's the best opportunity to compare different settings visually (although... i guess you already know this).


    Hope that helps!


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