Overlap mesh applying the fuzzy skin to the inside of my print, not the outside

[philippeholthuizen 0]

Hi All,

I'm still using Cura 5.0 because that offers the best and most stable combo of things I need to work.

I'm trying to use the overlapping mesh modifier, infill mesh only, to create size numbers on the footbed of my shoe designs.
I had hoped to use 'Horizontal offset' with the modifier but that didnt work.
Fuzzy skin seemed the next best solution to use. It works, but not how I need it to work. It applies the fuzzy skin to the inside of my shape.
Any idea on how to fix that, is it because of the normal directions of my STL maybe?

Also of note, the the shoe design is an stl that combines several different watertight volumes. But Cura does not recognize 'it' (the assembly as one stl) as watertight.

See attached screenshots, hopefully they illustrate the problem well enough.

Any help would be appreciated, also for other methods on how I can easily add the numbers to my prints. I can do it in 3D CAD, but I'd like to find a more efficient and 'fewer files/parts needed' way.

Thanks oodles!

Philippe from FUSED

Edited August 29, 2024 by philippeholthuizen

[Slashee_the_Cow 621]

I'm rocking 5.8 here because 5.0 is a little too old (and a bit too new) to be in my testing arsenal.

 

If whatever you're using as a mesh to add the fuzzy skin is thin enough, it should only show on one side:

Obviously this is a problem if you want to put it somewhere that isn't flat. There is (at least in current versions) a Fuzzy Skin Outside Only setting:

But depending on your model it might not be able to pick an inside vs an outside and do it on both sides:

 

AFAIK the normals don't matter, it just works by adding random jitter to the walls after they've been sliced.

[philippeholthuizen 0]

Oh wow, interesting results! I guess I might give 5.8 a try.

So I'm not a fan of the cutting mesh because it 'breaks' the walls. But I see that your second example doesn't have that. What was the difference between the two? Just how thick the cactus shape was?

[Slashee_the_Cow 621]

Me and my bovine friend here object to her being called a "cactus"

But it does break the thing into sections... the fuzziness is just great at hiding it in this simple example (that's with the fuzziness appearing on both sides):

If it's only appearing on one side then it is still its own walls on the inside:

And it's fuzzy on the inside, but should still work fine:

But I'll admit, far from an ideal fix.

[philippeholthuizen 0]

Thanks Slashee! In the end, the best solution for me turns out to be a cutting volume that overlaps just 0.5mm deep into the object surface and has no walls, top or bottom. That comes out as just a depression in the 3D printed surface.