Achieving constant number of perimeters
Hello, I'm currently struggling with a new project and I hope you guys can help me to get things work.
I'm working on a lamp with different spherical lampshades. Due to the spherical form, Prusaslicer puts more perimeters in the steep regions than in the rest of the sphere, to keep the wall thickness even. This leads to several quality problems. So, my question is:
Is there a way to achieve a constant number of perimeters over the whole print, without having infill? im clear, that the wall thickness will become uneven, but that's not really a problem.
RE: Achieving constant number of perimeters
My guess is that you need to design the model so that it has the correct horizontal wall width for your wanted number of perimeters a at every layer, but I don’t think you can print a sphere that way, it would need an open top and bottom from a certain angle where the horizontal width across the wall becomes greater than your desired number of perimeters. The slicer will only try to produce what is modeled. The exception is maybe vase mode but then you are limited to a single perimeter.
/Anders
RE: Achieving constant number of perimeters
The Spheres are cut on the top and bottom to get a maximum overhang angle of about 50°. For a simple Sphere, your described way may be suitable. But these spheres are much more complex in terms of surface structure.
RE: Achieving constant number of perimeters
Can you save a prusa slicer project file with an example please (File>save project as). Take the 3mf produced, ZIP it up so the forum will accept it and attach it to a post here.
RE: Achieving constant number of perimeters
If the desire is only to have the number of perimeters the same along all the z layers, What you might want to do is find the layer that has the most number of additional perimeters, count the total perimeter count and change the perimeters for the entire object. I haven't had this issue, myself, but if I did this would be one of my first attempts to address the issue.
If you want to force the entire model to have, say, 3 perimeters you may be out of luck. I haven't seen your object, but if the slopes are too steep then below a certain number of perimeters you will get some layer's perimeters unsupported by the previous layer (which is why PrusaSlicer adds perimeters in those places).
See my (limited) designs on:
Printables - https://www.printables.com/@Sembazuru
Thingiverse - https://www.thingiverse.com/Sembazuru/designs
RE:
@per-form-3d
Have you tried (Disabling) "Ensure vertical shell thickness:" ?
From there you can potentially use different Extrusion Widths and Layer Heights to gain purchase for the layers that need it. This will most likely affect in some way how the available light penetrates the model, however you may be able to adjust that to acceptable levels depending on material type & model shape.
This Thread is older but I believe it may hold some very useful information to help you with your project.
How to improve angled/overhang prints
Good Luck, I hope this helps.