why my round surface are not round when i export my project as obj or stl file? When i open it with ultimaker cura or a other 3D program it is not round. I tryed it with 2 projects. Always when I export a round file it is not round and have many faces. What can i do?
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STL and OBJ are mesh formats and the geometry they describe consists of points, edges and triangles between them. You can make a finer mesh (small but more triangles) but in the end they will still be triangles. Default tessellation is governed by objects View properties Deviation and Angular deflection. Smaller values-finer mesh.
Above you will find an explanation about the two parameters cited by @kisoire, that you will find in the View Tab of an object. but only for visualization by the rendering engine, for exporting properties see below.
To tune deviation when exporting you must activate "Mesh Design WB" and under View >> Preferences >> Import/Export >> "Mesh Formats" you will find a "Maximum mesh deviation" value that is the only approximation that you could tune.
Regards
Carlo D.
GitHub page: https://github.com/onekk/freecad-doc.
- In deep articles on FreeCAD.
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Thanks for your help. It woks with the Mesh Design WB.
What i did:
open Mesh Desing WB -> selected the body from my object -> then Tessellate shape -> a new window is opening -> Standard Surface deviation to 1 µm or 2 µm and Angular deviation to 1° or 2°-> push OK ->now wait-> when it is done ->push Body (Meshed) in your model tree -> then Export a mesh to file -> give it a name -> save
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Try some different meshers, too. For example, netgen and different options: fine, extra fine, coarse, etc. You can switch to wireframe mode to better see the mesh created. (Shortcuts: V, 3 for wireframe: V, 1 to go back to normal draw mode.)
probably you have to lower your targets 1um is way too fine and generate a lot of points not needed for a 3d print the key is to set tolerance value when exporting 0.01 usualli will suffice. I usually export solids done using scripting so i set tolerance as a number in the exporting function.
More precision, more "points" more tessels bigger file and high processing times.
take in account that some 3d printer don't even have G2 and G3 to do circular interpolation, and you are limited by step x mm values of the printer.
Carlo D.
GitHub page: https://github.com/onekk/freecad-doc.
- In deep articles on FreeCAD.
- Learning how to model with scripting.
- Various other stuffs.
Iru wrote: ↑Fri Jan 28, 2022 5:09 pm
Standard Surface deviation to 1 µm or 2 µm and Angular deviation to 1° or 2°
This is probably way overkill, is there even a 3d printer with such a precision? do you even need such tolerance for the object? If it's just for the visuals, the layers will be much more noticeable than the tesellation, you can't see micrometers. Angle is also overkill. Try something like 0.1 or 0.05 and 10º. More complex models may take excessesively long to mesh if you use such a small tolerance.
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