.stl file exported is not smooth

[Lovesuiyuan]

I use the latest FreeCAD 0.17, now I import a step file, then export stl format file.but when I open the stl file exported, I found the model surface is not smooth, I can see obvious edges and corners.
Then I use another 3D software to deal with the same step file, the stl file is very smooth.

other 3D software export file effect as follows:

oherSoftwareEffect

otherSoftwareEffect.png (171.1 KiB) Viewed 6126 times

FreeCAD export file effect as follows:

FreeCAD stl file effect

FreeCADEffect.png (162.99 KiB) Viewed 6126 times

Please Help, so, what should I do to improve the surface effects, any suggestion is appreciate!!

[bejant]

what should I do to improve the surface effects,

Hi Lovesuiyuan, and welcome! You can get smoother surfaces in the .stl Export by using the pull-down menu and changing Edit > Preferences > Part Design (icon in left pane) > Shape view (tab at top of right pane) and changing the "Maximum deviation depending on..." setting from the default setting of 0.5 % to something smaller.

A lower number will make smoother surfaces when the file is Exported to .stl., but the file sizes will be larger. Objects in the 3D view will also appear smoother on your computer monitor, but it will take FreeCAD more time to display them. On complicated models this might make FreeCAD too slow, so after Exporting the .stl you might want to change that "Maximum deviation..." setting back to the default.

(edited typo)

[HarryGeier]

I guess.. you chosse the wrong way or the wrong mesher to create the STL..

look at the end of this video to see how i export STL and they look smooth ...

https://www.youtube.com/watch?v=rgstQi9jpGc&t=280s

[jmaustpc]

If you convert a solid to a mesh in mesh workbench you will get more control over the triangulation of the resultant mesh than simply exporting as stl. Exporting as stl does so by reading the opengl display triangulation, which is why bejants suggestion works.

[jmaustpc]

Another tip, don't forget that stl is a lossy format that by definition is impossible to convert properly back to a cad solid format like step etc. Stl has its uses as an output format, but from a cad point of view is a garbage format.

[oldmachine]

Change the Tessellation value in the export pref's panel - that is what controls the smoothness...

[sgrogan]

Hi Lovesuiyuan, and welcome! You can get smoother surfaces in the .stl Export by using the pull-down menu and changing Edit > Preferences > Part Design (icon in left pane) > Shape view (tab at top of right pane) and changing the "Maximum deviation depending on..." setting from the default setting of 0.5 % to something smaller.

For .stl .obj and .amf this is no longer true.
The Shape view only effects the display tessellation in FreeCAD.
The default export tessellation is controlled by Edit > Preferences > Import-Export Mesh Formats tab.
You need to activate the Mesh Design workbench first for the preference option to be available.
This was done so a coarser tessellation can be used for display to keep the FreeCAD gui responsive and to be able to export a very fine tessellation without switching the Shape view preference back and forth.

[Lovesuiyuan]

what should I do to improve the surface effects,

Hi Lovesuiyuan, and welcome! You can get smoother surfaces in the .stl Export by using the pull-down menu and changing Edit > Preferences > Part Design (icon in left pane) > Shape view (tab at top of right pane) and changing the "Maximum deviation depending on..." setting from the default setting of 0.5 % to something smaller.

A lower number will make smoother surfaces when the file is Exported to .stl., but the file sizes will be larger. Objects in the 3D view will also appear smoother on your computer monitor, but it will take FreeCAD more time to display them. On complicated models this might make slow FreeCAD too slow, so after Exporting the .stl you might want to change that "Maximum deviation..." setting back to the default.

Thank you very much.I use your method, and it works, I get smoother 3D file. it solve my big problem, Thank you again!

[Lovesuiyuan]

Thank you for everone, especially bejant.It can be solved by using the pull-down menu and changing Edit > Preferences > Part Design (icon in left pane) > Shape view (tab at top of right pane) and changing the "Maximum deviation depending on..." setting from the default setting of 0.5 % to something smaller.

[bejant]

The default export tessellation is controlled by Edit > Preferences > Import-Export Mesh Formats tab.

I've never tried that method, but like that it doesn't change the display....

Thank you very much.

You're welcome, and post back if you need more help.