and thanks for fast reply !
I downloaded all the files from here : https://osf.io/besmf/
And also tried from here : https://www.youmagine.com/designs/open-source-completely-3-d-printable-centrifuge
No slicer used yet because I always check files before printing.
And these files have so many errors that there is no chance they can print well.
Just open them in Meshlab and have a look at the wireframe.
And the FreeCAD files are not really better...
I have no doubt that this centrifuge has been printed but I'm 99% sure it wasn't with the provided files.
Anyway I think it's a great design.
I will try to completely redesign it when I have the time.