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Is there no other way? I don't want to download a 95MB installation file, which is Autodesk property.
I installed this MessyMixer and tried to split in two parts the original "assembly_body_middle.stl", which has the filesize of 32MB.
Surprisingly I get first repeatedly a warning message "...mesh manifold too complex" or something like that and the the resulting STL files have the size of +80MB each (+160MB in total). Sorry, but for simple shapes I expect a simple light-weight solution.
BTW, out of curiosity I tried to split other STL files with MessyMixer and it works fine, even if it generates far too many meshes. So, my conclusion is that the original STL file should be geometrically well defined and saved in a rather small filesize. When I inspect all STL files for this Sveedish Rc-6 locomotive, the most problematic file to split is "assembly_body_middle.stl". Any workaround solution?