CHRISTOPHER N&W----> Thank you for your comment! rendez-vous on the other thread!
RAILRIDE---->I had not understood why your post had been deleted and who had done that!!
My 3D drawings are made with SKETCHUP Make (the free version); if you want to convert the files for 3D printing (.stl files), you have to download a plug-in via the SKETCHUCATION website. That's all. No need to have the "pro" version.
jpv in France