Here you can find exactly 100 technical drawings (pdf, ISO standard) with correspondingly 100 pictures (jpg) for 100 mechanical parts. They are ordered by complexity from easy to difficult and summarized in the drawing All 100 Parts (pdf).
You can use this PDFs and JPGs to practice modeling with any 3D CAD software, from AutoCAD to Autodesk Inventor, SOLIDWORKS, CATIA, Creo Parametric etc..
Copyright Precautions: You can freely download all this 201 files, print and use them for yourself. If you want to use them in order to earn money by any means (publications, courses, training a.s.o.), then you must mention the source (Prof. Constantin STANCESCU) and send a courtesy message on the address email@example.com.
Here are all 201 files (mostly zipped):
Summary - All 100 parts.pdf (to be printed)
Important: All 3D parts from this Album modeled by the author with Autodesk Inventor can be find on the site GrabCAD.com starting with this one: https://grabcad.com/library/parts-001-010-the-cad-album-of-100-cad-parts-1