Learn AutoCAD with full-length video courses on SourceCAD, start your 7-day free trial https://thesourcecad.com/courses/ This tutorial will explain the most fundamental concept of 3d modelling ie using co-ordinates in autocad, without using co-ordinates in autocad you wont be able to make complex 3d drawings, the tutorial covers all the basic parts of 3d co-ordiantes.
for more autocad 3d tutorials go to http://www.thesourcecad.com/autocad-tutorials/
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