I started out my career as a technical Illustrator in 1978 drawing Pen & Ink exploded parts catalog drawings for a logging tractor manufacture. In 1980 I started working for an Architectural/Engineering firm using Autotrol CAD software. Over the years I have used various CAD software, but am most familiar with AutoCAD.

Now that I am retired, I use as much free software as I can. I used the free version of DraftSight for a couple of years before purchasing the Pro version. I only needed the PRO version to be able to use some of my many Lisp programs I created over the years and also other lisp files that I could find that worked with little editing. DraftSight is not 100% Autolisp compatible. TurboCAD Deluxe I mostly use to convert STL files to DWG so I can work on the 2D geometry in DraftSight. TurboCAD Deluxe is a 3D modeling program in its own right, but I only use a few of its features. One thing I really like about TurboCAD is that if I explode a 3D object with the flat areas I want to profile, it will usually create the continuous Polylines that I need. I am still only using version 21 of the TurboCAD software. TurboCAD also does a nice job of converting to & from a few other formats like Sketchup files.

I use DraftSight to work out the 2D geometry of the 3D models & OpenSCAD to generate the final 3D objects. I am constantly amazed at how well OpenSCAD works. All the long linear_extrude code in my OpenSCAD programs is generated with a simple visual basic program I wrote to convert the X,Y listed data of polylines from DraftSight. I also wrote a simple lisp program to list that data to a text file.

I occasionally use Blender & Sketchup software. Blender I mostly use to decimate 3D objects that have way too much detail in them to work with or slice. I generally use a target length of .7mm for segments on curves when using OpenSCAD. If you look at a metric scale you will see that is a pretty small amount, yet I have seen quite a few models on here that have segments below .4mm & even below .1mm in length. That much detail might be useful if you scale the object up or use it for another purpose other than a plastic part later on, but just causes more time for the slicer & that detail will never be seen on a plastic part.