3D parts files are generally split into two different categories depending on the application used to edit/create them. The two categories are either A) CAD files or B) 3D Modelling (or surface) files.
CAD files represent a part as the sum of multiple 3d objects that can be moved and/or manipulated so changes to the part can be made easily.
3D modelling files are represented using a surface mesh which upon which special effects can be applied. These files are generally used for computer animation and artistic purposes. They do not lend themselves to changes easily.
The official 3d files for Mendel are stored on sourceforge under the project name 'reprap'. To download all of them on a linux box, type in the following at the command line:
Tim Shmidt took the files on the sourceforge repository and rewrote them using openSCAD. He made them parameterized so you can adjust/tweak them. It appears this project is stagnant/dead as there were a handful of commits in Sept 2010 but nothing has been done with this since.
The code for the parameterized version of Mendel is hosted on Github at http://github.com/timschmidt/parameterized-mendel
The model is available in the following formats:
The CAD files for the wedge frame used in Mendel.
Please note this is not the same as Solid Works!
Available in Version 20, academic licence
All part files for the cartesian robot are available under 'cartesian-robot-m4' here. You will need to download the whole of 'cartesian-robot-m4', then search for the _SOLIDEDGE_README.txt for further instructions on opening the general assembly.
WARNING: some assemblies have been tainted by a careless user and many parts reference a folder in \\campus\files\MechEng\Research\General\AB\AB-0001 Manually repairing the SVN is time consuming and not reccomended at this time
AOI is a free, open-source solid modelling package. Model files have only been made for the individual printed parts, which can be found here. These parts are editable in AOI. There is no general assembly in this format. Advice on using AOI for RepRap can be found here.
Model files have only been included for the individual printed parts. These parts are not editable (not really anyway). There is no general assembly in this format.
Idaholion has translated Mendel into SolidWorks 2010 format, available here
The CAD files for the Mendel pinch wheel extruder are stored separately (see link bellow). These are required in addition to the wedge frame CAD files to build a Mendel. The standard extruder is described here.
Alternatives and Improvements
There are a number of alternatives and improvements to the standard Mendel design that are stored here:
See the README file at that location for an up-to-date list of what's available.
Many people have made sets of mendel-parts on Thingiverse that can be printed at once. Some with the smaller parts holding down the larger ones against warping. 2 Examples are here and here.
There are also lots of unofficial improved and corrected parts to be found on Thingiverse.