OpenSCAD programs for designing and building uv and vis spectrometers.
More information and links to YouTube video demonstrations at SmokyMtSci.com. Compatible optical elements and electronics for building uv and vis spectrometers can be purchased from this source as well.  

OpticsCalc1 program is used to define the geometry of a Crossed Czerny-Turner spectrometer body. Users can input parameters like the wavelength range desired, the number of lines per mm for the grating, the focal lengths of the mirrors used.  Running this program outputs position and angle parameters into the OpenSCAD Console pane.  

The Whee-UV-vis program is used to generate STL files for 3D printing spectrometer bodies and lids.  This program requires the user input location and angle parameters for the various optical elements.  These parameters can be copied from the Console pane of the OpticsCalc1 program.

The programs assume one is using the optical elements available from Smoky Mountain Scientific.  That is, the optical slit, mirrors, and electronics.  Mounts for these optical elements can be 3D printed from stl files available from a separate repository.  Alternatively, you may download the OpenSCAD file from here and modify the designs to match optical elements that you currently have.

Good luck-
Jack