Here are all of the files needed to use my process of making 3D printed screw threads. There is a description of the post printing process on Thingiverse here , but if there are any questions, please feel free to get in touch.
All of the stl files
These files you can send directly to a 3D printer. After it is cast and fired, the cap and lid will be slightly larger than the top of a soda bottle, depending on the clay shrinkage.
This is the Fusion 360 File
This file requires Autodesk Fusion 360. Here you can see how I made the models, and it includes optional cottles and slugs for the silicone master moulds.