I am not a photo buff by any stretch, but I just bought a vintage Kodak Instamatic 404, and had been reading how the film format for these cameras was dicontinued in 2007. People ask me all the time when I show them my 3D printers, "What's it good for?"
Now I have an answer! This project/Work-In-Progress aims to re-engineer the form factor of the 126 film cartridge, and provide the building blocks for creating an easily rechargeable film adapter, and other gizmos for these cameras.
This project needs information more than anything. I've found the patent for the cartridge, with decent drawings, but no measurements. These are contained in a withdrawn ISO document. I suppose this mean it is generally not available. Google turned up very little.
I have purchased two cartridges on eBay to take measurements from. The plan now is to model a printable shell, and takeup spool so I can load fresh film into the camera. The film inside these cartridges is essentially 35mm, with a couple of differences. The registration holes, and chemistry. The spacing of the registration holes usually requires that you take three "covered" exposures for every shot, in order to advance the film and avoid overlap.
This feature does present the opprtunity to creat a type of panoramic camera if I adjust the exposure window of the cartridge, making each exposure narrow, and tall.