Originally I just set out to make a dumb EF mount so I can use my one canon lens with my Epic. The project ended up with FD mount, a PL mount, and on top of that directors viewfinder.
The EF and FD mounts themselves are metal and salvaged from old broken 35mm film cameras, by printing a base for these mounts I can use it with the Red Epic. Flange focal distance is very close to where it needs to be, and for fine tuning adjustments I'll just have to spend extra time adding shims between then mounts and the printed base.
After salvaging the parts from the cameras, I realized I could print an enclosure using the viewfinder parts of the camera and make a directors viewfinder. After several attempts I was able to get the positioning of the plastic "ground-glass", penta-prism, and viewfinder lens just right. It only made sense to use the same mount as the Red Epic, that way I can easily use any mount on either of them:-P I also made inserts that can be fitted in through the front that basically frames up for the actual sensor size used. So with this directors viewfinder, you can see exactly what you'll see in frame as you would on the camera.
Overall, everything works surprisingly well. A few tweeks here and there and it's golden:-)
3 of the attached images below were shot on my Epic with one of the printed EF mount using my Canon 18-55 EFs lens and 1 was with a Canon 50mm FD lens:-P
So I've made more than one.... Anyone interested?
(4/23/15) Update: Available now through my webstore! http://fuzeti.com/camera.html