This knife uses regular trapezoid shaped razor blades, with 3 magnets allowing it to lock closed or open.
I designed this in solidworks, and converted the files to step files for anyone who wants to modify it.
I loved the original design, but I felt it needed magnets and all the holes were much too oversized when printed dimensional accurate, I also didn't have any M2.5 hardware and I don't trust machine screws threaded into plastic so I added nuts on the blade holder.
Here is a video of it in action: https://www.youtube.com/watch?v=vB86lOwQt8g