Status: Parts produced
Presentation
The goal of this project is to build a replica of the M-94 device that could be used to decipher actual M-94-enciphered messages, and make it as close to the original as possible while remaining economically feasible. For this reason it will be mostly 3D-printed, with some metal parts.
The first step is extensive research to ascertain the shape and dimensions of every part, for an accurate reproduction.
The device can then be modeled.
Parts are 3D-printed, tested and adapted if necessary.
Necessary metal parts are machined or outsourced.
3D modeling
The device is composed of the following parts (for a more precise description, see Technical infos):
- 25 discs, each with a different alphabet on its rim
- A shaft with a knurled flat nut at the left end, and threaded at the right end
- A left end cap
- A right end cap with a straightedge
- A thumb knurled nut
A stand is also designed.
Name plate
3D printing
The small size of the disks makes it a challenge to achieve a good quality with 3D-printing, so several methods were tested, with various results.
- Metal-filled filament
The initial goal was to use metal-filled filament, so the object looked better and felt heavy and cold like the original, but this never yielded satisfactory results.
- PCTG
Another attempt was made with PCTG, which allows the use of a smaller nozzle compared to metal-filled filament.
A few discs printed with Fused deposition modeling
The results were decent enough but it appears this is pushing the limits of this method; the discs may be too small to be printed with acceptable quality on a filament printer.
- Resin
The next attempt was with resin printing, which allows a better resolution.
Both sides of M-94 discs printed with resin
The resulting parts look very good, although they lack the heavier feel that was hoped for with metal-filled filament.
- Metal
Finally, metal 3D-printing was tested.
M-94 disc printed with metal
The results look great, the parts are even heavier than the original.
The cost is of course many times that of the other methods, and making the entire device with this method would be very expensive.