This design is a device that uses the thermodynamic properties of pressurized difluoroethane (in Dust-Off cans) to make a wrist-mounted liquid difluoroethane sprayer. The basic idea is that, due to the rapid decrease in pressure, temperature must also drop. This is why a can of Dust-Off feels cold after prolonged use. By holding the can upside down, liquid difluoroethane (and some other cold gasses) are released.
The whole thing (including the moving arm) can be printed as ONE PART, even on an FDM printer, due to custom designed tolerance.
Ergonomic: Made to fit my forearm snugly. However, because it is custom designed, it might not fit everyone perfectly.
Completed four iterations of the design in order to achieve my own satisfaction.
Step 1: Print and Enjoy
Simply download the .STL file, and print on any 3D printer. If printed with support material, it should snap into motion. Then, add straps and slide it on. Hold upside down, depress the lever, and enjoy a stream of liquid difluoroethane!