I use this for an airsoft gun, to mount a flashlight I bought at Costco (set of 3 for under $20). There are many other similar designs on Thingiverse, but I had trouble using some of the files for editing the design, so I just designed my own in Viacad.
The flashlight I used has a 29mm diameter, so standard 1-inch (25.4mm) scope rings would not work. 3D-printing to the rescue!
In case anyone wants to modify the design for their own lights, I have included the STEP file. I have never used STEP files, but Viacad can export them, so I hope it's useful. If not, there's not much I can do to help.
RR-picatinny_flashlight_mount.stl | 101.4KB | |
RR-picatinny_flashlight_mount.stp | 155.6KB |