Update 5/5/2019 - Added "Universal" flashlight mount, and Picatinny rail adapter. Also fine-tuned the hex nut hole and block size for better fit.
This is a flashlight mount for the Sig Sauer P365's proprietary accessory rail. It is designed specifically for the Olight i1R EOS LED keychain flashlight, which is small enough to be practical for the P365. This mount grips the flashlight on only the back half, so the front half can be rotated for dim/bright/off settings. Also, the front half can be screwed off to access the built-in USB connector for recharging the battery without removing the flashlight.
A generic mount, for many sizes of flashlights and laser pointers. Useful for testing options. Mount the flashlight with plastic cable ties through the rectangular holes provided in the mount.
An adapter from the P365's proprietary rail, to a standard Picatinny rail. Useful for mounting many standard options. I've tuned the rail's slot positions so that a MantisX training sensor mounts backwards on the rail, tight against the trigger guard, leaving the charge port accessible from the front.
For all parts, two halves (Left and Right) must be printed, then mounted using a 2.5mm socket-head cap screw and nut. Cap screw lengths needed:
- Flashlight Mounts: 15mm or 16mm
- Picatinny Adapter: 12mm
The screw and nut are not generally available at hardware stores, but you should be able to get them from a hobby store (like a model RC store for model cars and planes) - for example, Du-Bro SKU 2119 and SKU 2104.
Gray or Black
Using Cura, I find it easiest to just print the Left part, then use Cura's Mirror option to generate the Right part for immediate printing. If you rather, I've included a FreeCAD generated Right STL file, but it probably needs to be flipped for printing.
SUPPORT NEEDED for Picatinny adapter - No supports needed for either flashlight mount.
For the Picatinny adapter, I found the following support non-default (Cura) settings to work fine, and allow the support structure to be easily removed:
- Support Density - 15%
- Touching Build Plate - Enabled
- Support Overhang Angle - 50 degrees
- Pattern - Zig Zag (default)
Rail Mount Base with Flashlight Payload Below
FreeCAD Design Notes
This design was an exercise in creating a modular component so that the complexity of the P365's proprietary rail could be re-used for mounting different component designs. I also wanted to make most designs easily printed without supports, and allow mirroring of the part for two halves that could be mounted to the P365 with a single bolt.
The various angles and cuts required for the rail are therefore built as one "standard" component, as a rail "base" as shown by the gray part in the image above. This part (included as a separate FreeCAD file "P365_AccessoryRail_Base") can therefore be used as a foundation for the mount without modification. This base is divided from a custom "payload" component, by the XZ plane. The "payload" part that can be customized can then be built upon the base, starting with a sketch on the XZ_Plane and building in the opposite direction from the base - see the flashlight mount part in light green in the image above.
As an example, the flashlight mount was started as a simple block, padded out from a rectangle on the XZ plane, using external references from the Base rail component edges. This block was then "sculpted" with a pocket sketch drawn on the side of the block, to form the cylindrical cut-out for the body of the flashlight, including the 45 degree slant cut on the bottom side (see light green component above). A little fine-tuning by creating a pocket sketch on the front of the original base component finished out the part.
I used the Base file as a platform for both the flashlight mounts. However, to keep the Picatinny rail as compact as possible, I had to integrate the screw hole into the design. Thus I extended the block at the bottom of the base design, then "sculpted" the Picatinny rail as a subtractive pocket sketch directly on that extended base.
You are welcome to use the Base file to create your own custom parts for a P365 native rail. Please let me know what your imagination comes up with!
Note that mirroring of the part can be done either in your slicing software (Cura has a feature specifically to do this with any .stl file), or within FreeCAD. I included separate right and left .stl files for each part, generated with FreeCAD (you may need to flip one for printing). To generate a mirrored .stl file in FreeCAD, just select the Body of your component, then in the Part workbench, use the Mirroring a selected shape button to mirror the full design. Then select one of the body components (either "Body" or "Body (Mirror #1)"), then File > Export to export it as an .stl file. Repeat for the other body part for the mirrored part.