OpenSCAD script for customised hangers.

The main parameters are the diameters and height of the recess (green in picture to the left) and shaft (yellow). I suggest making the diameters 1-2 mm larger than measured on the tool to be hung.

If needed a cone (purple) can be cut out between the recess and shaft. The width of the cone is determined by CONE_FACTOR and the shape can be changed with CONE_ECC (see below). 

The slit (blue) can be made narrower than the shaft hole to hold the tool firmer in place. But be sure to make SHAFT_DIAMETER-SLIT_TIGHTNING  wide enough for the actual shaft to avoid having to file the opening.

Screw hole placement depends on the height of the holder and SCREW_HEAD. At least WALL_THICKNESS is needed both above and below the hole for internal screws, otherwise wings will be needed. WING set to "low" makes wings at the bottom that will fit just one screw hole with margins, "full" makes the wings the full height of the holder with two screw holes if they would fit.

Be mindful to have enough clearance so that the tool does not lean against the wall, or bump into neighbouring tool on a multi-tool holder.