I designed this Trim Potentiometer adjustment tool for adjusting a variety of different trimpot models, and it should fit most trimpot barrels.

This is the second version. There was nothing wrong with the first version, which is much smaller, but there were requests to have one with a knurled knob at the end for more fine-tuning adjustments. 

It is intended for use at a nuclear power plant, where Foreign Material Exclusion is a major concern, so it is also intended to float for easy retrieval should it be dropped into water. 

Features:

Inset flathead tweaker

Floats

Lanyard loop

Knurled Knob

Indexing points on the top and near the tip to help align the flathead with the recess in the pot.

Printing Recommendations:

Do not use supports. This will fill the internal hollow space meant to keep it floating. Necessary supports are designed into the file.

Filament: This should be printable with just about any filament other than TPU. 

Walls: 2+

Infill: Doesn't matter, it will be all walls anyway. 

USE ARACHNE WALL GENERATOR SETTINGS. "Detect Thin Walls tends to some structures not printing well. 

Post Processing:

The designed in support fin below the tip should snap off, but may be on a little more tightly and need to be cut off.