The only available new trim switches certified for use in a Piper Archer do not fit the original yoke cap. Initial attempts to create a modified cap with limited metal-working tools failed. Then I attempted a 3D printed new part, which worked great!
Not only did the switch have a rectangular barrel, but it was much
longer than the original switch. The replacment part has an integrated spacer that
allows the switch to fit without touching the inside of the yoke.
The 3D printed part was made with PETG plastic, which will allow it to withstand the temperatures
of a closed up airplane on a hot summer day in the sun.
Never skip an opportunity to print some rubber benchys!