I present my Tritium Ear Stud, for use with a 1.5x6mm tritium vial (tritium vial not included).
The pin is 1.2mm thick and is designed to be used with my Plastic Butterfly Retainer. The pin has support material on each side, which will need to be removed with a fine saw or dremmel type tool.
The tritium vial should be set using a UV activated optically clear adhesive such as Norland 61 or Loctite glass bond. These adhesives will cure in direct sunlight in an hour or so.
Before gluing, please ensure that the vial fits loosely into the stud slot and that there are no tight spots. Due to potential irregularities in the printing process, some gentle filing may be required on the tritium vial slot, to ensure an unobstructed fit of the vial, into the stud.
I have a few assembled tritium items available from my Etsy shop (tritium vials glued in place with Norland 61 and split ring installed).
There are some more photos of this object and other examples of my work, both 3D printed and otherwise, on my 'Tofty' facebook page.