I like to make pared down pens every now and then just to focus on form and design aspects. Here is one I made from transparent acrylic, with silver trim. It’s based on a 13mm diameter cap thread, and is about 5.25” long. It uses a jowo 6 nib.
Drill SLOWLY with plenty of lubricant and sharp bits.
sand the interior from 320 to 1000, then through all the Zona papers
Polish using the magic juice compounds.
Then possibly repeat a couple more times, because you’ll undoubtedly find some scratches you missed.