Octagonal Fountain Pen

Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4896665.

I messed up my Pilot Metropolitan trying to forced patina it, so I made a replacement.

It has a M10x0.75 thread, which accepts Pilot Metropolitan and Custom 74 nib sections and probably others.

Print thread1 and thread2 and check if they fit before printing the whole thing.

The cap and barrel might not align perfectly, just twist it until it aligns.