This object is a Dekatron escucheon ring.
While i have seen these on sale, ebay etc.., they have been very pricey. This one has been in the works for a while, and i finally have something i can let out of the lab!
The ring as designed is for GC-10B tubes, 29.5mm diameter, but the first ones printed , pictured here, fit the OG-3 OG-4 snugly, You can probably scale them as desired.
See http://www.thingiverse.com/thing:424067 for a tube holder.
For info on dekatrons..
Definition of ESCUTCHEON
: a protective or ornamental plate or flange (as around a keyhole)
Print this without support, face down.
The pictured print is in PLA.
The lettering is printed as a void, which i filled carefully with a "polymer clay" product. (Look for it in the craft stores). The clay i used has to be baked, mine at 110 degrees C.
The heated print bed was used, set to ABS.
For what it's worth, i use a cover on my print bed composed of a lot of layers of a mylar "space blanket" "tacked together". for an insulation layer. It also helps the print bed pre heat evenly and retain the heat till ready to print.