I just finished making a head tube badge for my bamboo bike today. Thought I would share the results.
I found a tutorial on another forum (google search "custom head tube badge Bulldog") that went through the process of selecting the jewelers saw/blades and the thickness of metal sheet. I used a #2/0 blade, and some brass sheets.
I found a graffiti stencil and used that for the design template.
After clear coat: