Hermes Baby Typewriter Knob with Guitar Knob collar

thingiverse

This replica of a Hermes Baby typewriter platen knob includes the exact number of ridges around the edge, modified to accept the inner collar and screw from a standard 1/4" guitar knob. This modification allows users to create a fully-operational knob even if they're missing the original metal insert. A cheap plastic guitar knob with a set screw will suffice; simply search for "chickenhead knob," as this type features exactly what's needed. Breaking it open, extracting the metal collar, and pressing it into the new knob completes the process. Printing supports in any orientation is necessary, but printing upright like a mushroom is recommended to achieve a smooth upper surface. 100% infill is also required. This design should fit on any typewriter (or object) with a 1/4" or less diameter rod. The center hole measures 8.8mm deep; the knob itself has a diameter of 25mm and a thickness of 8mm; the entire piece, including collar, is 14mm thick. A standard-spec knob without the guitar collar modification can be found at: http://www.thingiverse.com/thing:2134315