Focus Tab lever for Voigtlander 28mm Ultron F1.9 lens in Leica M mount

Two different focusing knobs for Leica M-mount Cosina Voigtlander 28mm F1.9 Ultron lens:
 

1. Mandler Tab  (my favorite)
   Designed after the Mandler-era Leica lenses from the 1970s through 1980s such as the 35mm Summciron V4, or 50mm Summicron V4.  Shown in photos.
    
2. Modern Leica Tab
   Modeled after the 28 Elmarit ASPH V2 focus tab.  This tab is slightly longer so lens and body will not sit perfectly flush if tab is facing directly down.  Not shown in photos.
    

Both of these are designed to be attached with 3M Clear VHB tape.  It is a sticky silicone-like tape that is removable without leaving adhesive.  

I used 3M clear VHB tape carefully trimmed to fit the focusing knobs.   The tape is hard to trim but is possible with patience and the right technique.

Other double sided mounting tapes may be easier to deal with.  Foam tape is probably simpler to use, but I used what I had on hand.



Printing
Printed on Ultimaker 3 at .2 layer height with PLA, however serious users should consider a UV / heat resistant filament such as Nylon or PETG or ABS.



Future Versions
I will be making an adapted version of this that also includes a proper hole so these tabs can be screwed into the body in place of the original baseball-bat style focusing knob.