Disassembly - Voigtlander 40mm F2.8 Heliar Vintage Line Leica M mount lens

Voigtlander 40mm F2.8 Heliar is one of smallest lens in the Vintage Line series and is beautifully crafted. This article shows how to access aperture chamber for cleaning and focusing thread surfaces for cleaning and lubrication.

Lens is so small, that even mounted on TTArtisan adapter it remains very compact on Fujifilm X-Pro3 camera.

Disassembly steps

Voigtlander 40mm F2.8 has mechanical construction optimized for compactness similarly to vintage Leica M lens. First step of focusing mechanics disassembly is to lock focus at infinity and then unscrew focusing limiter pin on the distance scale. However if you only want to access aperture chamber for cleaning - check the last step of this guide.

After that flip the lens and unscrew three black bolts.

Then accurately extract rangefinder couple cylinder.

NOTE: rangefinder couple cylinder has two pins on sides, they need to be accurately aligned when assembling lens back.

Flip lens facing up, unlock focusing and rotate focus ring until focusing knob reach "m" letter - at that location focusing thread is disconnecting. 

Use pencil or marker to mark radial position of most rear black ring, it can be unscrewed for cleaning but have to be rotated back to same position, and there are multiple thread connection points.

Image below shows the rangefinder couple ring partially unscrewed to expose thread for inspection. Grease looks clean there (since it's barely used lens) so I don't need to unscrew it completely.

I'm rotating that rangefinder couple ring back to marked position.

Then you can use spanner wrench to unscrew rear optical module. It opens access to the aperture chamber for cleaning blades and inner glass surfaces.

NOTE: Rear optical module can be unscrewed CCW using spanner wrench without disassembly steps listed above, this module can be easily extracted any time.

At this point I'm using Rocket Blower to get rid of minor dust particles in aperture chamber. Then I'm assembling lens back in reverse order of steps above.

One of most challenging part of assembly is to catch the focusing thread when core is mounted back with focusing knob right above "m" letter of distance scale. Once that is done focus lens to infinity until focusing knob is locked.

After that flip lens facing down, attach rangefinder couple ring and loosely screw in three black bolts. Focus lends to 0.7m distance, and only then tighten three bolts. 

Conclusions

Voigtlander 40mm F2.8 lens is very solidly built and is quite easy to perform CLA. Access to aperture chamber is relatively simple if you have experience using precise spanning wrench. I noticed signs of securing glue on bolts, so unscrewing them require initial high torque to loosen glue first. Due to very compact lens size this Voigtlander 40mm F2.8 Heliar requires higher accuracy of all moves and more patience comparing to working with averagely sized lens.

I was wondering if there is a way to extend the minimal focusing distance, but focusing thread movement is also limited by rangefinder couple cylinder, so it is not possible. Though minimal 0.7m distance is still close enough for most shooting scenarios.