Operations carried out
Cameras and lenses
Leica M2 - 1962
Un Leica-tastrophe
Cellar humidity? Partial flooding? Forgotten in a bag?
Initially, this Leica arrived in the “Operating room” for a blocked shutter.
The bottom plate did show some traces of rust on the screws, but often, this is nothing to worry about.
The condition of the visible curtain suggested a mandatory renewal.
The disassembly revealed a lamentable state!!!
Lucky break
The rangefinder is the most sensitive, delicate, fragile point.
Luckily it was still clear and contrasted with a few very minimal rust spots.
The roller arm and the fixing screws were barely marked, only the top of the darkroom was really attacked.
Before any disassembly, it is necessary to unseize all the parts, let it act well and then gently disassemble each necessary part.
The unseizing agent and impurities were removed in a first ultrasonic bath of Isopropyl alcohol.
Then a second bath in new alcohol in order to completely clean the mechanisms.
Overall, a Leica M is made with metals that are not very sensitive to rust.
Those that are, when attacked, tend to spread this rust on the surface of the rest of the mechanisms.
Conversely, oxidation is more frequent.
The original flocking of the darkroom, weakened by humidity, was stripped in order to make a new, more resistant matte black paint.
A very sensitive part is the curtain brake which is often oxidized and no longer brakes correctly. This results in curtains incorrectly positioned at the end of the shutter and a louder noise.
The darkroom was stripped of the original flocking weakened by humidity and was repainted in matte black.
The two curtain supports were cleaned before renewing.
The self-timer and other parts were treated.
The essential anti-fog on the top of the lens mount is often degraded, it was replaced.
Arming and trigger working again
Changing the curtains
A page is entirely devoted to this subject on this site.
Leica M curtains
The first thing to do when removing the old curtains is to completely release the tensions.
Then, VERY IMPORTANT, mark the gluing marks for the ribbons of the first curtain. This allows you to find the original positioning later.
Keep in mind that it is on the large drum that the gluing of the ribbons of the first curtain and the second curtain must be very precise. The gluing on the two tension drums is less important, because they only ensure the tension, except for the perfect vertical parallelism of the ribbons of the second curtain and the first curtain.
First functional curtain (basic setting)
Second functional curtain (basic setting)
Progress of curtain settings
A page is dedicated to this subject on this site. Curtain tension
The “basic” tension allows the shutter to operate at a minimum.
It rarely allows to obtain curtain scrolling times (in milliseconds) that are acceptable for the exposure speeds to be correct, it is “a starting point” to make the final adjustments.
Using a Shutter Tester necessarily equipped with three measurement diodes, you can measure the settings exactly and refine them.
It should be kept in mind that:
1/ It is the similarity of the scrolling times of each curtain that determines the exposure speeds.
2/ The speeds engraved on the camera button are “standardized” and never correspond to the real speeds of a mechanical shutter.
3/ The photos allow you to compare the evolution of the settings, in order to obtain the best between the scrolling times of each curtain and the shutter speeds.
4/ Depending on the standard speed selected, the curtain scrolling times change, this is the impact of mechanical shutters, especially if they are old and have suffered, which is the case with this device.
5/ Similarly for shutter speeds, when adjusting, compromises must be made. However, these differences generally remain within the manufacturer’s tolerance and have no visible influence on the negatives.
Slow speeds
The slow speed block must be cleaned with an isopropyl alcohol bath, dried well and lubrication must be done only on the axle bearings, never on the pinions.
The adjustment is made by the eccentric screw on the top and must be done to obtain 1/8.
The slow speed mechanism, especially for the second, allows you to see if the second curtain is correctly positioned. Indeed, when the speed of one second is triggered, the mechanism gradually releases the second curtain until it is released and closed. During this time the curtain moves slowly to the edge of the exposure window. If this curtain is incorrectly positioned, the edge of the curtain exceeds the edge of the window and can create a vertical area of underexposure.
Partial reassembly
Fully functional final reassembly
LEICA the legendary brand
I disclaim any responsibility if you damage your toys!!! There are also professionals to do this job!