Tuesday, March 19, 2013

Dis-assembly of a Minolta MD 50mm [new] f/1.4

Since I live in a rather far off place from the metro (urban traffic makes a 1 hour travel go up to 3 times as long) I'm usually saddled with issues of things I can (usually) only get in Manila or its neighboring cities. From my e-cigarette mods to my photographic stuff, most of them can be easily accessed in the greater Manila area.

Given that situation, my lens has developed a severe case of dust incursion, and possibly some mold/fungus, and Hidalgo is traditionally the best place to have them cleaned. Unfortunately, it's relatively far and my trips there are pretty infrequent. But on the other hand, it's just a manual lens and a prime at that, making cleaning it a lot easier than the modern autofocus lenses normally used in digital camera's. At least to my mind it was.

Here's a short guide on how I disassembled my lens.

Minolta MD ring (with the brand name, lens name etc) unscrews counter-clockwise, normally you'd need some kind of circular rubber to grip and rotate the ring, I did it with my fingers. It wasn't too hard.
There are two [filter assembly locking] screws (opposite each other) for the filter ring barrel. I used a 1.2 m/m flat head screw driver to unscrew them (counter-clockwise) the screws are pretty tiny, do not lose them!
Once the two locking screws are removed, rotate the focus ring to the nearest focus (or basically make the focusing barrel extend) to make it easier for you to grip the filter ring assembly and unscrew it from the lens barrel in a counter-clockwise motion, if it feels a bit stuck, try to rotate it clockwise and counter clockwise to loosen it.
Removing the filter ring assembly will reveal the 1st element assembly and it's secured into place with 3 screws. I used a 2.0 m/m screwdriver (+) and its loosed counter-clockwise. Though not as small as the filter ring assembly screw, they are still easy to lose so be careful.
Make sure you have a soft and clean area for when removing the 1st element (am using a microfiber cloth) so you can place it on it with ease and confidence. You can lift the 1st element assembly by hand easily, its not stuck by glue or any screws. However it is of a sealed element type, you can't really separate the bottom lens and the front element.
The mount block is secured by 4 screws in a butterfly position so you wont be able to misalign it when you screw it on. I used the same 2.0 m/m screwdriver for the filter screw assembly, the screws look the same but I'd keep them separate from the others as a precaution.
The mount block has an aperture lever (A) and the body/iris assembly lever (B), take note of this when re-assembling the rear mount block as they have to be in the correct position to work properly. The rear element is removable by hand, just unscrew in a counter-clockwise manner. 
If you look hard enough you'll see a retaining ring over and around the rear element glass. There is a way to separate the rear element glass from each other, unfortunately I do not have that tool at the moment to unscrew it.

For now, this is as far as I go, since my purpose here is cleaning the glass, this should be enough. If you find fungus or dirt inside those sealed elements, then I'd have to say either tough luck, or better start finding that retaining ring wrench/pliers for unscrewing the rear element tube. the front is a lost cause unless you want to force it but you'd probably have a hard time putting it back together.

I'll try to add more guides on how I cleaned it and what I used tomorrow. for now it's zzzzz time.