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07-27-2013, 12:43 PM   #1
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Easiest M42 auto only mod?

My dear wife bought me a "vintage" Yashica TL Electro X kit from an estate as a birthday present. The kit contains three M42 lenses but all of them are auto-only. I would like to convert them to manual mode. According to my forum searches I found that the two most popular conversion methods are:

1) Take apart the back of the lens and put a spacer inside that pushes the pin as if the aperture function is always actuated.
2) Glue the pin down.

I don't want to take anything apart because I'm afraid that I won't be able to put it back together correctly. Plus, some of the lenses don't have any screws holding the back. I would need to take apart a bathtub plug to unscrew big pieces apart.

I feel hesitant about gluing the pin down because I'm afraid that the glue will eventually fail and bits of it will chip off inside the lens/camera.

Are there any alternatives to disassembly and gluing?

07-27-2013, 12:51 PM   #2
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Wedge the pin, maybe something like a toothpick?
07-27-2013, 12:51 PM   #3
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I would super-glue ... I have done it several times without any problems ... J
07-27-2013, 01:44 PM   #4
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I glued my Yashica 50mm f1.9 and Fujica 55mm f1.8, no problems at all. There isn't a lot of force on the pin, so I doubt the glue will ever fail. Just used standard super glue and used a needle to hold the pin down until the glue had dried enough to hold it.

07-27-2013, 02:22 PM   #5
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A short section of a ball point pen refil does the trick


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