Porst Weitwinkel 35mm f/3.5 auto F M42 convert to manual

[carloM42]

Hi,
I have bought this lens. It is built nicely, all metal, and the focusing ring is one of the smoothest in my m42 lens collection. Since it is an an "auto" only lens I would like to convert it to manual in order to use it on my Pentax K-01 at all apertures. I have already converted a Mamiya Sekor sx 28mm 2.8 by fixing the pin with the ball point pen refill trick but I followed a great tutorial with photos . Instead this lens seems to me more difficult to disassembly and I really don't want to damage it because it is in very good condition. If someone can give me some guidance it would be great!
TIA!
Carlo


PS: sorry, I tried to upload a photo of the lens, but this is my first post and it seems that I cannot upload any photos!

[carloM42]

I try to add some images. I hope that someone can give me some hints. Maybe I just need to be brave enough to unscrew the small screws on the side. I'm just afraid of not being able to realign the lens (I already had a bad experience with a fujinon 55mm but It was socheap that I didn't care..).
Otherwise I am going to glue the pin

[Lloydy]

On a lens that I couldn't get apart I have also glued the pin down. But not with superglue that some people use. I used a contact cement that dries rubbery and can be peeled away. The problem is, it dries slowly. Clean the area around the pin with alcohol and let it dry. drip some contact cement on the pin and push it down with the point of a plastic toothpick, hold until the glue is dry and carefully remove the toothpick. Hopefully there is now a little mound of glue holding the pin down.
The lens I did this on has held for a long time now with no problems at all. Here's a picture taken to show the lens ( Fujinon 55 / 2.2 ) but you can just a small lump on the back face which is the mound of glue.

[carloM42]

Thank you Lloydy, I like your solution!
I didn't want to glue the pin down because I tought that it was not reversible. Now I realize that many different kind of glue exist.
Thank you!

[kansalliskala]

Don't unscrew the screws on the side of the lens if you don't know exactly what they are. Usually one ends up with a lens with moving parts you don't want to move.

I'd just buy another m42 adapter with flange for about $10.

[carloM42]

Hi kansalliskala, yes now I think that I will not try to disassembly the lens. I will also consider the adapter with flange: thank you for the suggestion!
I think that those old lenses are getting more and more rare and it's a pity to run the risk to damage them.