[eskerman]

I am not sure if this is the right forum to ask this question - but I might as well try

I have an old SMC Takumar that was fitted to Asahi Pentax bellows -- and unbeknown's to me there is a small pin that has engaged in the bellows and now I cannot remove the lens from it.. I understand this is a problem and hindsight is a wonderful thing

if I have to "sacrifice" the bellows - fine and I just can't find any other option to unscrew this lens .. and its a lovely lens and I have had some great results with it on my Fuji X

Any advice or guidence would be greatly appreciated

Greetings from Ireland

Paul

[Not a Number]

Which bellows is it? I'm not aware of any pins that would cause a problem on the M42 bellows. If you are using a non-Pentax M42 adapter on one of the K-mount bellows it could be a problem.

Either way you should be able to get at the rear of the lens through either by collapsing the bellows or with the Auto bellows detach the bellows from the front standard.

If it is a k-mount you should be able to release the spring clip on the adapter then remove the lens and adapter. After that you can depress the pin with a small screwdriver or something to remove the adapter.

If not, you can try fitting a thin feeler gauge between the lens and mount to depress the pin.

[K2 to K50]

I recently discovered on my "Pentax Auto-Bellows K set" Bellows from the late 1970's that I can unscrew the camera mount from the body of the bellows. Haven't checked if the same applies to the lens mount at the other end, but if so, that may make it easier to work with?

[dkpentax]

Send a picture of the lens and bellows and someone will probably know how to fix the problem

[eskerman]

The bellows is Asahi M42 see photo

I have the bellows closed but the lens wont unscrew.. its kinda loose but definitely something (small pin) preventing from unscrewing

Does anybody have a Takumar (SMC) 50mm macro lens that may show any pin... can possibly get a small feeler gauge in between the lens and the bellows but can't see what this might achieve

Thanks for any assistance or further advice

Paul

[eskerman]

See attached image that shows the pin

Paul

[Piotrek K]

Did you tried to unscrew with different positions of auto/man (A/M) switch on the lens?

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Last edited by Piotrek K; 07-19-2022 at 07:50 AM.

[Not a Number]

Ok, the only thing the auto/man release pin could be hanging up on would be the mount screw holes. Even though the pin should be on a different radius from these holes.

A feeler gauge would depress the pin and cover over the hole allowing the pin to pass over the hole.

[GUB]

Ok, the only thing the auto/man release pin could be hanging up on would be the mount screw holes. Even though the pin should be on a different radius from these holes.

Maybe there is a screw missing in the bellows mount leaving a hole. Looking at my asahi bellows the pin would line up with the inner edge of the hole. i would have thought it would have just ridden back out again though.

[Not a Number]

If the pin isn't depressed then the auto/manual switch will lock in the "auto" position. So in this case if the switch can be changed back and forth from auto to man then the problem must be elsewhere. Unless of course the switch is broken.

[GUB]

If the pin isn't depressed then the auto/manual switch will lock in the "auto" position. So in this case if the switch can be changed back and forth from auto to man then the problem must be elsewhere. Unless of course the switch is broken.

With both my S-M-C Macros the pin stays recessed even when the lens is off. And only one out of 5 of my S-M-C / SMC 55s is stuck down.
Any one else with a SMC Macro 50 able to check?
Maybe it was a nuisance as in here and disabled.

[GUB]

So I just took the mounting plate off my bellows and tested it on a SMC 55mm and it did jam just as described.
The advantage of taking the mount off was I could recess the pin manually from behind. Sorry but this describes your problem but doesn't solve it. I think a screw is missing in your bellows mount ring.

EDIT I think it was the screw hole at 7 0clock that caught the pin. Figuring the bellows is going to have to be destroyed but - Try inserting a fine screwdriver between the chrome bellows mount and it's black plate at this 7 0clock position and see if you can get any play. And slowly force your way around the mount and try and shear the other screws. The best case scenarion is you destroy your screws but can glue the mount back on. It is possible that it may not be the screw at 7 0clock missing - it is just that it is the last one the pin passes over.

[Not a Number]

On my Super-Multi-Coated Takumar 50mm f/4 macro the pin stays in when set to "man". If you switch it to "auto" the pin pops out and it locks in "auto" until you depress the pin. When set to "auto" the pin pops out when you release it after pressing it in (spring loaded).

[GUB]

On my Super-Multi-Coated Takumar 50mm f/4 macro the pin stays in when set to "man". If you switch it to "auto" the pin pops out and it locks in "auto" until you depress the pin. When set to "auto" the pin pops out when you release it after pressing it in (spring loaded).

Then my two have either stuck with age or someone has glued them.

Edit even though the pin isvery fine I suspect it will extend too far for a feeler gauge to get under it but here is hoping.
And I wonder if my ones are stuck because someone has forced them and bent them a bit. (It may be the way to go)

EDIT again. If the screw slot happens to be in the exact radial from the centre position then it could trap the pin just like a missing screw.

[GUB]

Post 2

https://www.pentaxforums.com/forums/8-film-slrs-compact-film-cameras/229285-...ty-issues.html