1939 Summitar collapsing into Leica M cameras...

[dufffader]

So, I got a grime covered uncoated Summitar from the bargain bin a while back. The aperture stop was stuck (old grease?), and there were garbage inside the lens itself, what looked like excessive dust and metal shavings. Looked like a disaster. However, got it refurbished at Focal Point and I must say John did a great job with it. Now it looks like it's ready to rock.

Tested it out for the first time this weekend on an M3. Used the standard Leitz LTM-M adapter. I was expecting this lens to collapse cleanly into the M3, but to my surprise it seems to hit the focusing cam on the M3. Only with a little wiggling, will it collapse. And once it does, it extends cleanly without hitting the cam. I tried it on my M6 and M2 and it was the same.

Is this a known issue? Or specific to my case? Guessing it has to do with the adapter and the fact that the lens is not dead center when used with an adapter.

 

[Nikon Bob]

I am thinking this is not a known issue. Both my post war Summitars collapse properly into both my M4 and M4-P. That is using a non Leitz adapter. Wish I could be of more help in diagnosing your specific problem. Have you tried using a different adapter to try and eliminate the adapter as the cause of the problem?

Bob

 

[hans voralberg]

Strange, I've only used VC and cheap chinese adapters but never had this problem, I used my Summitar on my M3, M6 and M8. Why dont you check the rear end of the lens, the locking base of the collapsing barrel.

 

[dufffader]

Strange, I've only used VC and cheap chinese adapters but never had this problem, I used my Summitar on my M3, M6 and M8. Why dont you check the rear end of the lens, the locking base of the collapsing barrel.

It looks like one of the flange that protrudes from the barrel by about 1mm scraps the focus cam ever so slightly. I'll just keep it extended just to be sure I don't screw up the focus calibration by banging the cam with the rear end all the time.

 

[planetjoe]

I've only used Summitars (two different vintages, mid-50s) on an M4, but I've never had issues with internal contact. I'm just guessing, but three things come readily to mind, listed in order of decreasing likelihood:

1. The Summi locking cam (at the rear of the optics barrel) has been tweaked out-of-place radially, leaving it further from the barrel wall. This might allow it to reach the cam. Radial position isn't really crucial; it should normally be quite tight.

2. The RF follower arm (that carries the cam) is out-of-whack, bent ever so slightly downward into the shutter crate. This is certainly a more radical suggestion, as I'm not even certain the arm can bend this way and still function.

3. The RF cam itself is sitting proud (i.e., too high) from its location at the end of the RF follower arm, perhaps due to a shim, debris, or reassembly error. Note that by being "too high", the cam would actually project downward too far, also fouling the lens.

Just idle thinking; good luck with your investigation.


Cheers,
--joe.

 

[dufffader]

Hi Planetjoe,

I dont think its the cam on the camera itself as I've tried it with two other Leica Ms and it was the same. So the issue is probably something to do with issue 1 you mentioned. I'll need to study this further.

There are 3 flanges that fans out of the barrel and whose job is to lock the barrel tight when extended and turned to the right, and I'm guessing that normally these flanges are located a few radial degrees (radial turns) away from the cam, so it doesn't touch the cam when collapsing. If I make any sense at all... On my summitar it seems to be out of alignment, perhaps due to the adapter, thus hitting the cam. But its an original Leitz adapter so it doesn't make any sense.

 

[Nikon Bob]

I just had a look at my Summitar with the LTM adapter on. With the lens fully extended but rotated to the unlocked position and then pushed rearward none of the three locking lugs on the Summitar should be anywhere near the focusing cam of the camera. If you are looking from the front of the lens the locking lugs, when retracting the lens, should be at the 11 o'clock, 2 o'clock and 7 o'clock positions. Did you try the lens on your camera before having it fixed and you did not have any trouble collapsing it? Maybe ask Focal point about your issue and the possibility that your lens may have a reassembly problem with the locking lugs not being in the proper position.

Bob

 

[dufffader]

I just had a look at my Summitar with the LTM adapter on. With the lens fully extended but rotated to the unlocked position and then pushed rearward none of the three locking lugs on the Summitar should be anywhere near the focusing cam of the camera. If you are looking from the front of the lens the locking lugs, when retracting the lens, should be at the 11 o'clock, 2 o'clock and 7 o'clock positions. Did you try the lens on your camera before having it fixed and you did not have any trouble collapsing it? Maybe ask Focal point about your issue and the possibility that your lens may have a reassembly problem with the locking lugs not being in the proper position.

Bob

That's where the problem lies. I tried mine on and one of the lugs is on the 12 oclock position.

No I didn't try it on before I sent it for CLA, so it could have been the issue before I sent it to CO. Thanks for the tips, at least I know what to say when I send it next for the "adjustment".

Thanks Bob!