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Tele-Takumar 200/5.6 Preset Disassembly
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PostPosted: Sat Jun 16, 2012 6:46 am    Post subject: Tele-Takumar 200/5.6 Preset Disassembly Reply with quote

I was wondering if anyone had ever disassembled this lens.

The lens has a preset aperture in the front part of the lens and it appears to be between the 2nd and third elements. I noticed that the lens has fungus on what appears to be the element directly behind the aperture blades. On most presets that I have in the 100mm+ range the barrels can be twisted apart and the lens groups come out which makes cleaning the interior elements fairly easy, this does not appear to be the case with this lens though.

On this lens I have removed the front name ring, the retaining ring below that as well as the first lens element, but it doesn't appear that I can get any further. I have not yet tried tackling this from the rear of the lens, any ideas?

Steve


PostPosted: Sat Jun 16, 2012 10:51 am    Post subject: Reply with quote

Post a picture from stage where did you stop and can't go forward , may somebody help if see it.


PostPosted: Sun Jun 17, 2012 1:20 am    Post subject: Reply with quote

Here are some pictures of the lens:
This is the exterior of the lens, there are no visible screws anywhere on the outside. There are no screws hidden when you change the focus range either. I have several older lenses in this focal range and on many of them the barrel twists apart to expose the elements, I have not had success doing that with this lens.

This is the rear of the lens, I have not yet attempted to remove the back, the first rear element is set fairly deep into the lens.

This is the front of the lens with the name ring, there appear to be two elements in front of the aperture blades and a third just behind them.

This is the fungus which appears on what looks like the third element, just behind the aperture blades.

With the nameplate removed there is a retaining ring just in front of the first element.

After removing the retaining ring with my spanners the first element just drops out of the lens. The second element is set back a bit and does not seem to move, and I do not see any more rings that I can remove from this end.

Perhaps the barrel does twist apart or maybe there is a way to disassemble the lens from the back, I'm not sure
Steve


PostPosted: Sat Jul 07, 2012 1:44 am    Post subject: Reply with quote

I have the Takumar 200mm f3.5.
Gripping the two preset rings in one hand and the front barrel/filter ring in the other, it unscrews from the front of the preset rings. This lens module is on a long fine thread and the rearmost element protrudes back close to the diaphragm. There is then just the diaphragm and a long blackened tunnel back to the rear element which I think is accesssed from the rear.

My glass is OK but I have a loose/wobbly rear barrel section (includes the m42 mount) which I cannot figure out how to get at. The movement is between the DOF scale ring and the rearmost barrel/mount segemnt (just behind the rear silver ring).
Ideas ???
Regards and good luck,
Tony


PostPosted: Sat Jul 07, 2012 7:06 am    Post subject: Reply with quote

Tony,

Most of the preset lenses that I have come apart very easily just like you described, but for some reason the 200/5.6 did not untwist like that. I was finally able to disassemble the lens by coming in from the back. Once I removed the rear retaining ring and helicoid guides the whole barrel twisted apart and I ended up with the focus ring/rear assembly in one hand and the lens element in the other.

I also have a copy of the 200/3.5 I have never taken mine apart, but my GUESS would be that you might have loose helicoid guides. On most Takumars they are one or two small flat brass plates or (as in the case of the 200/5.6 above) small L-shaped brass plates that fit into slots on either side of the focus helicod, once you remove those plates the focus helicoid can be twisted off of the lens. If those plates are loose the focus assembly and rear of the end will tend to wobble. On the 200/5.6 above, once I removed the rear retaining plate (the one with the two little holes in it) I had access to the helicoid guides which were each held on with two small screws.

In looking at the mount end of my copy of the 200/3.5 my GUESS would be that the outer most retaining ring (the one recessed the furthest in with the two large spanner slots) would be the one that would give you access to the guides, but I don't know as I've never taken this one apart. It is entirely possible that you may be able to access these from the front of the lens. Since it's easy to do, take the front of your lens off again and look inside to see if you see the plates. If you can somehow gain access to the helicoid guides tightening them should fix your wobble. One word of caution, if you do get to the guides, and you decide to take them out for some reason, keep track of which one goes on which side. While they look very similar, I have encountered lenses where the two guides are slightly different and only fit properly in one slot or the other.

Sorry I couldn't be more specific on your particular lens, if I decide to take mine apart I'll give you an update. While many people don't seem to like this lens, I find that my copy is very sharp and actually one of my favorites.

Goood luck,
Steve


PostPosted: Sat Jul 07, 2012 6:26 pm    Post subject: Reply with quote

Welcome Tony/zorgvater!