This lens is in very nice cosmetic condition, but had a lazy aperture and there was a gray things in the lens edge.
The lens itself was nicely built. Very high quality precision parts, and quite easy to service. Most of the Super / SMC / Super Multi Coated Takumar that I worked on have similar design. The steps outlined here could be used as a guide to other lenses in this family.
As for image quality, I can’t make any comment, since I never use these lenses ( I got 2 in minty conditions). The focal length is too close to 30mm, so I always use my K 30/2.8.
Remove the front name plate (A) with a friction tool. As usual I use the rear cap covered with heavy yellow rubber glove. In this copy the ring was stuck, so I dropped a few naphtha, put the front cap and let it sit for an hour.
There is another part under the front plate. It is attached by 3 screws. Remove these screws.
Underneath you will find 3 screws with brass washers. These screws connect the focusing ring with the outer helicoid. Remove these screws.
Remove the focusing ring. Also remove the DOF scale ring, it is hold together by 3 small headless screws. Now you could remove the aperture ring. Again, be careful of the ball bearing underneath.
With a spanner, remove the front lens group (A).
Now separate the aperture actuating assembly by removing the 3 screws on the barrel.
If you need to relube the helicoid or accessing the aperture blade, remove the 2 tabs (A) each held by 2 screws.
The lazy aperture was not caused by oil on the blade. It turned out that by loosening the 3 screws a little bit, the aperture was snappy again.
On reassembly, make sure the the position is right. The aperture actuating lever & hook (for I don’t know what to call the F shaped part) (B) and the notch and ball bearing spring (C) are in the same position.
If you need to access helicoids, just turn the brass ring until the the helicoids disengages. To access the aperture blade, you have to remove the O ring with a spanner.
After completely disassemble the lens, the gray thing turned out to be some flaking lens blackening paint.
Note on reassembly
Reassembly is quite straightforward, just reverse the process.
If you remove the helicoids, you need to adjust infinity focus :
A. Asemble the lens until you arrive at step 4. Mount the lens to a camera with known good focusing.
B. Focus the lens at a distant object. Now mount the focusing ring at infinity position. Attach only 1 screw, don’t tighten too much. Check the focus again, if it moved, loosen the screw and readjust.
C. Put the rest of the screws and tighten.
This lens has a similar construction with other Takumars, except for the internal filters. I have removed the UV internal filter since it contracted a bad case of haze.
Remove the name plate (A) with friction tool the usual way. Make sure the tool will not touch the bulging front element. My favourite tool, a Pentax rear lens cap & rubber glove (C) do this job nicely. Then remove the 3 screws holding the filter selector ring (B).
Once the filter selector ring (A) was removed, remove the 3 headless screws (B) holding the indicator ring. Remove the 3 focus screws & washer set (C), then remove the focusing ring.
Remove the 3 headless screws (A) holding the aperture indicator ring. Also remove the focus limiter screw (B). Then remove the aperture selector ring (C). As usual, beware of the booby trapped ball bearing.
Remove the 3 screws (A) holding the front and back part together.
To remove the front lens group, first remove the 2 tabs (A), and turn the front group. On reassembly, rotate the front lens group you could :
1. Align the cutout (B) with a piece of metal on the inner side of the back. The metal act as a spring for the aperture click ball
2. Insert the aperture lever (C – not visible) into the F shaped part of the aperture mechanism (C – not visible) bearing.
These are the parts after the front lens group was removed.
To access the internal filter, use a lens spanner to remove the front lens group from the helicoid. The internal filters are held in place by metal retainers.
To access the rear lens group elements, remove the filter holder (A), well a friend told me its some sort of filter holder, although I have no idea what kind of filter will fit into this. Next remove the rear cap (B).
Use lens spanner to remove these rings (A & B) if you need to access the rear elements.
Tips on reassembly :
A. Adjust the lens groups so it doesn’t press on the rear aperture assembly. Else the aperture might get sluggish or won’t move at all.
B. Focus adjustment. Put the front lens group to its minimum distance. Set the 3 focus adjustment screws, but do not tighten them yet. Turn the focus ring to infinity. If you don’t get infinity focus, loosen the focus adjustment screws and slide the focus ring around.
I used Andy Brown's tutorial as a guide. Andy recommended dunking the whole aperture assembly in soap water, I prefer to clean the individual blade. I would advice you to try Andy’s advice first, because this lens aperture assembly is more complicated than other lenses that I’ve worked on.
Optically this is a very good lens, but mechanically this lens is not on par with Takumars. There are some plastic parts inside, and it is not possible to fine tune the focusing mechanism. In my copy, it is possible to focus a bit past infinity.
For cleaning the blade, I prefer naphta, as some aperture blade corrode easily when exposed to water. For cleaning helicoid, I use water and laundry detergent.
Remove the 3 screws (A). Then just pull the back casing.
Remove the outer element and shroud (A). You could remove it later on, but I prefer to work with as little lens element as possible.
Remove the 4 screws holding the focus rod (B). Remove the rod right away.
Remove the focus adjustment screw (C)
Unscrew the end of the casing.
Pull the lens hood (A) and unscrew it. Some might have a small screw, mine doesn’t.
To remove the aperture assembly, unscrew the 3 screws and pull the assembly.
The A/M lever(C) is connected to a spring (B). Unhook the spring from the post (A). Then remove the A, C and D.
Unhook the aperture spring (D) first. I use a needle to do it.
Remove the outer collar (A), use a spanner for this. Then remove the inner collar (C)
Remove the aperture rod screws (B)
Remove the inner collar (C) . It is not screwed, you just need to pull it out. Installing it is a bit tricky, because the spring need to be attached first. I use a bit of gue to attach the spring, before installing the inner collar.
Installing the aperture blade is a bit tricky. Install all the items in picture 5.
Position the inner & outer disk so the lever is in this posotion.
Put the inner collar, it has a slot, so it will only goes in in this position. Make sure the outer disk is centered.
Attach the spring to the inner disk’s lever.
Pull the inner disk lever as far as possible to the right. Adjust the outer disk, so the aperture opening match the inner disk’s.
Remove the inner collar, and install the aperture rod.
Then install the inner & outer collar. You might want to install the aperture rod first,but I find it difficult to position the disks with the aperture rod & ring installed.