Relubing a CZJ 35 2.4 instruction?

torbod · Joined: 31 Jan 2010 Posts: 379 Location: Sweden

I'd like to relubricate the focusing helicoid on a Flek 35 2.4 - Does anyone have a simple description for the disassembly? I have only found several instructions for fixing the aperture which is fine on my sample.

BR
/Tobbe

Spotmatic · Joined: 18 Aug 2008 Posts: 4045 Location: Netherlands

It's been a long time ago, but isn't the focusing helicoid accessible when you remove the mount part (after removing the 3 bigger screws on the mount)? Then clean the helicoid with cotton swabs and naphta (lighter fluid) and apply a little lubricant (I use lithium grease for that).

torbod · Joined: 31 Jan 2010 Posts: 379 Location: Sweden

sichko · Joined: 20 Jun 2008 Posts: 2475 Location: South West UK

1. Focus to infinity and make a note of the position of the optical assembly relative to the mount - how far does the rear element stick out from the mount ?

2. Remove the 3 screws on the back and lift off the back/mount - this shouldn't need any attention. If you have the electric version there are more than 3 screws (5 ?). Tricky ! But here are the ones to remove..
http://www.kolumbus.fi/uusilehto/img/lenses/zeiss/disass/

3. Keep the focus set at infinity - tape it if necessary.

4. Take a picture and/or make a sketch. When you reassemble the lens the bits on the inside should be in the same position relative to the bits on the outside.

5. You now need to remove two guide rods. Each is held by two screws. These are often held by varnish. If they have not been removed previously it might be worth treating each with a drop of WD40 (and waiting a few hours) before trying to unscrew them.

6. #5 is usefully carried out in two parts. Remove only one guide rod after removing the 2 screws holding it. Using the edge of a small screwdriver make a scratch on the inside of the guide channel so that it is level with the outer case/base. This is a reference mark when reassembling. The second set of screws + guide rod can now be removed.

7. Unscrew the optical assembly from the outer case so that it comes out from the front. Do so slowly, count the number of turns, and make a note of the positions of the two parts when they come apart. This is the start point for the reassembly.

8. You now have access to the main helicoids which can be cleaned and regreased.

9. However before #8 the main case/base are two parts held together by a pair of much finer helicoids and a stop screw. The grease here can become very gritty and it might be worth separating them and cleaning - instructions available if required.

This is one of the easier lenses to clean. The screws are not made of cheese and if you have a screwdriver of the right size you should not damage them.

torbod · Joined: 31 Jan 2010 Posts: 379 Location: Sweden

Super guide sichko, thanx a million.
I don't know yet if it is enough just to clean the normal helicoid.
I feel some small jerks when turning the focus ring only between the 0.4 and 1m markings on the scale. Perhaps I'm too picky, shall I shall live with it and spare a surgery? Is it likely to get worse? Any opinions on that?

keltzar · Joined: 22 Apr 2010 Posts: 70

[quote="torbod"]Super guide sichko, thanx a million.
I don't know yet if it is enough just to clean the normal helicoid.
I feel some small jerks when turning the focus ring only between the 0.4 and 1m markings on the scale. Perhaps I'm too picky, shall I shall live with it and spare a surgery? Is it likely to get worse? Any opinions on that?[/quote]

The grease has dried out.

I' re-lubed 2-3 Flek 35/2.4 years ago so this is from memory ... and I've since sold all of them. Before you try the rear access (?!) ... see if you can extend to min focus and twist off the front section . You may find you can see enough of the helicoid to be able to clean it and re-grease it just enough for your use without more "surgery".

That's the thing I SO prefer Pentax takumar lenses. They hardly give trouble even if old. Whereas the CZJ lenses seem to need work every few years.

I recall one in PB mount which I serviced when I received it, and had to service it again a year later when I sold it. Some oils had migrated from the helicoid onto the aperture blades.

torbod · Joined: 31 Jan 2010 Posts: 379 Location: Sweden