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Stiff focusing ring on a Biotar 58/2...? No problem!!!
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PostPosted: Sun Jan 17, 2010 11:01 am    Post subject: Stiff focusing ring on a Biotar 58/2...? No problem!!! Reply with quote

hi All

this is how i opened, cleaned and greased, oiled, my biotar 58/2...and put it back togheter

first step:

Before trying this the first thing to do is to check if you can unscrew the ring at the rear element, just loosen it and tighten it back, it will go off later, if you can`t unscrew it then i suggest that you DO NOT go on. I did maneged to put back the lens even without unscrewing it, but it took me four hours! It`s the outer, bigger ring, not the inner that holds a lens element!



Now if you can do that, we can go on, open up the aperture to f2 and align everything



unscrew the screw wich acts as a stopper, limiter



now you turn the FOCUSING ring twards close focus ClockWise, it can be very stiff, keep turning, at one point the upper, front, part of the lens will start to turn, keep turning, it will come out at one point, do everything very gently, never force at this point...



now you can turn the focusing ring all the way out, depending on the condition of the lens, this can be very, i mean very hard!, the focusing ring has a very fine thread, so when you turn it, it looks like it`s threadless...



now you can clean, grease, lubricate, the threads of the focusing ring, use your preferred method, but NEVER use generic sprays like WD40 for example, use one that it`s not acid!
now let`s go back to the front part of the lens, remember the ring we tested? it`s time to unscrew it, under it i found a spacer ring



once you removed them pull up gently the inner ring, it should come off easely, clean, grease, lubricate and so on everything you want...after that it`s time to put the lens together !!!

first, screw back the focusing ring, start to screw it in at infinity position



go all the way in, this is important, becouse otherwise you probably won`t be able to achieve infinity, depending on how you greased it, it may still require some force, my lens reaches the end at a position marked at around 0,65 m



unscrew the focusing ring back to reach infinity then add one more full turn, 360 degrees, if you don`t add this turn you want be able to turn the focusing ring enough in the opposite direction, when needed, simplly put, screw it to the closest infinity position at the end of the thread, then unscrew it one turn, it`s much more easy to do than to explain it



now comes the tricky part: take a look at this picture, no really take a long look, taken before the focusing ring is in position



the notch, jag, incision, however it`s called, on the inner ring of the lens, has to go into the tooth (translation pending), that is screwed on the inner part of the rear ring of the lens, on this picture the focusing ring is in it`s place



to do this put the inner ring into the focusing ring, align the notch to the tooth (TP), turn it ClockWise just a few milimeters, to find the beginning of the tread, once you achieved that, turn it CounterClockWise, you will have to hold the fousing ring in place all the time, move the notch exactly above the tooth, the goal now is to turn the focusing ring CounterClockWise (twards infinity), so that the notch slides onto the tooth, i do it by moving alternatevly the inner ring and the focusing ring, by just a milimeter or so, at one point when the notch reaches the tooth you won`t be abe to turn the inner ring, if you nailed the position you`ll be able to turn the focusing ring to reach infinity, a series of pics:


this is the starting position






by "playing" and with a lot of patience you should be able to do it, i opened and put togheter the lens now five times, it takes me a few moments to do this and 10 minutes to do all the work, i`am by no means an expert, it`s the first lens i opened, the end result:



the rest is much easyer, put back the spacer ring, as a side note for nikon users, i tryed to put the lens togheter without it, but you still can`t reach infinity without a glass adapter



now align the two red triangular marks, be careful, the spacer ring is easy to move



the rear part should just drop onto the front part, now screw on the retaining ring at the back of the lens



oh and dont`t forget to put the limiter screw back in!!!



that`s it!!!

Disclaimer:
1. try this at your own risk
2. your biotar 58/2 can be different
3. befor doing it, wait to see if this post will have some interest, so we can discuss the process and maybe i˙ll have to answer some questions
4. to the administrators: feel free to move or remove the topic, if you think is too "dangerous"
5. please feel free to correct all the grammatical errors, and find a translation for the "tooth" Very Happy

tomas


Last edited by tomasg on Tue Jan 19, 2010 5:28 am; edited 6 times in total


PostPosted: Sun Jan 17, 2010 11:51 am    Post subject: Reply with quote

Congratulations ! Very helpful, precise tutorial ... ! I have a Biotar on the way to CLA, but I only "contemplate" it ... and unscrewed nothing for one year ... Many thanks ! Very Happy


PostPosted: Sun Jan 17, 2010 3:41 pm    Post subject: Reply with quote

Tomas,
Thanks for sharing.
Mike


PostPosted: Sun Jan 17, 2010 4:10 pm    Post subject: Reply with quote

Thanks a lot for sharing!
Putting back together this lens can be very frustrating. Wink


PostPosted: Sun Jan 17, 2010 4:34 pm    Post subject: Reply with quote

Thanks for sharing! Good habit to take photo for each step! Seems like there will always be some extra and useless parts when we resemble something, at least I am Very Happy


PostPosted: Sun Jan 17, 2010 5:07 pm    Post subject: Reply with quote

I managed to get mine apart & back together, but it did cause some problems at first. I did it differently to this though. I just removed the screw and it came apart. I have a technique of putting it together which requires 3 hands but it works.


PostPosted: Sun Jan 17, 2010 5:27 pm    Post subject: Reply with quote

Quote:
I have a technique of putting it together which requires 3 hands but it works.


yes, this is the way i did it first...but after an hour or so my GF`s third hand run out of patience Very Happy


PostPosted: Sun Jan 17, 2010 7:45 pm    Post subject: Reply with quote

If you find a way or know of a way to adjust the infinity focus I'd be interested. Mine doesn't seem to hit infinity on my Chinon. Most lenses are ok, but this one and another cause issues only on that camera.


PostPosted: Sun Jan 17, 2010 9:58 pm    Post subject: Reply with quote

Great work Tomas. Is that Torx screw original??

I'd like to move this thread into the Equipment Care section, do you have any objections?


PostPosted: Sun Jan 17, 2010 10:48 pm    Post subject: Reply with quote

Many thanks to sharing!


PostPosted: Mon Jan 18, 2010 5:30 am    Post subject: Reply with quote

Quote:
Is that Torx screw original??

I'd like to move this thread into the Equipment Care section, do you have any objections?


no, the torx is not an original, the lens as is doesn`t reach infinity even with an adapter with lens, on my Nikon d200, so i keept the limiter unscrewed a bit, this allows the focus ring to go past infinity thus allowing to get a focus...this is how i lost the original, i`am still looking for a better replacment, it`s a specific screw hard to find

no problem, move it as you wish

tomas


Last edited by tomasg on Mon Jan 18, 2010 4:21 pm; edited 1 time in total


PostPosted: Mon Jan 18, 2010 7:12 am    Post subject: Reply with quote

THX for sharing..

Cheers
Henry


PostPosted: Mon Jan 18, 2010 8:25 pm    Post subject: Reply with quote

Hi,

I was just looking for this ... Hopefully i can fix my Biotars now Very Happy ...

Many thanks for sharing!

Cheers


PostPosted: Tue Jan 19, 2010 4:22 pm    Post subject: Reply with quote

Quote:
If you find a way or know of a way to adjust the infinity focus I'd be interested. Mine doesn't seem to hit infinity on my Chinon. Most lenses are ok, but this one and another cause issues only on that camera.


try to unscrew the limiter screw, this will allow the focusing ring to past the infinity mark, this way the rear element goes closer to the focal plane, if you get infinty focus this way then i guess that the focusing ring is off a bit, i don`t know your camera, be careful not to over do it, so that the mirror hits the rear element...

tomas


PostPosted: Tue Sep 09, 2014 2:27 am    Post subject: grease? Reply with quote

You really make this seem doable. I have never taken apart a lens - what did you use to lubricate the parts? where does the lubricant get applied?

Thanks


PostPosted: Wed Mar 29, 2017 1:09 pm    Post subject: Thank you Reply with quote

As a new member I've not yet checked to see if tomasg is still active on the board, but I'm posting to say thank you.

This biotar lens comes apart so easily your logic is defied when you find it's not so straightforward to reassemble it. So you continue to try to put it together as a reverse of how it came apart. Over and over again! I've read that doing the same thing over and over again expecting a different result can be a sign of madness. I may have been getting close. For a couple of months now I've randomly picked up the lens, tried to mate the two parts, *sighed*, then put it back on the shelf. Then I came across your post. 15 minutes later the lens is back on my camera (a Pentax SV). I have the feeling I can't be alone in reading your post and a lightbulb suddenly turning on. As I said earlier, the ease at which the lens comes apart seems to block your mind to reassembly being anything other than a reverse of the same.

If I can help a bit in return. On reassembly I found the same problem of not being able to reach infinity. After some thought I introduced the focusing ring to the depth of field marked ring at 2.5m rather than infinity as you suggested in your original post. This has allowed infinity to be achieved, but at the expense of the distance scale being slightly out. Infinity is being reached just before infinity as indicated on the lens barrel. But at least I now have infinity. When I have more time I'll be going back to do some more trial and error on where the best position is to introduce the focusing ring to the depth of field ring.

Thanks again.

Up and running -

[img][/img]


Last edited by Sciolist on Wed Mar 29, 2017 2:46 pm; edited 1 time in total


PostPosted: Wed Mar 29, 2017 2:20 pm    Post subject: Re: grease? Reply with quote

qvillin wrote:
You really make this seem doable. I have never taken apart a lens - what did you use to lubricate the parts? where does the lubricant get applied?

Thanks


For the various threads I used a simple general purpose grease. I don't know if that is correct or not. Time will tell. I used the smallest amount I could get away with - just enough to give the threads a 'wet' look in reality. You couldn't actually see any grease if that makes sense, just the sheen. The focusing is now very smooth and with just the right amount of resistance (for my taste anyway).

I did actually experiment with giving the threads a wipe with watchmakers oil first, just to see how it felt. It produced zero resistance (damping) when focusing, although the focus did not move once set. But I didn't like the feel, and also had visions of the oil, as sparsely as I had applied it, eventually finding it's way to places it shouldn't go. So I wiped it off and applied the grease.

With regard to the other mechanisms - the aperture selection and pre-set function for example, my advice (as an amatuer at this) would be to leave it alone if it is functioning correctly. And if it is sticky, try lightly and gently cleaning before thinking of doing anything else. I always have in my mind that oil/grease and fine mechanisms are not perfect bedfellows. For mechanisms in the camera itself for example, I go no further than a drop of watchmakers oil being pulled off the end of a sewing needle (capillary action? - just load the pin with a drop of oil and touch where you want the oil to go) And even then I'll still find myself wiping off the excess.

These things can be trial and error, but always start with what you think may be too little. You may find, surprisingly, that it's sufficient.


PostPosted: Thu Mar 30, 2017 6:55 am    Post subject: Reply with quote

Still alive and kicking, although i mostly only read posts here now. Soon i ll have my tutorials posted on another site with which i am starting a collaboration, i ll post the links here.
Regarding the infinity on my Biotar i found out that the cause must be the fact that i used the front part of the optical block from another lens, so mine is a kind of a hybrid. If i put the whole optical block of a Tessar lens with its original shim it reaches infinity with the Biotars "body". The two lenses are clones mechanically. Viceversa if i put the Biotars block into the Tessar body infinity is lost.
A small tip for greasing, i find most of the greases to stiff to be applied in a correct amount, since the are difficult to sprad on the threads we put more of it, resulting in a stiff focusing. I add few deops of oil to the grease in a small pot, mix it and applay it to the threads. This way i put the correct small amount of grease and since it s softer it s easy to spread it with a brush and grease all the thread. At first the focusing is a bit on a soft side, but as the solvent in the oil evaporates it gets stiffer, after a couple of weeks/months. I use 1 or 2 drops max, so i wouldn t over obsess about the residue depositing on the lens surfaces, but even if that s the case it s easy to clean them.

Tomas


PostPosted: Thu Mar 30, 2017 8:56 am    Post subject: Reply with quote

tomasg wrote:
... A small tip for greasing, i find most of the greases to stiff to be applied in a correct amount, since the are difficult to sprad on the threads we put more of it, resulting in a stiff focusing. I add few deops of oil to the grease in a small pot, mix it and applay it to the threads. ...

Tomas


I first coated the threads with oil to see what it was like. Then I wiped and applied grease. I know that there would still have been some oil in the grooves before I applied the grease as I only gave it a 'surface' wipe. As I too ended up with a really nice focusing action it seems that it's a good combination.

Do you follow a similar regime on other lenses Tomas?


PostPosted: Fri Mar 31, 2017 6:40 am    Post subject: Reply with quote

Yes, on almost all lenses i grease them with a diluted grease, though i prepare fresh grease every time, really the amount of grease is smal plus a drop of oil, it can be done even on a piece of paper or wood, almost like a painter does it. Smile
More problematic than the threads are the parts that are rotational and need to be assembled tightly togheterd, for example some Russian lenses like the Helios 44-2, Tair 11, the rear part of the focusing mechanism is more difficult to grease to get the right amount of resistance. Them there are big and heavy lenses, like Helios 40 for example, due to the weight of the front of the lens it s difficult to struck the balance between a not too stiff focusing and no "grinding" while one turns the focus ring in a horizontal position for example. Very fine threads also need small amount of not too sticky grease and so on...

Tomas


PostPosted: Fri Mar 31, 2017 7:58 am    Post subject: Reply with quote

Thanks Tomas.