relubing a Hexanon 28

[sanmich]

Hi all

I am now the new proud owner of a Hexanon 28.
The lens is spectacularly well built.
Only one thing disturbs me: the focusing is stiff. And, well, that was one of the reasons I wanted to "upgrade" from my Ultron.:bang:

Does anyone around here know how to safely open the double helicoid and relube the beast?
(I have some experience in opening Canon RF lenses, but they are very simple to work on)

Thanks🙂

 

[pfoto]

Surprised to hear it is "stiff". It shouldn't need relubing. The 28 is heavily damped so it does take more effort to turn the focus ring in comparison to the Leica 28, yes. Does it feel smooth through the rotation of the focus ring?

 

[sanmich]

It is very smooth and the quality feeling is inferior to nothing I know. I don't think something is really wrong, although it could be that it has been relubed with a grease that is too thick.
Heavily damped it may be, but I feel I much prefer the free and effortless motion of the leica lenses. I was just thinking that a relube with a lighter grease should improve this.

 

[awilder]

Send it out to a reliable tech to have it done. DIY can be a little risky as Konica tended to overdo the application of glue to secure certain internal parts.

 

[Dante_Stella]

Your best bet is DAG, who will probably tell you in no uncertain terms not do to it. Hexanons are stiff in general; it seems to be a combination of tight machining and lubrication. But all lenses will loosen up over time. I would leave it.

 

[sanmich]

Thanks for your answers folks

I did talk to Don yesterday.
He told me that changing the lubricant to a lighter one is definitely possible.
The grease that I see on the lens seems to be a quite heavy, white grease, while on the leicas, it seems to be much thinner and transparent (you can't see aglomeration of grease at the end of the helicoids).
Under Don's advice, what I did meanwhile was to add a few drops of oil to lighten up the grease. I works so far and the movement is easier so far.

Dante, I wander why you think the best thing to do would have been to leave the lens that way?
Do you know if specific design+machining options require specific lube thickness? or can we adjust any lens within a certain range of stifness by changing the grease?

Also, mechanically, what makes a stiff focusing lens getting lighter with time? Is the lubricant changing it's proprties?

 

[tomasis]

I also curious about the hexanon though it is 90mm. It is STIFF as hell. my fingers always slip when I want make fast focusing from infinity to close distance. Though focus movement is consistent, smooth, heavy damped.

I think at general Konica quality is not up Leica terms. Aperture thing is a bit lose and focus grip is very tiny, too flat and slippery to make enough force to do movements inside two barells. That overcomplicated thing is the problem which seems tough to deal. I have same problem with Jupiter 85/2. Same two inside barells. Even it is poorly made design, I like optics 🙂

I think maybe I'd leave the lens for a while and see if it gets easier some time later.

Dante, how it turned out with your 90hex? focus became easier?

 

[infrequent]

I think at general Konica quality is not up Leica terms.

Neither is the price.

 

[Bobfrance]

Was the lens shipped to you by air?

I only ask as I recently bought a ZM 50mm from a guy in the states, which was stiff when it arrived. The seller promised me it wasn't when he sent it (the lens was only 18 months old after all). After discussing it with a former RFF member, who has had more lenses apart than I've had hot dinners, he said it could well be sympoms of the grease reacting to being kept at low temperature in an unpressurized hold. His advice was to try gently warming it (under a desk lamp for instance) and working the focus back and forth. Also just use it.
After some use it is now becoming looser and smoother.

Interestingly. I sold a 50mm Colour Skopar to someone in Italy. Upon it's arrival he commented that the focus was stiff. This surprised me as it was a well-used, but looked after, lens and nice and free in operation when I sent it out.

I wonder, has anybody else had experience of lenses stiffening up when shipped by air?

 

[sanmich]

Tomasis

I think any lens can be very stiff with the "right" grease.
I find the built of the Hexanon excellent, better than VC and maybe of my ZM Planar.
If you like the optics but think like me that the focus is too stiff, you can send it to DAG, simply to have it relube with lighter grease (That's what I plan to do if I I don't get used to it)

Bob, that's a very interesting point. I never thought about it but it perfectly makes sense.
My lens is already feeling better, wether it is from the oil addition or me playing with it or the grease warming up. I don't know...

 

[tomasis]

sanmich, I agree. Hex is second best after leica 🙂 Too bad Konica just discontinued. I have thought about sending the lens to Dag since I owned half year ago 😛 But I will wait until I get other 90/2.8 for comparisons. I'm interested of results when you get the lens back from DAG.

 

[tomasis]

Neither is the price.

Well that was great. But no availability. Who know if prices of konica lenses get up due collector values 🙂 Look at 50/1.2.

 

[infrequent]

@tomasis - that would be nice, wouldn't it?! even the normal one is rarer than any leica lens.

 

[amateriat]

I have three M-Hexanons (28, 50 and 90). They're all fairly well-damped (compared to a number of Leica lenses I've used), but not overly so IMO. And I don't find the focusing or aperture rings noticeably "loose" compared with Wetzlar/Solms' best. I somehow doubt, short of some kind of physical abuse, that there's anything wrong with that 28, so I'm with Dante here: if it ain't broke, don't fix it.


- Barrett

 

[Dante_Stella]

My lenses are all still pretty stiff (although I just acquired the 28 two years ago - I bought the last new one Dr. Yao had). My 50 is the stiffest, and I've had it since late 1999/early 2000. Stiff(er) is completely cool if the lens has no focusing tab.

Grease always breaks down, and if decades of history teach us anything, it will always end up on the aperture blades. Stiff or not, annoying or not, I would rather forestall that day.

Also, relubing a lens is not a trivial operation. Lots of disassembly.

Dante

I also curious about the hexanon though it is 90mm. It is STIFF as hell. my fingers always slip when I want make fast focusing from infinity to close distance. Though focus movement is consistent, smooth, heavy damped.

I think at general Konica quality is not up Leica terms. Aperture thing is a bit lose and focus grip is very tiny, too flat and slippery to make enough force to do movements inside two barells. That overcomplicated thing is the problem which seems tough to deal. I have same problem with Jupiter 85/2. Same two inside barells. Even it is poorly made design, I like optics 🙂

I think maybe I'd leave the lens for a while and see if it gets easier some time later.

Dante, how it turned out with your 90hex? focus became easier?

 

[Krosya]

I really wonder what you guys mean by stiff focus. I have several Hexanons and none of them I'd consider stiff. For me they are just right. I have used Leica and CV and Zeiss ZM and Canon and Nikkor and FSU - Hexanons are the smoothest ones of them all. FSU usually stiffest ones. Newer Leica didnt seem all that smooth to me. Best one was Summicron Rigid. But for my taste Hexanons beat them all - all feel just right - 28mm, 35 UC, 50/2 and 90mm. And as well made as they are - I wonder (as was posted before) if there was some damage to the lens if your Hexanon is that stiff.

 

[tomasis]

Korsya, I bought the lens in the same country as I live there. Which Leitz lenses did you tried? My 50 cron 50mm 1979 and Elmar 2.8 older beat Hex easily when you want easy focus from inf. to close dist. Though both are CLA'd recently. So other lenses as 35lux preasph and SuperAngulon 3.4 has about same stiff focus as Hex90 but hey those leitz has tab so it makes it easy to focus. I wouldn't complain if I manage find a way to make custom acessory for hex to make focus easy but at the time I know that some people wouldn't like to have "too loose" lens 🙂 I just wish a Summarit with Ernostar optics. it has a lot of plenty grip, seems so. I'm afraid that if I buy Summarit, so Hex will collect dust in the shelf.

I believe all that is due design. Leica has done lenses in about a human lifetime and I can see fruits of it clearly 🙂 IT is not bad to make such produts at first time for Konica btw 😛

 

[Krosya]

Korsya, I bought the lens in the same country as I live there. Which Leitz lenses did you tried?

I had several 50 Summicrons - from rigid to current. Plus some other older ones - summitar, elmar and Summarit (old) 50s.
As far as 90mm - I had Leica Elmar and Fat TE 90/2.8 and Hexanons I have are smoother than all of them, just Rigid cron was as good.

 

[tomasis]

I had several 50 Summicrons - from rigid to current. Plus some other older ones - summitar, elmar and Summarit (old) 50s.
As far as 90mm - I had Leica Elmar and Fat TE 90/2.8 and Hexanons I have are smoother than all of them, just Rigid cron was as good.

Smoothness, hmm. IT probably explains tightening mechanics.

How about force to turn the whole round? When you do at instant fast way so it has to be easy not heavy. It is my concern.

 

[sanmich]

Also, relubing a lens is not a trivial operation. Lots of disassembly.

Dante

Well, it realy depends on the lens.
Some are a PITA, others are very easy; Canon lenses for example...
Also 50s are single helicoids which simplifies things.