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02-13-2020, 07:47 AM - 3 Likes   #46
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Not really dead, and not 100% saved but here goes:




Dirty.




Fungus.

Everything else is smooth as you like, focus is buttery and aperture is smooth and precise, both to set and during functioning.

Disassembled everything. Nitrile glove and the supplied base cap took reasonable care of the name ring. Three screws underneath for the name ring's collar.


Three screws underneath for the element assembly block. I marked one of the screw holes with a minuscule line to ensure it was being returned in the correct orientation, though I doubt that matters a huge amount given this couldn't be done for every element removed. Careful! There are little washers with these screws. They are minute, and look very easy to misplace!


'Labelled' the area initially with the tweezers but quickly replaced that for an unused toothpick.


Various aspects of the elements removed, usually with use of a lens spanner to remove retaining rings. Thereafter cleaned up with 6% hydrogen peroxide, isopropanol then naphtha, finishing with a small, clean microfibre. Nastiest chunk of fungus in the element block below!




Thereafter it was reassemble. The frontmost element is marred slightly by the fungus that was there. No mycelium left though! However, not a dust free environment by any stretch of the imagination, nor did I have my rocket blower handy (silly me). Ergo, it is now dustier inside than it was. I will address this in due course but the idea for today was to sort out the fungus, after receipt today. Considerably cleaner than it was and not bad for £10 + P&P! Looking forward to trying it out!



Note: Someone had clearly looked to take apart the front at some point during this lens' life. Note the mark under the 'A' of Pentax?

02-14-2020, 12:41 PM - 1 Like   #47
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I have the same lens to clean !

It is interesting to see it is not very complicated.
02-15-2020, 01:28 AM   #48
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QuoteOriginally posted by Praktica*ist Quote
I have the same lens to clean !

It is interesting to see it is not very complicated.
It certainly is a simple one! love the resulting pictures from it, too.
02-15-2020, 05:01 AM - 1 Like   #49
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QuoteOriginally posted by Benz3ne Quote
A couple I've done over the last few weeks. My first, second and third foray into disassembly and cleaning (but much practice still needed)! Unfortunately no pictures but happy with the results in each case.

SMC-M 50mm f/1.7. Received with some fungus on the rear element. Simple to disassemble, cleaned up with methanol then naphtha and reassembled. Clean as a whistle now, less a little dust between the front two elements (albeit minor). Everything else works phenomenally smoothly anyway.

SMC-M 85mm f/2. Received with a hazy rear element assembly. Cleaned with naphtha, no joy. IPA, no joy. Acetone, joy. Managed to get it clear despite my initial concerns it could be element separation. Will keep an eye to make sure that isn't the case. Everything else is pristine. Little annoyed at myself for slipping a little with the lens spanner, so removing some paint from the periphery of the rearmost painted portion, but I didn't dink the lens so I'm happy.

Tokina RMC 28mm f/2.8. Received with muck, grit, a partially-removed sticker on the barrel and a sticky (read, stuck) aperture. Thought I'd use it as a practice lens seeing as they're very inexpensive. Managed to disassemble completely, cleaned up the aperture blades, cleaned out the grit and removed a little spent/congealed lubrication, reassembled, ensuring the aperture lever did operate. Initially I reassembled with the aperture dial on the squiff, so it and the focus ring were stiff. Disassembled again, snugged up with a bit more care and attention and it works smoothly, focuses correctly and stops down through all apertures as it should, as well as being clean. This one I'm annoyed I didn't take photos of...


Notes from things I've learned so far:
Always exert downwards pressure when using lens spanners. As is the case with screwdrivers, same applied to lens spanners. It really helps avoid any slipping.
If it isn't turning, don't force too much. This sounds a little counter-intuititve, but if you can't do it with reasonable force you're only likely to slip or damage something if you over-try. It's also a good recipe for stripping screws.
Get good tools. The Moody JIS screwdriver set, and 'Engineering' brand flat-head screwdriver set are both solid pieces of kit, so I'm not concerned that I'll chew up the heads.
Look at element diagrams! This will help you decide on whether to go for lenses, especially when first starting out. If it's 4 elements in 4 groups, you're not going to worry about separation.
Give yourself time. Rushing = mistakes.
Give yourself space. No room to work in = mistakes.
Wear gloves.
Know the chemicals you're handling and how to handle them safely.


I think I'll be looking to get a couple more nifty-fifties before long to clean up. I fancy an A-50/1.7 again after selling mine a while back.
For those of you using acetone be careful it doesn't eat away at the balsam cement in between your element and ruin your day.Use Zippo Lither fluid followed by alcohol using Kim wipes

02-16-2020, 05:17 AM   #50
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Minolta 35mm f2.8 HG

Well I have been working on this little horror for almost three weeks.

Lens was sold with working focus (actually very smooth) but aperture stuck and internal elements VERY hazy. External front glass looked like it had been sandblasted. Fungus present in rear elements. Inner elements hazy.

The Minnie HGs are notorious for oiling up and the aperture fix was easy by getting the diaphragm out and giving it a long soak in IPA. Interestingly this lens was not at all internally like any on the videos and guides but having done a fair few lenses now it wasn't that hard to figure out.

Fungus in the rear groups was easily solved with a peroxide bath, a wash down with IPA and finally some water. Left to dry, polish and reassemble.

The front elements were a a complete nightmare. The front most element was cleaned up as best as was possible with a long soak in peroxide, a long soak in acetone and finally an IPA bath overnight followed by a wash down with water. This process had to be repeated about 6 times before the lens started to shine a bit. It still has some scratches and pock marks but nothing that I think will likely impact performance. The second element from the front was a different matter entirely.

The second element had suffered some kind of reaction between its coatings and the oil. Minolta used a magnesium base for its coatings and I suspect damage to the coating in a few places had allowed the magnesium to react. As a result the glass looked ok to the eye but put a torch on it and it was like frosted glass. The first pic under the red light gives an idea. Actually the area that looks fogged was in fact the clear bit, weird optical illusion caused by the lens being wet from an IPA bath when I took the pic the apparent clear bit was in fact almost opaque caused by the coatings having extreme haze and d=showing a lot of scratch marks (I suspect someone had tried to clean it using poor technique or materials and caused the coating to be scratched and thereby exposed the coating underlaying materials to attack by the oil). The only answer was to try and remove the coatings altogether and this is where it got horrible, over two weeks I soaked the lens in acetone, peroxide, IPA, oil, hand cream, ammonia, dilute household bleach and even resorted to heating it to make the coating fail. It did start to go after 5 days in a strong acetone but only after it had been left for a day soaking in hand cream which seemed to really help.... the second two pics under blue light show the progression of the coating starting to rub away with each subsequent polish. The final stages involved gently polishing with cotton wool balls and q tips in a nice even manner over 3 successive nights while the lens bathed in acetone during the day until eventually...........huzzah it was clear.

Final pic is of lens finally assembled. The coatings are gone from the front two lenses but considering they were fogged to hell it can't perform worse. Initially looking through the lens gave a view as if you were using an intense soft focus/glow filter and at least now it shows a true and sharp image.

All that remains is to film test it.

Honestly there were times doing this I was inclined to give up but it just goes to show that persistence pays even when you are sure it won't.

Last edited by Astro-Baby; 05-09-2020 at 06:33 AM.
02-16-2020, 07:39 AM   #51
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Cool! Nice to see you eventually beat the Minnie to submission!
I have no idea why but, don't we love these challenges?
02-16-2020, 11:07 AM   #52
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Ismael, thats two minnies I got back from the dead recently, both with similar coating issues. Unfortunately the Pentax lens never made it. The coatings are shot, I think fungus may have etched the glass plus I am now nearly certain it has balsam seperation. I couldnt see that before but the lens was so bad it probably just didnt show. I have considered getting it apart and doing a new balsam job as a learning experience but dont know if I can be bothered.

Challenges, I can live with out them, my XD7 packed up yesterday and thats even more work ro add to the pile

But yes its a good feeling when you finally get what was a piece of junk to actually perform ok......I like the conservation aspect

03-09-2020, 07:15 AM - 1 Like   #53
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QuoteOriginally posted by ismaelg Quote
A good clean and everything went back together.
Truly impressive stuff as i continue to traipse thru this thread. I seem to make things worse when I try to fix lenses, so I would appreciate either (a) some more detail on what you did and/or what you used to revitalize these old lenses, or (b) your address so I can send some stuff for you to fix up for me. Seriously, we used to have a great guy on here that reanodized lenses silver, black, or other colors and did fantastic CLA jobs on them. I sent him one, but regret never getting around to sending more because he vanished. A couple of guys like that on this forum might end up with a decent side job.
03-09-2020, 09:32 AM   #54
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any recommendations to get the name ring off of a K series 135mm lens?

Mine is really stuck there. and I want to clean it.

I do not want to use the spanner because it is so stuck that I know I will scratch the name plate.
03-10-2020, 12:23 AM - 1 Like   #55
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Edom......my approach would be to apply a small amount of IPA around the rim repeatedly, this may loosen any dried oil or drek thats gotten down there into the threads. Repeated applications but apply with a small clean brush. Dong put so much in that it could leak into the lens housings.

If that didnt work I would apply a hair dryer to the sides of the lens where the name eing screws in. Gradually increase the heat and periodically try with the spanner. I often find a bit of heat will work wonders.

When using a lens spanner dont turn the spanner, keep the pressure down on the lens by having the lens on a solid surface, press down with the spanner/spanning wrench and gradually apply torque on the lens NOT the spanner. If the spanner slots are very shallow put some low tack tape over the lens in case of slippage.
06-07-2020, 03:39 AM - 2 Likes   #56
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Getting some done....

I am terrible at taking pictures while I work, I either get so involved I forget to get the pics or I find taking the pics distracting and it breaks my concentration.

Recently yhough I HAD to take pics but there are thousands and most did not come out so well as I was working late at night and the digital happy snappy let me down. Anyway I have been working on a couple of lenses that have been bad news for various reasons. Heres a Helio 44 that came to me in awful shape. The Leningrad tractor factory who made it did an awful job and 50 years had not been kind to it. The lens had the most dreadful oil contamination I have yet seen made worse by the fact the oil had dried like tar onto stuff. The grease used was like black goop throughout.
I have to say this lens is an absolute horror to work on (Ismael be warned on this one ). My thanks to Thomas Glavina for his guide but the guide only takes you so far. The lens is horribly complex, contains very many tiny screws about the size of a molecule, there are complications both in take down and assembly and getting the lubricant mix right for the different elements is an art. It needs about a gallon go oil - grease for the aperture ring, grease for the stop down ring, grease for the helicoids, grease for the helicoid housing - and all of them have headache factor - too much and it all goes stiff, too little and stuff wobbles and grinds. God only knows how the poor factory workers ever got these assembled. Thomas Glavina makes it look easy - dont be fooled. If I had known at the start what a complete swine this lens was going to be I would have eBayed cheap as a 'sold as seen' but once I start on something the OCD takes over - this thing has had two weeks work every night.

Anyway heres a pic of some of the internal components and the finished product. The pic of it at the start didn't work out so well. The guts on display here are not the entire components only the internals bits and the teeny tiny screws aren't show at al plus the small parts needed to make it work - this lens probably had more parts in it than any three Japanese lenses.

It came out ok - I am not crazy about the smoothness of the focus but I honestly dont believe anyone could get it better plus once cleaned the glass showed small bubbles in two of its elements - these must have been there when it was made as the bubbles are clearly inside the glass. Every single glass surface was cleaned and polished - thankfully the grease seemed to have stopped any fungus ever forming.

The pics of the bits is AFTER cleaning - that brass ring was so black with goop I initially thought it was an enamelled part !!!! The triangular looking bit second from left at the back is the front element housing. The small part to the extreme right at the back is the rear element group and the part on the middle of the middle row is the iris assembly - the big bits not shown are the focus ring and the stop down rings and two other internal rings - when you add on the dozen or so small screws, the roller bearing and the aperture assembly parts you get an idea of just how many parts there are in this thing - absolutely not for the faint hearted and there are booby traps galore on reassembly. I had to rebuild this three times and every time is a stress that this time round one of those tiny screws will break, cross thread or strip.

Its probably had about 40 hours works to get this to come to pitch perfect plus every tool in my arsenal
Attached Images
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DMC-TZ70  Photo 
View Picture EXIF
DMC-TZ70  Photo 

Last edited by Astro-Baby; 06-07-2020 at 04:09 AM.
06-07-2020, 03:55 AM - 3 Likes   #57
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And heres No.2

I didn't get any shots of this one while it was in bits - this one came with a broken Chinon CX camera that was beyond repair. The lens had multiple fungal spores, the rubber grip looked almost white, the aperture mechanism was jammed (iris closed and aperture ring locked up). Focus helicoids were almost seized it was so hard to get it too turn.

Thankfully I have worked on a close sister of this lens, a slightly later version. I initially deemed this one beyond repair but started messing with it on a Sunday afternoon. Two days later it had started to come good and a bit more work bought it back to near mint.

All the glass was soaked in peroxide and thankfully the fungus hadn't caused any etching, glass then cleaned down with IPA, washed out with distilled water and finally polished, exterior glass given a shot of Optical Wonder which always gives a great finish I find. The barrel work and non glass surfaces were given a bath in a very dilute peroxide, bath in IPA and fresh water before polishing and cleaning out. Aperture mechanism problem was somehow the aperture ring had got out of kilter and jammed - like it had been forced perhaps. Iris sorted out with a soak in IPA to remove grease contamination. Case work exposed to powerful UV lamp for a few hours to bring all of the white lettering out. Some of the lettering and markings was so dirty when I got it I initially thought they had worn away but a nice soft scrub with a tootbrush and clean out with a softened bamboo skewer followed up by the UV hit bought the paintwork and trim up.

Rubber grip was cleaned and polished with toothpaste (Colgate Gel works well) and then cleaned with a rubber restorer and finally reassembled, helicoids re-greased and focus zeroed for infinity and hola ! - Here she is.
Came up almost like new. Very pretty But after about 10 hours of work (not including soak times) it should be
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DMC-TZ70  Photo 

Last edited by Astro-Baby; 06-07-2020 at 04:10 AM.
06-07-2020, 05:26 AM   #58
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When I clean the ELEMENTS i use ZIPPO LIGHTER FLUID and Kim Wipes and Rocket Blower. Always use the rocket blower first
06-07-2020, 07:15 AM   #59
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I usually rocket blow and gently brush first and then use a small hit of Baader Optical Wonder on a cloth. Thats just for initial inspection.

If I am going to have to deep clean ( ie there is fungus or some other horror ) I normally go for IPA or Peroxide ...IPA if its oil, Peroxide if its fungal. If I end up using Peroxide I tend to run the lens through a quick IPA wash as well and then a bath in distilled water ....not if they are cemented doublets. For cemented lens I usually apply a dampened cloth over the lens, dampened with peroxide or IPA.

Experiences with Minolta lenses are that if there is ANY coating damage dint let the lens get soaked, the coating reacts super badly with IPA.

Once allall the nasties are off if its an internal lens I give it a polish with my super fine cloth and insoect under a glass with a torch, rocket blow it and brush as needed to get it super fine.
If its an external facing element I usually polish with some optical wonder, brush and blow to get it minty.

Generally I try and do as little as possible and not take internal elements to bits unless I have no choice.

Over the past six weeks or so I have these two above plus a Tokina 24mm, a Vivitar 28-70 zoom and three Minolta MD types. The Tokina would have given the Helios a close race for being an arse to work on. Terrible tough lens to mess with.

Minoltas are my favourite to work on, they are usually simple and not much grief apart from some of the very early MC ones which seem to suffer a variety of ills mostly related to coatings.

Next one up is a Nikon E series which I am dreading and keep putting off
06-07-2020, 07:47 AM   #60
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yes Minolta Lens are delicate
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