[BigMackCam]

I've just started work on a Helios 44-2 that needs the aperture blades cleaning, and a general clean and helicoid re-lubrication.

I'm having trouble separating the optical and focusing blocks. From what I've read, by grasping the preset and aperture rings together and twisting the optical block anti-clockwise, it should unscrew.

When I first tried this, there was no movement at all, so I gently heated the whole lens and then I was able to get some movement - but, there's a lot of resistance and I can feel a clicking as I rotate it. It feels to me like there's one or more screws holding the two blocks together, but I can't for the life of me locate it (or them). I've taken off the focusing ring and tried to remove the depth-of-field scale, but with all three screws completely removed it will freely rotate but only move back and forth by 1mm or so.

If anyone can guide me as to what I may be doing wrong, I'd be grateful. I'm reluctant to use brute force unless that really is the only way

[madphys]

I hope this can help

You Tube

You Tube

Anyway - the keywords you are looking for are: Разборка Гелиос 44-2

[chuck_c]

I recently acquired this lens and will have to be doing this as well. I found this video on YouTube that may be of some help. It is considerably longer than it needs to be, as the tech who is doing it has you watch him clean and dry each individual aperture blade as well as some of the other parts, but at least he is speaking English.

Youtu.be

Youtu.be

[BigMackCam]

I hope this can help

Anyway - the keywords you are looking for are: Разборка Гелиос 44-2

I recently acquired this lens and will have to be doing this as well. I found this video on YouTube that may be of some help.

Thank you both for the YouTube links

The two halves of this lens may be cross-threaded or have the threads otherwise damaged. Since you are cleaning everything anyway, if you have the optics out, you could try spraying some penetrating oil into the thread to see if it loosens.

The only other thing I can think of is that perhaps this is an odd variant with a retaining ring that can be accessed from the rear and prevents the two halves from turning apart. I've never heard of this lens having one, but a lot of the Eastern European lenses have them, so it might be worth checking on the off chance this sample has one for some reason.

Thanks, Brian...

In fact, heat and brute force won out... I've managed to get the two blocks apart exactly as I had previously read (and confirmed in those videos), but it took a major effort. It seems the problem was a thin shaving of metal that was fouling the threads - see photo below... this tiny fragment was stuck in the threads of the optical block. Perhaps from when the lens was manufactured, or last serviced. With that removed, the two halves now screw back together and apart again easily

I'll take a break before I continue... but hope to get the aperture blades cleaned this evening

Attached Images

 

[BigMackCam]

Well, the aperture blades are done. First time I've attempted it, and it was more fiddly than I expected. Cleaning them was... OK, I guess, but there must be a better way than isopropyl alcohol and a cloth. Reassembling them was a bit infuriating, but I think I've got the knack of it now.

That's it now until tomorrow, when I clean the glass and helicoid, and re-lubricate... The easier bits

[BigMackCam]

If you disassemble the blades, then the easiest way to clean them is to drop them in a bit of organic solvent like acetone, mineral spirits, naphtha, etc. and let them soak for a bit. Just beware that acetone is hydrophilic, so if you leavet hem in there too long, they can rust.

Thanks, Brian, that's useful to know. I'll get hold of some naptha, I think. As it is, I cleaned each blade individually, with isopropyl alcohol and an old lens cloth. It was time consuming, but worked - the difficult part was getting the oil from around the little nubs.

When using solvent to soak the blades, I assume I need to flush them clean afterwards? Or does the solvent residue just evaporate?

Cleaning in situ, I've heard that some have successfully used brake cleaner.

Not an option in this instance... whoever services the lens last must have used a very light oil, as it was thin and had flowed *everywhere*. I'm having to dismantle every single bit of the lens and clean it. It's good experience, I guess

Once you step up to preset lenses with higher numbers of blades, it becomes increasingly fiddly. On some, it even makes sense to grease the blades to hold them in place while you put them in, then soak the whole thing in solvent afterwards to clean the grease back out. While it seems counterintuitive to disassemble if you are just going to regrease, it is still worth doing to remove solid grit and grime particles that may have entered the mechanism.

Interesting. Hopefully, I won't be attempting anything much more complex for a little while... my lenses with larger numbers of blades are currently oil-free, but this is handy to know for when - inevitably - I have to service one of them.

Thanks again for the pointers - very useful

[Helios 1984]

Thanks to the information you provided, it took me less than an hour to clean my 44-2.

[BigMackCam]

Thanks to the information you provided, it took me less than an hour to clean my 44-2.

Glad to hear it, and may I say what a fine job you've done!

[Helios 1984]

Glad to hear it, and may I say what a fine job you've done!

Thank you.


Now that it's clean, I'll have to screw it on my Praktica and shoot a roll with it.