Novoflex Noflexar 35mm disassembly

[Jonny]

Slightly off topic, but I know this is a popular lens here. I've recently gotten hold of a copy of this which seems not to have the macro extension built into it. Determined to find out if it was stuck or perhaps just a different Noflexar 3.5 35mm I started to take apart the rear mount.

 

My only reference for this is here:

http://www.savazzi.net/photography/35noflexar.html

 

Where the lens is pictured without the mount. I haven't got photographs to hand but I can take some to show where I have gotten with this, but essentially here is what I have done

 

Removed 4 screws holding M42 mount in place

Removed 2 screws from under M42 mount connecting mount to helicoid

Removed 4 grub screws holding on "made in Germany" ring

Removed 4 grub screws holding focus scale in place (shouldn't have done that...)

Unscrewed the ring which has the hard focus stop on it that the mount was fixed to.

 

Now I can't see where to go next without removing the lens assembly, the focus scale can't be removed as there is a metal ring behind it, and I can't see any of the extension barrels.

[nfoto]

Pulling out the lens assembly might be the viable solution in the longer run. Been a while since I disassembled any of these, but from memory I recall a stuck one only got unstuck after everything was pulled out and put back again.

[Jonny]

Update:

 

The lens has previously been taken apart by someone else and put back together wrong.

 

After unscrewing the helicoid to mount fixing ring, the next ring (half of the helicoid itself) unscrews from the main lens body. Its tough because there is nothing to grip onto. You cannot use a lens spanner because the holes are fixed to the body at this stage.

 

After removing that ring, the other half of the helicoid is revealed. It is mounted to the lens by a single grub screw and four ball bearings. After removing the screw it can be pulled off of the lens.

 

On my lens the helicoid was not correctly aligned to the lens, and the ball bearings had ceased with rust causing them to stick. The lens extension is now removed ready for lubrication and reassembly. Once that is done I will removed the optics and clean them up.

 

I hope this is of some use to anyone else who takes this lens apart

[kogakunippon]

Dissasambling this lens is simple, but preparing it to work at infinity on my modified Nikon D7100 costs me some hours.... ;-).

[Andrea B.]

I've had my Noflexars apart more than once. The last time, however, I managed to upset all the aperture blades on one of them. Don't do that, please!

[Jonny]

What did you do to get it to infinity? I can't see a way to do it without shortening the helicoid?

 

What wasn't simple about this one was that extension mechanism was jammed onto the lens and took some time getting off. Oh, and the aperture fell out when I removed the front optics, putting that back together was tedious...

[Andrea B.]

One of my M42s is a Nikon mount so works fine at the infinity setting on a Nikon body.

The other is an M42 mount and works fine at infinity on the Pentax K1.

 

So you had the aperture accident too !!! I'm very happy to hear you were able to reseat those little critters. I was never able to get them replaced. Another member wanted to buy the lens and fix it. I don't know if he got it fixed, but I did give him a good deal on that Noflexar.

 

What camera will you use the Noflexar on? What mount is it? They originally were sold in F-mount, M42-mount and Exakta-mount.

[colinbm]

Oh, and the aperture fell out when I removed the front optics, putting that back together was tedious...

Hi Jonny

Any tutorial on how you managed to get the aperture blades re-assembled, please ?

Col

[kogakunippon]

My one came with the Exacta Mount which is the worse version of this lens concerning to the difference of the flange focal distance between Exacta and Nikon. But the quality at F8 is amazing. Perfect sharp from corner to corner, very impressive! I love it, my absolute favorit. Much better then the weak Kyoei or the Lithagon.

 

http://gallery.photo.net/photo/18250816-lg.jpg

 

http://gallery.photo.net/photo/18250815-lg.jpg

 

http://gallery.photo.net/photo/18250814-lg.jpg

[Jonny]

 

Hi Jonny

Any tutorial on how you managed to get the aperture blades re-assembled, please ?

Col

 

I'll try, but I didn't take any pictures. I won't lie it took a few goes and a lot of time.

 

There are two parts to the aperture, the seat in the lens itself and the brass ring that opens and closes the leaves.

 

I rebuilt the aperture on top of the brass ring in the fully open position,the first ones are easy but the last 3 you need to lift the ones you have put in already, in order to make them overlap correctly. A few times I did this and it all fell apart... It can be done though.

 

Once I had the aperture all together, open, on top of the brass ring, I set the lens (face down) to open, and put the aperture retaining screw into the lens, to the point where it went into the "slot" in the lens but would not foul the brass ring.

 

Then I aligned the "slot" in the lens which that screw goes through, with the one in the brass aperture ring, and holding the lens upside down, I balanced the aperture ring on my finger and guided it up into place. Once it was in, I held it and turned the lens the right way up again.

 

It was then a case of just fine tuning the leaves/blades to get them seated using tweezers.

 

The worst bit is the "upside down finger in the aperture bit", a round peg of exactly the right diameter would be much safer and I considered making one.

 

If you misalign the slots you need to remove and replace the aperture as it will not open/close correctly and there is no way to adjust it.

 

Hope that helps, its tricky to understand without pictures I imagine.

 

I wore latex gloves for the whole thing and cleaned the leaves with naphtha.

 

 

I was going to go all out Nikon F mount (mine was M42) but it needs a donor mount with 2 big holes drilled in the back to seat it and four little ones to mount it. Not got access to a lathe and I /think/ one is needed to reach infinity

[nfoto]

A good sample of the Noflexar can performs very well indeed. However getting such a sample might take time and patience.

 

Over the years I have had in my possession at least 7 samples of this lens. Most of them in the Exacta mount which apparently was the by far most popular at the time [in Germany]. Damage to the exposed rear element was common and in one case all the scratches made the lens deliver images with a perpetual 'fog' atmosphere mood to them. I quickly got rid of it; however, in hindsight I perhaps should have kept it for those 'special' moody shots? It was the M42 version if memory serves. Jamming or stuck focusing issues were encountered on every second lens and in the worst cases the lens needed a complete tear-down, cleaning, and lubrication.

 

For use on mirrorless systems, one can leave the factory mount in place and supply the lens with the dedicated adapter for the host camera. I preferred to make the lenses compatible with all my cameras, hence converted the Noflexars to 'F' mount (except the one sample already with such a mount, of course).

 

One sample in original 'F' mount has a very thin and recessed shroud keeping the rear element in position and this lens just barely clears the mirror on FX-format Nikons. One has to set the focus to the near limit before mounting the lens otherwise the risk is there of making contact with the camera mirror. On DX cameras the clearance is OK. It achieves infinity focus on all my F-mount cameras, though. The CPU-modification was tricky and required the expertise of my friend, Erik Lund (aka 'Dr., Lens') to be completed.

 

For the Exacta-mount Noflexars, the rear shroud is much more substantial and these lenses have issues on FX cameras. In fact, their rear parts can jam the camera mirror even after conversion. They should be considered DX lenses to reduce risks of jamming or damaging the camera mirror. I availed myself of access to a precision lathe in a machine shop and shaved off 2 mm of the rear lens casing after first have removed the Exacta mount. The guide screws for the helicoid need trimming as well. Depending on the thickness of the 'F' mount put in place of the Exacta bayonet, some shimming might be required as well. Older 'F' mounts form the '60s are about 1 mm thinner than the later AIS mounts. I did the machining first and acquired the spare mounts later, hence the odd shims requirement. CPU-modification of these lenses is a breeze because of the original 'F' bayonets on them.

 

Even through the Exacta-derived stock might cause issues with 'F' mount cameras, they will function without hiccups on mirrorless systems though the appropriate adapter.

[colinbm]

Thanks Jonny

That is a good description & I have tried that a million times......but I haven't got it just right yet

Oh well, I must give it another try again now that it is winter down under & I can spend some time inside.

I should make a 'round peg of the right size'. I have thought some temporary oil on the blades might aid assembly, then removing the oil when assembled & secured ?

Cheers

Col

[Andrea B.]

Heck I was ready to glue those little monsters in place !!!! Just kidding, of course, but geez is that ever tricky.

 

Col, I hope you can your aperture blades re-seated. I'm thinking that maybe we'd better send that lens somewhere to get it fixed?

[colinbm]

Yeah I have been thinking about getting a local camera tech to have a go.....

But I am up to my ears (with my limited finances) in getting an outboard motor boat together, to get on the water to get out & about into some nature photography & night sky photography away from city lights. It is winter down under & I am putting a new bottom in a 12' runabout, that I will be able to stay over-night in. Then I will get back into photography mode & get the lens working again.

Col

[Jonny]

A few drops of oil might help hold things together, but I think that it might be tricky to clean back out because of the way the aperture is sunken into the lens once assembled. Perhaps a few drops of Naphtha or alcohol would be enough to form some tension and then evaporate off without leaving any difficult residues. One thing I noticed is that even when 'secured' the aperture has a lot of play in it, until the front optics are back in, the retaining brass ring can move by a mm or so, which is enough for the leaves to jump out of place if they are disturbed

[colinbm]

Thanks Jonny

Yep some not too volatile solvent may be the way to go......

Col

[JCDowdy]

......getting an outboard motor boat together, to get on the water to get out & about into some nature photography & night sky photography away from city lights. It is winter down under & I am putting a new bottom in a 12' runabout, that I will be able to stay over-night in. .....

 

That sounds awesome! Please share some photos of your boat as well.

As an avid sportsman and naturalist I have seen so many things I wish I had documented. Running trotlines at night with Daddy, Grandaddy and Uncle in the Tallahassee and Tuscumbia rivers..... Fine memories there.

[colinbm]

Yes, thanks John, I sure will, that is my aim.

Also I have just posted a new topic for discussion 'Bioluminescence'.

Cheers

Col