Iron ring on brass lens - possible to get off?

I think it could make a grown man cry and I think it might be a basket case, but ...

I happened to bid (oh well) on what supposedly should have been a nice little wide angle Aplanat.

Once the package arrived, the troubles began. From the photos on the auction site I had figured there was some sort of hood sitting on the brass lens. Never thought to ask the pertinent questions.

Some time in the past, someone (dim-witted) has put a piece of iron on to the front of the brass lens. And it does not budge. I just sit here and wonder if it would be possible to get rid of the junk?

Have a look at the photos and see what you think.

My hunch is that it is a Rodenstock, by the way.

Yikes!
That appears to be soldered on.
Maybe see what SKGrimes would recommend.

Looks more like some kind of epoxy. That would take a very light touch with a dremel or a grinding burr to split the iron ring to allow removal. I doubt the glass would have tolerated soldering heat.
Any chance the front ring can be unscrewed?

I think it might be possible with the right rubbery tool to get the front cell off, but I haven't found anything useful at home yet.

On the outside of this iron ring (feels like something an old plumber would recognize from under the crusty old sink in the cellar), there was a piece of thinner metal, which I was able to get a grip on with a piler, just rolling it off. It may be that this "lens hood" part was once soldered on.

I guess the first step is to back the front cell out, without marring the optics.

In model engineering, they use a saturated solution of alum to remove iron/steel broken taps and screws from brass. But in that case you need to be sure there is no other "iron" part other than what you want to remove. So taking it apart is the first step. And it won't get rid of the solder. Also nu idea is the sort of brass makes a difference.

Use it at your own risk...

Remove lens cells.
Check aperture leaves are metallic!
Use propane flame to heat the end with the iron/steel ring up.
Let the brass assembly fall out due to gravity when the solder is molten- holding the steel ring in pipe wrench or similar.
This kind of soldering is very difficult, so the real contact will not be so Large.
Then repeat after me - “Next time I must check all photos in the listing” 50 times!

If you have access to liquid gas under pressure (CO2), you could try shrinking the brass. This would break contact with steel due to brass having a high expansion/contraction index compared with Fe. Safety precautions are necessary with either method.

Hah, Steven, I am up to the 49th time now ... :)

Heating occured to me, good idea, but first I have to get the rubbery chicken out and rub the front cell. :)

you should ask yourself why this is there in the first place and do you really want to remove it and find out ? perhaps the underlying brass barrel is/was broken and repaired with this crude piece of metal ?

If you don't have a torch but only a solder iron, you might take off the solder in little steps using desolder pump aka solder sucker (https://www.amazon.in/Solder-Sucker-.../dp/B0002KRAAG)

Quote:

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Originally Posted by seven

you should ask yourself why this is there in the first place and do you really want to remove it and find out ? perhaps the underlying brass barrel is/was broken and repaired with this crude piece of metal ?

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Yes, that is a possibility of course. If I get the front cell out, I may be able to have a look if something seems odd from the inside. As it is right now, I have no way at all to (easily) ascertain the f/stops since they are hidden from view by the iron ring.

What is a bit odd to me, looking at it, is that the aperture does not open fully, as if it was restrained at f/12 (which is the designated speed).