Want to clean an Heliar

[F64]

Hello,
I bought an Heliar 1933/4 150mm in a Compur shutter and Bergheil bayonet. It is seems foggy and dirty in the internal part of the rear lens. Performance is not consistent with another 1950's Heliar I had.
Maybe cleaning it would make things better. I have little experience (Trioplan, Eurynar), and I am a bit wary. What am I to expect, if I remove the rear part? Would you advise trying it?
Thanks for helping

[Jim Noel]

No. Take it to someone who knows what they are doing.

[F64]

Thanks

[Tim Deming]

It should be easy to disassemble and reassemble if you want to clean it. If you have good materials ( cloth and solution) to do so, it's a very easy job, if not, then probably better not to do it. I've probably cleaned 100s of similar heliars

[Peter De Smidt]

Tim, what's your process for cleaning them?

[F64]

Yes, please.
I had no problem in disassembling into two parts: front and rear. The rear assembly seems easy to open, but luckily it was clean. The front assembly has no cuts for the wrench and I am a little wary of applying torque.

[RSalles]

Sacco,

You'll probably need a rubber grip with the size of the front ring to turn it. Some years ago I bought a set at ebay.

Cheers,

Renato

[F64]

@RSalles: thanks. I will take a look at it, but it's getting more involved that I expected.

[Toyon]

Could be that some of the problem is with the cement. That can't be cleaned.

[mdarnton]

The front and rear components are both cemented pairs, so nothing needs to be disassembled on them. You already figured out that the back section doesn't need to be disassembled to be cleaned, I assume. On the front section the rearmost element--the fifth, middle element, should be removable separately. I think on my lens the whole back end twists off the front part of the barrel, with the middle element..... I think. It's been a while. Once that's off, you can clean the back of the front component without taking it out of the barrel.

Mine is just like this video. I don't know why the person in this video takes the front component out. You can see by the trouble he's having why you shouldn't:
https://www.youtube.com/watch?v=JS2N1696iWc

Don't get things so wet that cleaning liquid snakes up the edges of the mount and attacks the cement. You don't have to soak a lens to clean it. That's a good policy when cleaning any lens without disassembly as you do in the normal day-to-day of things: go easy on the liquid so it doesn't go places you don't want it to.

[F64]

@mdarnton: Thank you. I was not planning to disassemble the front assembly completely, as the fog is in the internal surfaces. However, the assembly is not designed in a way that invites opening: difficult to find a grip.

[mdarnton]

I must not be like mine or the one in the photo, then, because on ours there's quite a bit to hold onto, though it's not provided with tread. You might find wrapping a couple of rubber bands around the back gives you a better grip, if something is frozen?

[F64]

As we all know, a picture is worth a thousand words


this is the front assembly from the rear

150077

This is the lens

150076

[Tim Deming]

The middle element Will screw off, the giveaway Is the knurling on the edges in your top foto. There are different techniques to grip the knurled edge and if its stuck. Some may wince, but i find slip-jaw pliers with rubber in the jaws work well to get a good grip, while the rubber prevents damaging the brass.

Second the comment about avoiding too much solution. I use diluted windex in water, then water, but always spray fluid onto fresh lint free tissue before applying to the lens. Dont squirt fluid on the lens directly

[F64]

I will try. Thanks a lot.