RZ67 lens disassembly?

[TimmyMac]

So I've got an RZ67 180mm lens with a little edge separation - apparently a relatively common problem with this lens. Either the front element retainer is screwed SUPER tight, or there's some trick to getting it off. I've seen at least one other APUGer who tried but couldn't remove it. Any ideas?

 

[John Koehrer]

Try a drop of alcohol along the edge of the retaining ring.
Sometimes it also helps to change position where you're putting pressure on the ring. I just use a rubber stopper & move from section to section around the ring.

 

[paul ron]

Which series 180mm lens are you talking about?

How many of these lenses have you seen with edge seeparation?

The retinaing ring you refer to...is that the name ring aka decorator ring of the front cell?

 

[ShaunQ]

I'd like to pull apart my 110mm 2.8 sometime really soon, there is a large visible hair inside the rear element that doesn't show up in images, but bugs me all the same. So thanks in advance to anyone that can share information about the disassebly and reassembly process of RZ lenses.

 

[thisismyname09]

In my experience with RB/RZ67 lenses, they're just put together extremely tightly. Just keep trying, take a few breaks, try again; it should eventually open up.

 

[EdSawyer]

110

I've not had the 180 apart yet but I opened my 110 once to clean out dust. The whole rear cell unscrews from the back, a spanner helps but not 100% required. usually any dust/etc. is between the cells in that lens, so pretty easy to clean.

-Ed

 

[ShaunQ]

Thanks Ed, just had a look at the 110mm and although I didn't have the official Mamiya spanner, I carefully used two small flat head screw drivers and with a bit of even force managed to unscrew the rear element, and remove the dog hair that was sitting loose in there. I really do love the construction of Mamiya equipment, beautifully machined and crafted, yet easy to maintain and repair due to their mechanical nature. Below is a picture showing what I did for future reference, all unscrewing was done anti clockwise and reassembly in reverse -

.

 

[EdSawyer]

Shaun - nice work, sounds like you got it done easily. That lens (110) comes apart pretty simply if you are just removing the rear cell.

to the Original poster, re: separation in the 180 - try going in from the back. That lens is a tessar and the only cemented pair are the rear two elements, so if there's separation, it will be there. Plus going in from the back will be easier as there are exposed spanner slots most likely.

Micro-tools.com (I think that is the URL) sells nice optical tools like spanners and whatnot.

-Ed

 

[TimmyMac]

180mm f/4.5 lens for the RZ67. I've personally seen two, and more on ebay and forums. The name ring is around the outside of the lens barrel - I'm talking about the ring that holds the front cell in.

I'm 90% sure it's the front cell that has the issue. I know that it's a 4/3 design which would suggest tessar, but the separation (or maybe it's an oil film of some sort?) is on the front cell for sure. Anyways I tried to get in from the back but there are no spanner notches or anything at all to suggest that would be easy.

 

[EdSawyer]

I'll look at mine tonight. If it's in the front cell, it's not separation, since the only cemented pair is in the back. The RZ67 lens manual has diagrams of the optical formula, so this is pretty much a fact. The question is are the front 2 elements together in a cell or independently held in with retaining rings.

Having the right tools is key. At a minimum I'd say a nice spanner with various tips and a set of various size rubber stopper type rings.

Posting a picture of the lens in question would be helpful.

-Ed