anyone take apart a Kiron / Lester Dine 105mm f/2.8 macro?

I've been trying to disassemble my copy of this cult-classic lens in order to redo the lubrication. I think i need to remove the branding ring before i can separate the helicoids. But i can't get it to come off.

Has anyone taken apart this lens?

Rings with no slots or holes usually need a friction spanner (i.e. a grippy bit of rubber) to undo them. You might also need to drip some acetone around the edge of the ring to dissolve some thread-locking adhesive.

Try the friction wrench alone first. Acetone can dissolve quite a few plastics.

These rings can be reasonably easy to unscrew, sometimes they need the treatment Joe suggests. Some are very tight indeed and won't succumb to friction. As a very last resort I've carefully drilled two small holes opposite each other, and clear of any lettering. A spanner wrench or similar engaged with the holes will usually then do the trick.

(I assume there are no slots in the ring though? Some have two small opposing slots to facilitate removal.)

Rings with no slots or holes usually need a friction spanner (i.e. a grippy bit of rubber) to undo them. You might also need to drip some acetone around the edge of the ring to dissolve some thread-locking adhesive.

 

Try the friction wrench alone first. Acetone can dissolve quite a few plastics.

Thanks, Joe. I've ordered a rubber-coated filter wrench that i hope will do the trick, but while waiting for that i'm going to try improvising with a length of insulated lamp cord and a stick to twist it around.

These rings can be reasonably easy to unscrew, sometimes they need the treatment Joe suggests. Some are very tight indeed and won't succumb to friction. As a very last resort I've carefully drilled two small holes opposite each other, and clear of any lettering. A spanner wrench or similar engaged with the holes will usually then do the trick.

 

(I assume there are no slots in the ring though? Some have two small opposing slots to facilitate removal.)

Thanks, John. That's a good idea as a last resort. I even have a Dremel to drill the holes with. There indeed are no pre-existing slots or holes to help with removal.

I've ordered a rubber-coated filter wrench that i hope will do the trick, but while waiting for that i'm going to try improvising with a length of insulated lamp cord and a stick to twist it around.

I've had luck with rubber 'O' rings of various sizes. One that fits exactly over the ring to be removed is obviously ideal.

Otherwise I might attach some rubber sheeting to a flat wooden stick with double-sided tape. The stick acting as a tommy-bar to get some leverage. The temporary tool doesn't have to look pretty! Or stay in one piece for very long.

I've been trying to disassemble my copy of this cult-classic lens in order to redo the lubrication. I think i need to remove the branding ring before i can separate the helicoids. But i can't get it to come off.

 

Has anyone taken apart this lens?

Sounds like a lot of work. Is the lens working at all?

I received the filter wrench from Amazon this morning, a rubber-coated, metal-core affair. It didn't work. The branding ring is too damn smooth for the wrench to get ultimate purchase on it. I'm going to try Dave's suggestion of applying liquid rubber to the ring and letting it dry first—although i only have rubber cement. Later, after work.

If that doesn't work, i'll try drilling two small holes in the ring and using a spanner.

Sounds like a lot of work. Is the lens working at all?

Yes, it works very well.

I've now tried wrapping the ring with double-sided tape and using the filter wrench. The tape allowed me to apply much more torque before any slippage occurred. It still was not enough to budge the ring, despite applying more torque than i've ever applied to any task of this type.

I think this is more torque than i could achieve using a lens spanner, so i see no point in drilling the holes to use one.

I can't think how i could increase the force any more. And i can't believe how tight this branding ring is screwed on! Maybe if i had a filter wrench with a much longer handle....

I think i'll have to be satisfied with the focus action as it is.

I'm probably stating the obvious, but mine has a set screw near the end of the barrel; it looks like its function might be to secure the branding ring.

Thanks. Removing that screw has no effect on the ease (or impossibility) of unscrewing the branding ring. Rather, it seems to be involved in the infinity focus hard-stop. When the screw is loose or removed, the focus ring does not stop at infinity but goes about a centimeter past it and stops with a "crunch" instead of a "snick".

It still was not enough to budge the ring, despite applying more torque than i've ever applied to any task of this type.

Then I fear that thread-locking adhesive is involved.

Most types will dissolve with acetone, some soften with heat.

Got a soldering iron?

If the ring and adjacent parts are all metal, then applying a soldering iron to get the ring really hot will possibly release any thread-lock and in any case ease the fit of the ring.

At your own risk, obviously!

Having said that, I recently encountered an old (1950s vintage) Zeiss Jena lens that had a cunningly hidden grub screw that held the nameplate from being unscrewed. Underneath was a conventional slotted retaining ring.

Too late to edit.

Another thought. It's not a LH thread is it? Unlikely on a faceplate, but you never know!

Too late to edit.

 

Another thought. It's not a LH thread is it? Unlikely on a faceplate, but you never know!

I'll try twisting the other way. Maybe after i receive the 3M VHB tape that i ordered yesterday. The VHB will allow me to torque the ring even harder than the common Scotch double-sided tape did. Also, since i received a pair of the filter wrenches, i'm going to try using both of them in concert—one on the branding ring, and the other on the rest of the barrel—so i can use leverage bidirectionally.

I've already dripped acetone into the gap. No help.

About the soldering iron—what would it do to enamel? I believe the barrel of this lens is unpainted, anodized aluminum... but i'm not 100% sure of that.

This link may have some more information to help:

KIRON 1:1 macro 105mm (100mm) repair

If you haven't looked already, there are also some DIY repair videos on YouTube for other Kiron lenses, that may give some insight on disassembly.

The Kiron 70-150 f/4 one-touch zoom has a similar name ring detail, but it's a little different in that the rubber grip is at the very front, adjacent to the name ring. Boggy's site has an on-line PDF of the parts list for that zoom, and the exploded diagram shows that the name ring is secured by four small screws hidden beneath the rubber grip. The 105's grip is much farther away, but based on what you have described, it seems possible that there might be some long tabs that extend all the way from the name ring to the grip.

In the Vivitar version of that zoom, the Kiron name ring is solid black, and the ring that says Vivitar is in a more conventional location around the front lens element.

This link may have some more information to help:

 

KIRON 1:1 macro 105mm (100mm) repair

 

If you haven't looked already, there are also some DIY repair videos on YouTube for other Kiron lenses, that may give some insight on disassembly.

Thanks, Dave. I had already seen the thread you linked to. But i will look for youtube videos as suggested.

The Kiron 70-150 f/4 one-touch zoom has a similar name ring detail, but it's a little different in that the rubber grip is at the very front, adjacent to the name ring. Boggy's site has an on-line PDF of the parts list for that zoom, and the exploded diagram shows that the name ring is secured by four small screws hidden beneath the rubber grip. The 105's grip is much farther away, but based on what you have described, it seems possible that there might be some long tabs that extend all the way from the name ring to the grip.

 

In the Vivitar version of that zoom, the Kiron name ring is solid black, and the ring that says Vivitar is in a more conventional location around the front lens element.

Roy,

Thanks for the advice—i had already read somewhere that another user had looked under the focus ring grip and seen nothing. That, combined with the fact that the grip is stuck on exceedingly securely, persuaded me not to remove it.

My version of the lens is actually the Vivitar 100mm f/2.8. It is indistinguishable from the Kiron, unlike the Viv Series 1.