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View Full Version : Assistance with an iris type lens clamp please



numnutz
13-Jul-2010, 09:27
I recently acquired an iris type lens clamp. I am quite happy with it in general. In the past someone has greased the iris, the grease has attracted some grit.

When the iris is opened and closed the movement feels gritty, I don't want to cause any damage to it so I decided to clean it assembled. I washed it through with Naphtha and cleaned it as best as I can but there is still some gunge in between the blades I cannot reach. I really think that I should disassemble the thing completely and clean each individual blade.

I am sure I can do this but I cannot figure out how each leaf actually fits in relation to each other. After all it is easy to dismantle something and never quite so easy to put it back together. :eek:

Does anyone have a link or an illustration showing something similar that I can use as a guide. Or can anyone offer advice.

nn :)

Robert Oliver
13-Jul-2010, 09:34
take detailed pictures of your iris before you take it apart... constantly refer to your photos as reference. I took mine apart and cleaned it. I don't remember it being very difficult.

Jim C.
13-Jul-2010, 10:58
I took mine apart to clean since the movement was stiff and the blades had a little rust,
once I had mine apart I flushed parts with WD40, the stoddard solvent in WD40 should
get all the old grease off and I used scotchbrite ( 000) to get the rust off.
All the parts were wiped clean dry of WD40 before reassembling.

Like Robert said, take pictures and make a note of how the blades interleave with each other,
and the pivot pin positions, the last leaf is a bit tricky to get back in.

Mark Woods
13-Jul-2010, 15:03
Soak it in kerosene over night. Move the blades occasionally while it is immersed. The grit will come off and when you dry the iris off, the kerosene will lube it. I've done this to some old lenses I have and have had no problem.

alex from holland
14-Jul-2010, 10:25
Only use graphite powder for lube (aparture) blades.
Never use any kind of grease before assembling (only for cleaning)
The lube will atract dust and within a few months you can start whole over.
so make sure you get of ALL the lube before putting only a tiny bit of powder on it. After that wipe the most of it of with a clean towel.

alex