Repairing a universal iris

[BarryS]

The killer deal I got on a universal iris might not be so killer after all. I disassembled the iris and found that some of the iris blades had popped their pins. Does anyone have any idea on how to reinsert the pins so they're firmly secured? Any idea on how the pins were affixed in the first place? The pins have a slightly smaller diameter base that inserts into the hole on the iris blade. They may have been pressed into a slightly smaller hole for a friction fit, but the ones that popped out freely fit into the holes and fall right out. Some kind of brazing maybe? It seems like they should be fixable.

[Vick Vickery]

Without actually seeing them its hard to say, but my first inclination is to think about riviting them (spelling?) with a sharp pointed punch after they are back in place.

[Steven Tribe]

I think the fixing of the iris blades to their axel is something to do with making the original assembly easier. I don't think a few loose blades will influence the adjustment, locking and tightness of the grip. Looking into mine, without taking it apart, indicates there isn't much lateral play available which would effect the function. But it is necessary, I think, that all ends of both "rings" of fixing rings have wider heads.

I have been extremely disappointed with the "security" of my new addition. It seems to me that the whole system, width of the blades etc. makes it only really useful for the older, wide and deep thread types. It just doesn't seem to lock well on later finer threads. Two of the blades have a little distortion but I find it difficult to imagine that this would effect the efficiency so much.

[Peter K]

Degrease blade and pin and glue it with a little dropplet of epoxy resin. If the epoxy is cured clean the pins etc. with a sharp knife.

[Keith Fleming]

Steven,

My approach to the "security" issue has been to use gaffer's tape on the threads of the lens. I believe that in addition to being more secure it also provides better protection for the threads.

Keith

[Stephane]

Instead of the gaffer tape, I use vulktape on the threads. It is some king of self vulcanizing rubber that only glue to itself. It works for me.

[BarryS]

Thanks for the suggestions. I'll try some epoxy first and if that doesn't work, I'll try to rivet the pins or rather--have someone with metal shop competence rivet them. This is my second iris and I find them very useful, but in a limited number of circumstances--for testing lenses and checking coverage, and shooting with small to medium lenses in the studio.

[eddie]

i have tried the epoxy...it did not do it. i have tried everything on these and studio shutters....not a good outcome.

but as steven says a couple here and there will still allow it to function....more or less.

try the epoxy. keep us updated.

[GPS]

The pins were probably pressed to the iris leaves. If they fall out you could ask a metal shop to make new pins with a slightly bigger diameter and let them be pressed there again.
And indeed, the universal iris is a crude device that is not a solution for all lenses, let alone the questionable parallelisms of the assembly...

[Steven Tribe]

I have received an iris clamp for repair (5 pins have gone) I will post a repair and servicing "guide" the next few days. Suitable for kitchen table workshops!