Oops Help.... Sigma KPR

I dear well maybe someone here can help or at least point me in the right direction.

On receiving a Sigma 28mm mini wide II I realized that it was the KPR version. Having just removed a pin from a Sirius KR lens I thought no problems I'll do the same with this one. So all too hastaly I set about doing it and indeed was successful in removing the pin. Big problem being that two small springs (straight wire bent in a loop type) came out and a bearing that must have something to do with the clicking of the apertures. I can get the idea of what the springs need to achieve but just cant see how they go.

Does anyone have any experience of doing this or have the lens and the know how to look point out where things sit.

Or am I doomed and have to take this one on the chin????

Thank you in advance.

I can try and post pics later if that will help.

Stephen

The bearing usually goes in a tiny hole with a spring underneath, which presses it against notches on the inside of the aperture ring to provide the "click" at each aperture stop. Try holding the aperture ring to the lens and looking for the notches, which should give a hint as to where the hole is.

The two springs may well be what Sigma use to hold the lens in "A" mode, I've only dismantled Pentax lenses though and they use a pair of metal strips. Basically, pressing the A button needs to push them down to unlock the aperture ring and allow you to turn it. If you can work out where the A button ends up then you might be able to work out where the springs belong.

At least it sounds as if you didn't drop any bits (as I, er, may have done in the past).

I'm afraid I haven't disassembled a Sigma lens either, but have found that the mechanism used to link the "A" button/setting with its associated contact on the mount uses a second ball-bearing on some lenses. If the aperture ring still clicks between f-stops, it may be this one that has fallen out on yours.

Well it would appear that once out of panic mode I was able to come back to it and work out how it pieced together. Also a decent adjustable table light, a white tray and steady hands helped.

I found the very very small hole where the bearing did indeed sit on top of a spring, great care was needed for it not to move while placing things back together (small drop of grease would of made that bit easier).

As for the springs I needed to think outside of the box and then realized that one folded back on itself and and on both the arms needed to be the other side of the (thingys??) to apply the needed pressure.

So now its all back together and fully working. The 'A' mode works fine and all the apertures and half stops click into place well.

The pin was removed and the lens comes on and off the body (GX-20 in this case) and locks in place. Tomorrow I have a MZ5n arriving so will check its all fine on that body also.

Thank you for looking in and in the future if anyone needs some advice with that job let me know as it all seems too easy now its done.

Stephen