Broken zoom ring on sigma lens. Could I fix it?

[zootshooter]

<p>I have an old sigma 70-300mm lens. Recently the telescopic zoom has ceased to function. It is now stuck at 70mm zoom and turning the ring does nothing, only the focus ring now functions. I took it to a camera shop and they quoted me 150 euros to send it off to sigma to fix it. For a lens that costs less than that it's not worth it, so I wish to fix it myself. Is this possible? could anyone provide me with any guidance as to how I could do this?<br>

Cheers</p>

[scrivyscriv]

<p>You are probably more likely to cause more damage to the lens if you open it up. It could be a simple problem that you could easily fix, but if the lens functions for you at all, you risk losing even the 70mm you now have if you forget/misplace/lose/drop one of the small parts. And there are a lot of small parts.</p>

[zootshooter]

<p>Thanks for the response Robert, you are almost certainly right about the problems i'll face in trying to fix it. But the 70mm alone is worthless to me, so I'm willing to risk breaking the lens if there's any chance I could get the zoom functioning again. Anyone with any ideas about how I should get inside the lens and what I should be looking for?</p>

[steven_f1]

<p>You might get a better deal by bypassing the middle man and sending it directly to Sigma. Otherwise I would ask if assembly drawings are available. I would be reluctant to take it apart without an assembly drawing. Another thing to consider (if it is an old lens) is if parts are available for it. If there is a broken part inside that is not available there many not be any way to get it working again. </p>

<p>Either way you need more information and Sigma or an authorized Sigm repair center would be the place to go to get that information. Ask them how much it would cost to repair. If you want to try it yourself ask for assembly drawings or information on how to take it apart.</p>

[jimstrutz]

<p>I'd tear it apart. If for no other reason than the little bit of education that it might provide. And who knows, you might see what the problem is, and be able to fix it on the spot. I wouldn't count on it though. But if it's wrthlesss to you now, and it's not worth repair, why not have a go at it?</p>

<p>Sigma has been known to use glue and/or tape in the assembly of some of their low end lenses. Have fun.</p>