After having intermittent problems like jammed SWM, intermittent VR for quite a while, my copy of 18-200VR finally died.
When I took it out of the dry cabinet to test before I bring it out to SBG, the lens refused to focus down to anything below 1m. It just got stuck.. So, hoping to be able to undo the jam, I exercised the lens a bit by manually turning the focusing ring and the zoom ring to and fro...... then it got worse... the zoom ring also got stuck..... :sweat:
Time to open up the lens to see what's causing the jam... My worst fears came true... The VR flex is the culprit of it all.
I stripped past the PCB to unveil the flex dressing. The lens cannot be used with the crumpled flex jamming the mechanism. So I continued to strip until I can at least get the flex out. Then I saw why the flex could fail. It was designed to fail!!!
The flex comes out from a slot on the optical tube assembly.
The slot edges are not rounded enough. Plus there is another tube which slides on the inside, so the flex is making a u-turn plus another step to the outside tube. This stresses the flex and will cause it to dislodge from the tube if the glue gives way like mine probably did. So when you zoom in and out, there will be tremendous movement on this flex.
Lastly, the focusing lever slides over the flex when the distance is <1m.
With these multiple mode failures, it is no wonder my most used lens gave way.
A word of caution to all users of this lens, when you zoom, zoom gently so as not to stress the flex too much.
Let's see if NSC is kind enough to offer me a free service for the failure of this flex.
When I took it out of the dry cabinet to test before I bring it out to SBG, the lens refused to focus down to anything below 1m. It just got stuck.. So, hoping to be able to undo the jam, I exercised the lens a bit by manually turning the focusing ring and the zoom ring to and fro...... then it got worse... the zoom ring also got stuck..... :sweat:
Time to open up the lens to see what's causing the jam... My worst fears came true... The VR flex is the culprit of it all.
I stripped past the PCB to unveil the flex dressing. The lens cannot be used with the crumpled flex jamming the mechanism. So I continued to strip until I can at least get the flex out. Then I saw why the flex could fail. It was designed to fail!!!
The flex comes out from a slot on the optical tube assembly.
The slot edges are not rounded enough. Plus there is another tube which slides on the inside, so the flex is making a u-turn plus another step to the outside tube. This stresses the flex and will cause it to dislodge from the tube if the glue gives way like mine probably did. So when you zoom in and out, there will be tremendous movement on this flex.
Lastly, the focusing lever slides over the flex when the distance is <1m.
With these multiple mode failures, it is no wonder my most used lens gave way.
A word of caution to all users of this lens, when you zoom, zoom gently so as not to stress the flex too much.
Let's see if NSC is kind enough to offer me a free service for the failure of this flex.