Kenko extension tubes - focusing

[Joe T]

Hi all

I got my Kenko extension tubes this morning. When I stack more than one tube on any lens (have tried my 50 1.8 and 105 2.8) turning the focusing ring on the lens becomes noisy and stiff, almost 'gritty' but not quite. I assume that it is the focusing screw not rotating properly in and between the tubes.

Has anyone else had this problem? Will it free up over time? It is worth trying some kind of lubricant, e.g. WD40?

Thanks all.

 

[Joe T]

Ignore

 

[Canon Bob]

Ignore

Do I detect a hint of self-certified plonker ?

 

[Joe T]

Do I detect a hint of self-certified plonker ?

No, just ignore that post. The first post still stands!