Problems with focusing ring of 18-55 pentax lens

[michellemandat]

The focusing ring of my 18-55 has not a free movement in MF mode. It's like sand in the mecanism. Has anyone

disassembled one of these to tell me how to do?

Thanks

Michel

http://m.lemandat.free.fr

[personalphotos]

Have you tried taking the lens off the camera and turning the MF ring? Is it still difficult to turn? If so then the issue is with the lens and I can't tell you much more other than to send it in for repair or get a new one if MF is important.

 

With the camera AF switch turned to MF the problem remains?

[andrewg_ny]

I guess you should count yourself fortunate that the lens doesn't also contain optical stabilization or a AF

drive motor (e.g. SDM, USM, etc.).

 

<P>Bear in mind that the 18-55 has quick-shift focusing and should turn fairly freely even if AF is engaged on

the camera body. I have found that some quick-shift lenses have a mild 'sandy' sound/feel when focusing

manually, also including the DA16-45 and D-FA 100 macro--but it sounds like yours is much worse--despite the

sound/feel, they certainly should still have free movement. Others like DA 50-200, DA 12-24, DA21, and DA70 are

smoother.

 

<P>I can't help you with dismantling it, but if you do try, I would be *extremely* careful about tracking each

piece and how it fits together. Zooms can be pretty complicated though, and if you really want this lens to work

again you might want to get it serviced by someone with experience.

 

<P><A HREF=http://forums.dpreview.com/forums/readflat.asp?forum=1036&message=19236004&q=dismantle&qf=m>This isn't

a quick-shift lens</A> but it might give you some sense of what you might be getting into.

[joe_jackson4]

Bearing in mind that I've seen the 18-55 here for 50 euros brand new, I think I'd just buy a new one if it seems like something's gone wrong with it... Hardly seems worth messing about with such a cheap lens, TBH.

 

And hey, if it still focuses and takes good pics, don't worry about it... :)

[miserere_mei]

Paul, you're too pragmatic for this forum. Are you an engineer, by any chance? :-)

[alan_chan4]

The QS mechanism sits right where the AF slot is. Sometimes when the AF stops, the mechanism might not fully disengage and MF feels a little rough. Just AF it again usually frees it up.