A couple years ago, my first 16-45 took a tumble off a low table onto a carpeted floor. Something broke inside and the zoom and focus were jammed and wouldn't turn all the way. I bought another one second-hand to replace it and stuck it on a shelf to collect dust.
I took it off the shelf yesterday out of boredom to see if I could figure out how it works. I managed to find the culprit, a piece of the focusing helicoil snapped off when it fell and was jamming the camways. I just now managed to get it back together,but I managed to break it in a different way. I stretched the spring that closes the aperture, so it doesn't return closed when tension is removed. Should be a simple repair if I decide to bother replacing the spring. It has some funky behavior besides that, if I turn the focus ring to infinity, it locks in place and won't move. I have to tip the lens downward for it to allow the focus ring to turn again. Coinciding with that, there is about an 1/8 inch of movement in the front element assembly (which is what the focusing helicoil actually moves to focus the lens). It was finicky getting it back together since things have to line up just so, and it takes some fiddling to get them aligned right. One thing to note, if you ever take one apart, there are shims in the back that pop out if you don't realize they are there. I'm sure they are wrong now since I wasn't expecting to have them fall out. The data pins are wicked finicky to insert and align as well. I picked individual pins off the floor more than once. I put it back together well enough that the camera recognized the lens and it focuses (seems sharp enough in the viewfinder). If you have a junk lens that you don't mind trashing, it's worth it just to see how it works. I've taken apart a 50mm prime and this lens wasn't that much more complicated. -- My Year38 365 project http://year38.blogspot.com/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
