Originally posted by c.a.m Well done on venturing into the inside of the camera. That's a task not for the faint of heart.
The absence of the retainer is disconcerting. It would probably have been a small c-clip (circlip). What's your theory? Missed during assembly? Plastic, and fractured into several pieces? A design flaw (I'd guess not)?
Anyways, congratulations on a fine job.
- Craig
Thanks Craig. The retainer is a circlip indeed. Could have been a plastic one that broke. I made my own metal circlip this time by cutting a piece out of a normal round washer, but you would have to have the exact right size lying around. Did I mention it is really tiny? (inside diameter around 1.5mm) Also, the outside diameter can't be very large either as it has to fit into a recession in the front cover. To get the homemade circlip right I gently squeezed it with pliers until it fit tight around the button shaft recession. Best option is to order it beforehand as I should have done. Just don't assume a circlip will be waiting for you at the bottom of your camera as I did.
I will try and describe the disassembly involved.
You need to remove the bottom plate. There's ten screws holding it (two underneath the battery cover). Please keep track of all the screws and which holes they belong. You'll need to devise a system for this. Maybe even tape them to a piece of paper in the correct order. Work on a clean desk in a systematic fashion and have the time to work on it with good lighting.
If you're insecure of your own mechanical abilities involving an expensive piece of photographic equipment, don't even start. You can still stop here and reassemble if the task looks daunting.
Remove the battery and remove the screw at the bottom of the battery compartment. Remove the screws on the sides of the camera. Remove the two screws underneath the flash. Remove the eyecup and the two screws underneath that.
The one that took me a long time to find is the screw underneath the left rubber grip on the front of the camera (a bit under where it says K-5). Peel the rubber grip from the top until you see the screw. Remove it. You'll probably need some new double-sided tape to re-attach the rubber afterwards.
Remove the screws holding the metal lens mount to the camera. Remove it.
Now you can gently lift up the top cover. It doesn't need to go all the way off. The goal is to remove the front cover. You'll need to open the sides a bit with a plastic opening tool/guitar pick. The external flash socket is attached to the top with wires. If you remove a screw on the back of that you can take it out and remove the whole front.
Look carefully at how the system works. The lens securing pin assembly will probably come off. Attach the rubber to the release button shaft. Stick it in the front cover and push it all the way down. You'll be able to attach the circlip from the back. This prevents the button from falling out.
Reattach everything and screw it back down. Make sure the release button works as it should. Now just do everything in the reverse order. Best to use a Giottos air blower or similar in between and afterwards to get out any dust from the parts and the inside of the camera.