So first a little back story on why I had to fix my Canon EFS 18-55mm lens. Some time ago when Virtuabotix.com was little more than an idea and I had first started taking photos of products for Amazon my wife and I both reached for my Canon at the same time… and much to my dismay the camera found itself in neither of our hands.
I watched in horror as my beautiful (expensive) Canon SLR fell as if in slow motion to it’s all but certain doom. There was a snap that was shortly followed by a thud that made me sick inside, and after the shock had worn off I discovered much to my relief that the camera itself had suffered no damage. The lens however (though it appeared perfectly fine) was not so lucky.
It rattled when you shook it, and the Automatic focus had completely stopped working. You would think that this is where that story would have ended, and the next begun, but actually I have continued to use that lens with manual focus only for about two years now until yesterday.
First of all let me say ahead of time that more than anything I was able to diagnose some problems, and god only knows if I permanently fixed the stuff. Either way I wanted to share some sexy pictures of the lenses guts so that Orion will be happy (Orion is my photographer, and web designer for Virtuabotix.com), so you can look at them too.
So until Orion suggested I take photos the process is a little undocumented, but as you can see there are 3 control wire groups that go into the PCB that mounts over this opening when you first take the bottom lens cover off.
When you go to take the lens cover off don’t forget there are usually at least two super tiny screws that go into the side of the electronic contacts that control the lens, so be sure to take them off and put them somewhere safe.
The metal enclosure int he top is the gearbox that most of the work I did focused on. Also after all was said and done the most likely culprit appears to be a piece of plastic that fell off right next to the blurry silver metal stopper in the middle left reassesses of the lens. From what I can tell the piece of plastic was keeping continuous pressure on the gear, which was making it skip and lock up.
Now, though I couldn’t replace the piece of plastic in the bottom I did notice that the gear on the leftmost side had lost it’s tiny plastic peg, and that it moved a little too freely, which seemed to add to the gumming up for no reason problem.
I lubricated the gears, and then used soldering tweazers to melt a small 100 mil (spacing) vertical pin through the very center of the gear. That turned out to be exactly the right size to keep the gear lined up in the gearbox.
After that I put the gearbox back together and bent the plastic slightly inward for the lower gear wall which the dowel that comes out of the base of that gear we just melted and stabbed with a pin from a random PCB. Then I put everything back together and prayed.
Now the lens didn’t come whirring back to life exactly, it still refuses to pick a focal point when the point is too far away, but now all I have to do is get the camera into the ballpark and the autofocus is more then happy to kick in. So that’s at least progress.
Thanks for reading, and have a great day! Don’t forget to check out my other articles, and have a look at Virtuabotix.com if you like robotics and other nerdy stuff.