Post by casualcollector on Mar 1, 2013 20:38:22 GMT -5
Picked up one of these attached to an old EOS Rebel film body several weeks ago. Seems the lens did a face plant while attached to the camera and focus no workie! Found excellent instructions and video of disassembly via Google and You Tube. Upon following the tutorial I found the focus ring pegs that engage a slot in the optical block were both broken off by the force of the fall. The focus ring turned but the lens wasn't being driven back and forth.
nis-lab.is.s.u-tokyo.ac.jp/~ybando/rgb_filter/disassembly.pdf
I was able to re-attach the pegs using two part epoxy. Excess epoxy had to be trimmed and filed off so the focus ring would turn smoothly within the body of the lens. Getting the lens back together correctly was the tricky part. There are two thin metal rings that look very much alike that hold the repaired assembly in the body. Both are the same diameter and have notches for a one way only fit inside the lens body. Look at them closely and you'll see one is thicker and the other has slightly longer notches on the outside diameter.
This is the part that fooled me at first. Since the thicker of the two came out last, it went back in first. I stacked the second ring atop it then installed the electronic/optic assembly. The assembly promptly came back out of the barrel... After several more attempts it was clear these two ring locked the assembly into the barrel, but how? What I missed involved the thicker ring. Install it first then turn it clockwise a few degrees until it locks in under the locating lugs in the housing. Place the second ring atop the first and slide the optical assembly into the barrel and rotate the focus ring slightly counter-clockwise (anti-clockwise for those who speak the Queen's English). Lugs on the focus ring will lock in behind the thick ring and hold everything together. Continue reassembly per the instructions.
I now have a working "Nifty Fifty" for my EOS DSLR.
nis-lab.is.s.u-tokyo.ac.jp/~ybando/rgb_filter/disassembly.pdf
I was able to re-attach the pegs using two part epoxy. Excess epoxy had to be trimmed and filed off so the focus ring would turn smoothly within the body of the lens. Getting the lens back together correctly was the tricky part. There are two thin metal rings that look very much alike that hold the repaired assembly in the body. Both are the same diameter and have notches for a one way only fit inside the lens body. Look at them closely and you'll see one is thicker and the other has slightly longer notches on the outside diameter.
This is the part that fooled me at first. Since the thicker of the two came out last, it went back in first. I stacked the second ring atop it then installed the electronic/optic assembly. The assembly promptly came back out of the barrel... After several more attempts it was clear these two ring locked the assembly into the barrel, but how? What I missed involved the thicker ring. Install it first then turn it clockwise a few degrees until it locks in under the locating lugs in the housing. Place the second ring atop the first and slide the optical assembly into the barrel and rotate the focus ring slightly counter-clockwise (anti-clockwise for those who speak the Queen's English). Lugs on the focus ring will lock in behind the thick ring and hold everything together. Continue reassembly per the instructions.
I now have a working "Nifty Fifty" for my EOS DSLR.