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Also it's possible to get at the floppy just by removing the four screws on the back and pulling the back case, but the header for the floppy is directly under a cutout in the frame, and surrounded by a few caps, so it might be easy to slice your fingers on the frame metal. By dropping the pan and logic boardyou have much better access to the cable end without sharp metal around it.
You can see it, just to the right of the head. There seems to be a bit of excess lubricant right on the end of the rod, but it's interesting to see that rod is not secured at that end in any way.
Nearest the top of the picture, just below the three caps, with the shiny screw, and seems to share mounting with the optical interrupter for track 0. Here's a slightly out of focus view from the back of the drive, showing the angle, and how it overlaps the double L shaped piece of identical material:
So, Is that the tab that breaks and lets the guide rod shift? If so, what is the goal of the application of epoxy? Are we trying to fix the rod in place? Or trying to reinforce that plastic tab? Am I trying to loosen that tab, apply epoxy in the gap formed by the tilt and overlap and retighten? Epoxy across the top of the two nylon parts effectively tying them together into one piece and reinforcing the top part? All of the above? It looks like there is just enough room to do this while allowing full travel of the head along the rod. This is very slippery nylon like plastic and typically epoxy does not bond well to stuff like this. I can use a scalpel and micro file to roughen the surfaces to hopefully give the epoxy more grip. I agree with the others who think this assembly stinks. I would so much rather have metal circular retainers on BOTH ends of the rod, secured to the frame by screws.
Please let me know if I've identified the correct part (there's no visible evidence of a crack yet), and provide any input you have with regard to what to epoxy, etc...
Or this, at the back end of the guide rod:
It seems from the previous threads that folks are talking about the one in the second photo, at the back of the guide rod. But in the 2017 thread, "New Cat Repairs" by Marcin Wichary it seems that the tab at the back end is fine, but the tab in the middle of the guide rod is what snapped.
Thanks for any and all advice and details....
Both have shiny screws going through them.
I used industrial CA as a bonding agent to secure the nylon tab to the metal frame they rest on, and some more on the top of the tabs to laminate them to the aluminum straps. The aluminum stock was think enough so that I could use the existing crews to secure them
Here they are installed:
The straps don't interfere with the drive head assembly or any other mechanisms, and clear the guide rod completely.
I've tested the drive with two separate floppies. All good so far (knock wood).
With the straps in place, I am considering a bead of epoxy across the top to provide extra mass and further rigidity to the reinforced tabs.
To finish out the disassembly steps:
16 - Release the spring wires from the left and right sides of the drive.
17 - Remove the large spring from the top of the drive
18 - jiggle the top tray forward and back a bit, trying to clear the black plastic catches and arms.
19 - remove screw and the black plastic block on the right, near the black hook shaped part and the pivot for the metal arm (where you removed the large spring). Note that the block is mounted both insde and outside the frame of the drive. It will need to go back exactly the same way.
20 - jiggle the top tray forward and back a bit, the pins on the sides need to come out of the slots, at the time that the central U shaped "fork" needs to slide out of the drive head assembly.
21 - Repair or reinforce the plastic tabs securing the guide rod as you see fit.
Reassembly is the reverse of the first 20 steps.
Thanks all. Hope this description shows up in Google for the next person who needs to repair or protect their Cat.