Repairing a Canon 50mm FD F1.4 lens is not that hard if you have the proper tools. This how to repair a Canon lens video will walk you thorough the steps to get your vintage lens disassembled, cleaned, and reassembled.
Cleaning the aperture blades is the hardest part and should be done slowly and with a lot of care. The rest comes down to doing your best not to damage the lens elements during the disassembly process.
I would like to thank Tuber mikeno62 for his very detailed tear-down video.
Some of the tools needed for the breakdown of the Canon 50mm FD F1.4 lens is – jewelers screwdriver set, cotton swabs, Isopropyl alcohol or nail polish remover as cleaning fluid, micro fiber cloths for wiping down the lens elements, camera lens spanner tool, and a hard, well lit working surface.