If you can initialize a floppy disk, write to it it and then read from it all on the same Mac (Classic), the mechanism is all right. If that same floppy disk cannot be read in the FDD of another Mac (Colour Classic), it is probable that the alignment of the floppy drive that made the diskette is faulty. Terminal.
If a floppy disk made on another Mac (CC) cannot be recognized as one by the FDD of the Mac in question (Classic), and you do not suspect the drive of the other Mac, you may have either a dirty drive to
clean or a dead drive to replace. Similarly if you get read errors, as long as you are sure of the goodness of the floppy disk.
You don't need 19 floppies to install System 7.5.3 (and another few for the update to 7.5.5, which is overkill for a RAM-starved Classic). What you need is one folder on the desktop of the Classic with the 19 files (one .img and 18 parts) together in that folder. This you can achieve with one floppy disk and a working drive. My own opinion is that 7.5 is as far as you can comfortably go with only 4MB of RAM max. and 8MHz.
However, he who has ethernet has no need for floppies. The G5 and the CC can talk via a crossover ethernet cable, even if the G5 is running Tiger. Make Tiger the server, and talk over TCP/IP. Make the floppies on the CC, if you can, and if the Classic can read them, that will work. With a LocalTalk/SCSI adapter, or better, an EN/SC adapter (ethernet to SCSI), the Classic can talk dirty over ethernet to the CC, and thereby avoid the intervention of floppies into the cosy relationship. Lastly, given the scarcity of something/SCSI adapters, the Classic and CC can exchange files directly over LocalTalk through their serial ports. Much cheaper, but slower than ethernet. But it will be far in advance of anything that you can achieve by banging your head on a wall over floppy drives.
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