Apple FileWare

FileWare floppy disk drives and diskettes were designed by Apple Computer as a higher-performance alternative to the Disk II and Disk III floppy systems used on the Apple II and Apple III personal computers. The drives were also referred to as Apple 871 drives in service documentation, based on their approximate formatted storage capacity in kilobytes, but were most commonly known by their code name, Twiggy, after a 1960s fashion model (Twiggy) who was famously thin.

In 1978, Apple intended to develop its own FileWare drive mechanism for use in the new Apple /// and Apple Lisa business computers being developed. They quickly ran into difficulties which precluded them from being incorporated in the Apple ///, which continued to use the earlier Shugart design. Finally, FileWare drives were implemented in the Lisa computer, released on January 19, 1983. The original Macintosh computer was originally intended to implement a Shugart drive, then later, a FileWare drive, before eventually shipping with Sony's 3.5" 400k diskette drive. Although Apple planned to make FileWare drives available for the Apple II and Apple III, and announced them under the names UniFile and DuoFile (for single and dual drives, respectively), these products were never shipped.

FileWare drives are 5¼-inch double-sided, but are not mechanically compatible with industry-standard diskettes. In a single-sided floppy disk drive, the disk head is opposed by a foam pressure pad. In a normal double-sided floppy disk drive, the top and bottom heads are almost directly opposed to each other. Apple was concerned about head wear, and instead designed the FileWare drive such that the top and bottom heads are on opposite sides of the spindle, and each is opposed by a pressure pad. Since there is only one actuator to move the heads, when one head is near the spindle, the other is near the outer rim of the disk.

The drive is approximately the same size as a standard full-height 5¼ inch floppy drive, but does not use the standard mounting hole locations. The electrical interface is completely different from that of standard drives, though conceptually similar to that of the Disk II.

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