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Buy 400k and 800k disks
- Thread starter Ih8reno
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You can often find 800k disks on eBay in various formats. 400k disks are harder to come by however. And yes, your 6500 will write 800K disks just fine. Using disk copy 4.2 it can also write 400k MFS images even up to Mac OS 9.2.2. I assume your 6500 is running Mac OS 7.X. That has semi 400k support built in. System 6 and before have full.
Well resuemyclassicmac is a great site alright, but 800k disks are easy to find in packs of 10 or 20 even here in Ireland. It's just great to have the freedom to write you're own. Is your 512K an original or a 512Ke? It definitely has a 400k I mean? 400k image can only be written blind in os 9. You can mount them. I use my pm8600/250 running Mac OS 9.2.2 to write 800k disks for my 512Ke. I also run an appleshare server from my 8600 and access it on my 512Ke. I highly recommend this, it gives the 512K much more flexibility. Just get two localtalk adapters and use the workstation installer disk 1.1 for the 512K.
Well you can boot from an external drive. I boot my 512Ke from external usually myself. You'll want 800k disks for bigger games and later operating software. 800k disks hold more of course but are also much easier to manage. They are fully supported by the more modern OS 9.2.2 and disk copy 6.3.
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I think 800k disks can also be formatted to 400k by selecting "single sided" during initialisation so they are again more useful.
What do you mean by "regular?" You should not use HD media for 800k or 400k disks. There are those that have had success with it, but far more have not. It essentially depends on your specific drive if it will work or not. If you get DD media, you can use that as either 400 or 800k; as tevion5 says, it's just down to single- or double-sided formatting, which is decided by your OS.
Short form:
Single-sided (400K) and double-sided (800K) disks use the same magnetic media inside the disk. On the very oldest single-sided disks, it may have only been usable on one side, but by the time double-sided disks had taken over, most media, even that sold as single-sided, was actually double-sided. Thus, you can format any 800K disk as single-sided just fine.
Note that on SOME single-sided drives, the pad that touches the "back" of the disk may have deteriorated far enough by now that if you use an 800K disk in a 400K drive long enough, that disk might not be able to be used an an 800K disk again. (The "back" side of the disk material might have enough wear from the broken-down pad on the drive that it is physically scratched.)
High-Density (1.4 MB) disks, on the other hand, use a different magnetic media than the older 400K and 800K disks. It is possible to reformat an HD disk as an 800K or 400K disk (or vice versa,) but it is not a good idea. The differences in magnetic coatings make it very unreliable. And once you use a disk in the "wrong" format, it becomes unreliable even if you reformat it back to its original format.
I've done this when I had to move a file and didn't have an 800K disk available, but I made sure not to use that floppy disk again.
Single-sided (400K) and double-sided (800K) disks use the same magnetic media inside the disk. On the very oldest single-sided disks, it may have only been usable on one side, but by the time double-sided disks had taken over, most media, even that sold as single-sided, was actually double-sided. Thus, you can format any 800K disk as single-sided just fine.
Note that on SOME single-sided drives, the pad that touches the "back" of the disk may have deteriorated far enough by now that if you use an 800K disk in a 400K drive long enough, that disk might not be able to be used an an 800K disk again. (The "back" side of the disk material might have enough wear from the broken-down pad on the drive that it is physically scratched.)
High-Density (1.4 MB) disks, on the other hand, use a different magnetic media than the older 400K and 800K disks. It is possible to reformat an HD disk as an 800K or 400K disk (or vice versa,) but it is not a good idea. The differences in magnetic coatings make it very unreliable. And once you use a disk in the "wrong" format, it becomes unreliable even if you reformat it back to its original format.
I've done this when I had to move a file and didn't have an 800K disk available, but I made sure not to use that floppy disk again.
I did an experiment using HD disks as DD with the tape over the window a few years ago. I filled up the disks with files, tested them and left them. I tried them again recently and they're still fine. It's been 3 years now. The disks were nothing special, just regular Imation HD diskettes.
Writing once and letting them sit probably won't have a problem - but regularly reading/writing/erasing/re-writing will likely shorten their lifespan considerably.