steve@hite386.UUCP (Steve Hite) (05/24/90)
What I do to make the hole is not to drill but to use a soldering iron. The plastic melts and you get a perfect seal. There will be some excess plastic that "dries" up around the hole but just take a hobby knife and shave it smooth. If you don't then it can wind up getting stuck in your floppy drive but more times then not it'll get it jammed before it *pops* into position. What I do is get about 50 of the $0.49 800K floppies from MEI Micro (or have they gone down more since I checked 5 months ago?) and go to town with the soldering iron. I first format them with the Mac and if they pass use them there. If there are some bad sectors then I format them for use with my DOS machine and DOS will, of course, mark the bad sectors and I still have a very usable disk for my 386 Clone. I have had problems formatting these "solderized HD" disks for DOS under Apple File Exchange. The disk will format fine and I'll take it over to the 386 clone and sometimes I'll get bad sectors showing up. When I format that same disk under DOS, sure enough, the DOS format marks some sectors as bad that AFE didn't detect. Your mileage may very, though. For me, anyway, it's worth the "risk" vs. price because most of the stuff I backup is replaceable from info-mac or a friend I got the shareware, pdware, etc. from in the first place. I always keep copies of things I write of impor- tance in about 3 different locations so it's not a major issue. In a company environment, though, I would use nothing but "pure" 800K and 1.4 meg floppies just for the extra insurance (and besides, I'm doing their work and they're paying for the expensive floppies, not me). ------------------------------------- Steve Hite ...gatech!uflorida!unf7!hite386!steve
Lou@cup.portal.com (William Joseph Marriott) (05/29/90)
Boy, this is really depressing, the amount of misinformation about these drives and disks. Especially since many of the posters seems to be the kind of folks novice users look to for advice. Well, here's some honest facts and prudent rules: 1. Single-sided diskettes should be formatted at single-sided. Double-sided diskettes should be formatted as double-sided. High-Density disks should be formatted at high density. Mac disks should be formatted on a Mac. PC disks should be formatted on a PC, or on an FDHD Mac running Apple File Exchange. 2. Never mutilate a disk you intend to later use. Mutilation includes, but is not limited to: drilling, soldering, bending, cracking, prying, polishing, immersing, flipping, and melting disks. 3. You can use tape and certain kinds of hardware to format a high-density disk as 800K or 400K. Even if this operation seems to work, the disk will behave unreliably, and will ruined for high-density use. To put things in English terms, imagine diskettes are like multi-lane highways, and that your data is represented by different colored cars. An 800K disk has wide lanes and large cars, so fewer cars can fit on the highway at any time. An HD disk has very narrow lanes and tiny cars. Now,if you try to format an HD disk as 800K, you wind up putting wide cars on narrow lanes. The effect is that it is not always clear which lane a given car is in. Imagine the traffic problems that would ensue if no matter what you did, you would always have part of you car in someone else's lane. Imagine how flaky your disk will behave if you format it for a different density. 4. The magnetic field holding together data on an HD disk is weaker, and thus more susceptible to the things all disks are susceptible to. Under the rigors of typical college life, an 800K didk is probably more reliable.
mwilkins@jarthur.Claremont.EDU (Mark Wilkins) (05/29/90)
In article <30281@cup.portal.com> Lou@cup.portal.com (William Joseph Marriott) writes: >1. Single-sided diskettes should be formatted at single-sided. Double-sided >diskettes should be formatted as double-sided. High-Density disks should be >formatted at high density. Mac disks should be formatted on a Mac. PC disks >should be formatted on a PC, or on an FDHD Mac running Apple File Exchange. [stuff deleted] > >3. You can use tape and certain kinds of hardware to format a high-density >disk as 800K or 400K. Even if this operation seems to work, the disk will >behave unreliably, and will ruined for high-density use. To put things in >English terms, imagine diskettes are like multi-lane highways, and that >your data is represented by different colored cars. An 800K disk has wide >lanes and large cars, so fewer cars can fit on the highway at any time. An >HD disk has very narrow lanes and tiny cars. Now,if you try to format an >HD disk as 800K, you wind up putting wide cars on narrow lanes. The effect is >that it is not always clear which lane a given car is in. Imagine the traffic >problems that would ensue if no matter what you did, you would always have >part of you car in someone else's lane. Imagine how flaky your disk will >behave if you format it for a different density. Alright, two questions. 1) If formatting a DS/DD disk is so dangerous at high density, why don't ANY of the drives in the PC clone world check for the presence or absence of the hole used to indicate them? 2) Given (1), why is it that there have been no similar discussions of disk failure in the PC clone world, even among people who routinely buy DS/DD disks and format them at 1.4MB just because they've never been told any differently? Note that the Apple 1.4 MB low-level encoding scheme is identical to that of an IBM PC floppy, but the hardware is much different. If there is an answer to (2), it probably has to do with that. I agree with your statement 2 that mutilating a disk is a recipe for disaster. However, nobody who advocates Apple's party line has ever given me an answer to these two objections. By the way, if you have any references to publicly available articles in engineering journals or the like which support Apple's official statements on the matter, I'm curious. -- Mark Wilkins
cs223101@umbc5.umbc.edu (CMSC 223/01011) (05/29/90)
To make a slight addendum to your statements, here's a question that's been bothering me for years. When a company sells a single-sided 5.25 disk, that means it's warrented to be free of defects on one side only. My problem is that Apple 5.25 drives format the *back* of a disk, while Commodore and Atari drives format the *front*. Which side is certified?!? I understand that flipping a disk moves all the dirt back across the head, but that's not quite the same thing as formatting the back of a disk. [RICH]
gaynor@armadillo.cis.ohio-state.edu (Jim Gaynor) (05/29/90)
In article <7309@jarthur.Claremont.EDU> mwilkins@jarthur.Claremont.EDU (Mark Wilkins) writes: > Alright, two questions. > > 1) If formatting a DS/DD disk is so dangerous at high density, why don't >ANY of the drives in the PC clone world check for the presence or absence of >the hole used to indicate them? You are wrong. The old, "original" standard for HD disks and drives made no distinction between DS/DD and HD diskettes. The current standard has HD disks with the "HD" printed on the diskette, and the extra hole. IBM PS/2 machines, and some other clones use drives that were built by the old standard, and do not detect for the extra hole (and therefore do not check for HD disks, and will format DS/DD as HD) Note that these drives, since they lack the extra detection mechanism, are cheaper. Zenith PCs, and some of the other "high-end" clones, do use the drives which check for HD disks, and therefore will refuse to format a DS/DD diskette as a HD diskette. > 2) Given (1), why is it that there have been no similar discussions of disk >failure in the PC clone world, even among people who routinely buy DS/DD >disks and format them at 1.4MB just because they've never been told any >differently? Well, (1) is no longer a given. There are two reasons for (2): A) The DOS formatting scheme marks off bad sectors. Thus, an DS/DD diskette formatted as HD may (and most times will) have bad sectors, but will still be usable. B) Disks going "bad" for various reasons seems to be much more "accepted" in the MS-DOS world than on the Mac side. (This is only opinion here). Note the proliferation of programs such as Norton Utils, PC Tools, and Mace, whereas equivalents in the Mac world are not as widespread, and are only recently becoming high-sellers. > Note that the Apple 1.4 MB low-level encoding scheme is identical to that >of an IBM PC floppy, but the hardware is much different. If there is an >answer to (2), it probably has to do with that. Yes, the hardware is different between an IBM drive and an Apple drive - see my reply to (1). I believe, however, that Zenith and Apple use the same drive mechanism (but different controllers). But this may be false. > I agree with your statement 2 that mutilating a disk is a recipe for >disaster. However, nobody who advocates Apple's party line has ever >given me an answer to these two objections. There, my friend, are your answers. > By the way, if you have any references to publicly available articles in >engineering journals or the like which support Apple's official statements >on the matter, I'm curious. Do you have access to similar materials supporting your claims of "no difference" between types of diskettes? I, at least, have the support of diskette manufacturers, floppy drive manufacturers, and the producers of both Macintosh and MS-DOS computers. >-- Mark Wilkins -=- +-----------------------------------------------------------------------------+ | Jim Gaynor - Graduating Macintosh Consultant - The Ohio State Univ. IRCC | | Email at [gaynor@cis.ohio.state.edu] or [gaynor@osu-20.ircc.ohio-state.edu] | |_ "You, yes YOU, want to hire me! Send away for my amazing resume TODAY!" _|
ac08@vaxb.acs.unt.edu (05/29/90)
In article <3082@husc6.harvard.edu>, wichers@husc7.HARVARD.EDU (John Wichers) writes: > In article <30281@cup.portal.com> Lou@cup.portal.com > (William Joseph Marriott) writes: >>1. Single-sided diskettes should be formatted at single-sided. Double-sided >>diskettes should be formatted as double-sided. High-Density disks should be >>formatted at high density. Mac disks should be formatted on a Mac. PC disks >>should be formatted on a PC, or on an FDHD Mac running Apple File Exchange. > The only difference between single sided disks and double sided disks is that > only one side is verified for the single sided disks. I have been formatting > SS/DD disks as DS for a number of years now, and I haven't had any > more problems with those disks than with the DS/DD disks I have. Sure, > sometimes a SS/DD disk can't be formatted as DS, but in those instances I > just reformat them as SS. No problem. > You mean there's stores there that still sell SSDD disks? I haven't seen any here since Target stopped selling them- they were more expensive than the DSDD ones... With DSDD Sony 3.5" disks going for $7.95/box of10 at Soft Warehouse, I'd rather just go for the quality, thankyouverymuch... C Irby ac08@vaxb.acs.unt.edu ac08@untvax "System 7.0 was going to have protected memory, but they lost the disks with the source code..."
wichers@husc7.HARVARD.EDU (John Wichers) (05/30/90)
In article <30281@cup.portal.com> Lou@cup.portal.com (William Joseph Marriott) writes: >1. Single-sided diskettes should be formatted at single-sided. Double-sided >diskettes should be formatted as double-sided. High-Density disks should be >formatted at high density. Mac disks should be formatted on a Mac. PC disks >should be formatted on a PC, or on an FDHD Mac running Apple File Exchange. I love people who blindly follow the party line. The only difference between single sided disks and double sided disks is that only one side is verified for the single sided disks. I have been formatting SS/DD disks as DS for a number of years now, and I haven't had any more problems with those disks than with the DS/DD disks I have. Sure, sometimes a SS/DD disk can't be formatted as DS, but in those instances I just reformat them as SS. No problem. As I've only got a vanilla SE, I haven't had to deal with HD disks enough to be able to argue for one side or another in the current debate. --jjw __ Hail to the sungod. || John Wichers || wichers@husc4.harvard.edu He sure is a fun god. || 121 Museum St #2, Somerville Ma. 02143 Ra! Ra! Ra! || Anarchy - It's not a law, it's just a good idea. || Jesus saves sinners ... and redeems them for valuable cash prizes!!! ||
kassover@jupiter.crd.ge.com (David Kassover) (05/30/90)
In article <34@hite386.UUCP> steve@hite386.UUCP (Steve Hite) writes: > > What I do to make the hole is not to drill but to use a soldering iron. >The plastic melts and you get a perfect seal. ... > What I do is get about 50 of the $0.49 800K floppies from MEI Micro (or Uh, just curious: how long does it take you to process 50 floppies? How many out of the 50 are truly unuseable anywhere in your environment? What wattage is your soldering iron? How much did you pay for it? When? -- David Kassover "Proper technique helps protect you against kassover@ra.crd.ge.com sharp weapons and dull judges." kassover@crd.ge.com F. Collins
kassover@jupiter.crd.ge.com (David Kassover) (05/30/90)
In article <7309@jarthur.Claremont.EDU> mwilkins@jarthur.Claremont.EDU (Mark Wilkins) writes: ... > Alright, two questions. > > 1) If formatting a DS/DD disk is so dangerous at high density, why don't >ANY of the drives in the PC clone world check for the presence or absence of >the hole used to indicate them? > > 2) Given (1), why is it that there have been no similar discussions of disk >failure in the PC clone world, even among people who routinely buy DS/DD >disks and format them at 1.4MB just because they've never been told any >differently? Everyone has his own criteria for magnetic media performance. Many big service bureaus buy used tapes. When their error rate gets unacceptable, they throw them out (or use them for data transfer to places that are known for not returning media 8-) One place I know of spends a ridiculous (to me) amount of energy on finding sources of tape certified at 800 bpi. (it's cheaper that way, they say) I, on the other hand, want to minimize the chances of having a data error happen at all, let alone was it backed up. The reason for this is that the restore procedure is painful and emotionally stressing to my staff, and I'd rather not have it happen. No one stops you from running the cheapest fuel you can find in your car, either. On the other hand, eg, running out of fuel far away from a filling station because you're suddenly getting 3/4'ths your normal mileage isn't terribly much fun, IMHO. -- David Kassover "Proper technique helps protect you against kassover@ra.crd.ge.com sharp weapons and dull judges." kassover@crd.ge.com F. Collins
mwilkins@jarthur.Claremont.EDU (Mark Wilkins) (05/30/90)
In article <80967@tut.cis.ohio-state.edu> Jim Gaynor <gaynor@cis.ohio-state.edu> writes: >> By the way, if you have any references to publicly available articles in >>engineering journals or the like which support Apple's official statements >>on the matter, I'm curious. > > Do you have access to similar materials supporting your claims of >"no difference" between types of diskettes? I, at least, have the support >of diskette manufacturers, floppy drive manufacturers, and the producers of >both Macintosh and MS-DOS computers. I'm inclined to say you're right about all of this, especially because it wouldn't surprise me a bit if IBM were passing off second-rate disk drives in their PS/2 machines. However, the reason I asked this last question is not by way of a challenge, but rather to suggest that disk and disk-drive manufacturers would DEFINITELY have a motive for being unclear about this stuff, especially if the only difference between DS/DD and DS/HD disks were the price. Specifically, I'm wondering if there's anyone who has done extensive, controlled testing of this stuff other than those who manufacture the disks. Something on the order of a Consumer Reports article or something. Thanks for taking the time to respond to my comments. -- Mark Wilkins
derosa@motcid.UUCP (John DeRosa) (05/30/90)
One small piece of information. I have seen in various Macintosh Catalogs a device that very cleanly punches the HD square hole in a DSDD disk. Budgetbytes I believe. Also, someone made a comparison about traffic lanes and wide cars. I think that the analogy is wrong. The media (i.e. iron-oxide particles on a plastic plater) in the disk is homogeneous (i.e. the iron-oxide particles are not layed down in "lanes" but are completely uniform across the plater). Actually, iron- oxide is too simple of a term, most magnetic media is formed with a "soup" of ingredients including other ferris- oxides and rare earths (thus the different settings on your tape player for tape bias). For the purposes of this discussion, we will use iron-oxide. (historical note: the first tape recorders used a steel wire and were called "wire recorders. How's that for basic magnetics?). The formatting process is what causes the "lanes" to be created on the disk. This is not a physical process (i.e. grooves are not dug into the iron-oxide) but an electrical process whereby the random magnetic ordering of the iron-oxide is changed into constant magnetic "lanes". Therefore formatting a DSDD disk as HD just creates different magnetic "lanes", smaller and closer together in the case of HD formatting. There in lies the problem. DSDD disks use a different "grade" of iron-oxide that HD disks. HD disks (because the magnetic lanes are closer together) uses a finer and better quality of iron-oxide in the manufacturing process. Also the HD drives use a lower magnetic field in the read/write head to prevent problems between adjacent "lanes". BUT....who is to say that the manufacturers are not just producing one type of (higher grade) disk and putting SSDD, DSDD or HD on the outside casing? This would save them money in the long run. Therefore you could format DSDD as HD and live happily ever after. Isn't circular logic wonderful? =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= = John DeRosa, Motorola, Inc, Cellular Infrastructure Division = = e-mail: ...uunet!motcid!derosaj = = Applelink: N1111 = = I do not hold by employer responsible for any information in this message = = nor am I responsible for anything my employer may do or say. = =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
buckley@sumex-aim.stanford.edu (Margret Buckley) (06/01/90)
A hole punch works perfectly to trick a FDHD drive into thinking your DD disk is really HD. Margret Buckley SUMEX Computer Project Knowledge Systems Laboratory Stanford University