Dusty Disks by DB Moore 43 !¡ 43 !¡ 43 !¡ 43 !¡ 43 !¡ 43 !¡ 43 !¡ 43 It seems, in these modern times, that when a manufacturer runs some sort of 'advertising campaign', or makes a statement about the suitability or 'worthiness' of their product, we the general public, are fed all sorts of rubbish. This 'rubbish' can take many forms...from straight-out misleading lies, to equally misleading truthful statements! One of my favourites, is the marketing statements made by just about every supplier and/or manufacturer of computer 'floppy disk media'...both sizes. 'Certified Error Free' is a good truthful one, sounds really impressive too. All this means, is that anyone who's involved with making disks these days, has got themselves a plant/machine that can turn out disk after disk, with the sort of accuracy you'd expect after just over 10 years of practise with it! It also means the same equipment can reliably carry-out Quality Assurance checks on what it's making, and spit the 'duds' out with unerring compitence. I can't recall a single instance of having a brand new piece of media failing a format operation first up. How about anyone else? The really good one though, is the all too often seen 'lifetime guarantee', what a load of bollocks! First of all, you'd have to wonder about what a disk's 'lifetime' actually is? I see some prudent manufacturers quoting things like 'can take over 30-million passes of the read/write heads'..etc. etc. I'm sure everyone's keeping count!? I'm equally sure the manufacturers have some kind of 'gizmo' to tell them *exactly* how many passes the particular disk has been subjected to?? Sure....as if!!! Let's face it, 90% of all floppy-disk failures are caused by some tiny speck of debris getting caught between the case-liner and the spinning disk-film, which leaves that wonderful tell-tale scratch which is clearly visible if you have a look. [Which is exactly what the dealer you took your floppy back to is going to look for, and if a scratch is spotted, it'll be deemed *your* fault.....sorry, no refund!] For the other 10% of failures, some may even be attributed to some kind of manufacturing fault [a real 'hard to prove'], and I suppose other the most significant problems, are usually related to the actual disk-drive itself....from just plain filthy heads, to the heads digging into the disk's media..[because someone didn't take enough care of their disks or drive ....or... whilst cleaning it themselves, they've bent the head-carrier/s. Common one this...bent or misaligned head-carriers. It's only a tiny slot...how do they get their hammer in there???] I might point out, that even if your dealer does concede that the disk is in someway faulty, and give you a replacement, that doesn't get any data that you may have lost back. 'Lifetime Guarantee'? Bah and fooshbah!! However, if you'd be in agreement about the little specks of [??] something as being your prime cause of woe with floppy failures, do you ever wonder about how those offending specks get in there in the first place? [Actually, here's a good place to mention that in my experience, 5.25" disks have caused me more strife than 3.25" disks in this respect, and I always put this down to the fact that 5.25" disks don't have the little sliding 'door' over the window. Doesn't matter how many warnings you post, that open 'window' is 'vulnerability intrinsic'.] Anyway, if you've been inside a disk-drive or two [by ten-to-the-third, in my case!], it's absolutely amazing, [is it not?], just how much rubbish seems to pile up right next to the heads. This is a grand spot for it too! Jerking back and forth at whim of the stepper, just waiting to be shaken from it's precarious perch...straight down onto the disk surface....snik-snik-snik-snik, uh-oh!!! In A500s [and machines of similar design], reckoning reasoned this build-up to be due to a> the size and shape of the disk-slot, complete with the bottom ledge of the opening, which is a great little 'landing pad' for all the stuff floating about in the air, [also gives the little cockroaches somethin' to hang onto when they climb in], and b> the shear number of disks that go in and out of the drive. How those bits of rubbish carried into the drive on the disk-case managed to all put themselves adjacent to the heads, is probably something to do with 'static attraction', or something like that!! [huh?] That's a bit of horrible 'voodoo'...static charges and the like..., but I suppose it's at least as reasonable as any other idea! One thing that I did find out about machines of a more 'normal' construction, [you know, everything in a big case, with the power-supply and it's fan at the back inside the case as well], were the problems that fan actually contributes to! You tend not to think about these things, here too I'm guilty, but having worked with systems that were intended for 'industrial environments', I couldn't help but notice that in these types of machines, there's [most-times] a foam-filter on the induction-side of the cooling fan. This is, of cousre, to stop the fan sucking in all manner of rubbish and depositing it on the boards. Most 'domestic' machines, aren't so mindfully built. It's rare nowdays to see a 'negatively charged' case [with the power-supply's fan on the inside pushing air out through the vents], and this is probably because they realized that the fan was drawing it's air in through any opening it could...under the machine [real dusty spot this], or in through the disk-drive openings. 'Positively charged' cases are the most common, where the fan's at the back drawing in air [dust,lint,insects] and pushing it out through any opening it can, any guesses where? Most users are aware of the importance of 'area cleanliness' around their system, but for the number of setups I've seen [over a couple of hundred], this 'cleanliness' only extends out from the front of the machine....I know, because invariably I've been there to service/repair the unit, and have had to move the case to get at the back. More often than not, it's resembled the area one would usually find behind the 'fridge!! Think about it, how many cubic-litres of air do you consider goes through that fan in a month? I've had to scrape off build-ups of dust over 4mm thick, from the leading edges of cooling fans! I'm not going to bore you with the full accounts of what system-stuffups can be directly attributed to a deep-pile carpet of dust/lint being all over the innards, it'd frighten most folk! But next time you take to cleaning your area around your machine, think about these things and perhaps do a proper job of it. [move your case off the table, and clean there as well!] I got struck by this, trying to figure out why so many machines came in the w'shop, with the customers complaint reading 'keeps chewing disks' or 'diskdrive U/S'. Pull the drive apart, and it's chocker-block full of stuff like what you'd find in the vacuum-cleaner. Pull the power-supply apart...same story. If you get whacky enough, you can imagine that you see a path of dust leading from the PSU, across the board, around the inside corner of the case, up through the exposed innards of the diskdrive, and out through the disk-slot. If it's got a door on the drive.....well, it's a primitive filter, all the junk piles up around the cracks where the door doesn't seal correctly, just waiting for a disk to be put in. The door's flicked open by the disk, which throws the accumulation into the drive proper, and some on the disk as well, and then, snik-snik-snik...uh-oh! Once upon a time, you could buy foam-pads that were specifically designed to filter the air for cooling fans, [they didn't impede the air flow significantly], but I no longer know if this is the case. Hunting around some of the 'industrial' electronics suppliers may be fruitful, if you're so inclined. The more adventurous may like to rig up something home-made, but remember, it *must not* hinder that air-flow much [or it'll cook itself], and it will need to be cleaned from time to time. However, I doubt very much that fitting a filter is necessary, so long as you keep your area clean front *AND* back, but the exception would be those who do live in a really dusty or otherwise enviroment with lint and so-on floating about. [like, next door to a flour-mill] PSU-fans gobble anywhere between .3 and 3.0 cubic-meters of air *per minute*!! Multiply that by the number of minutes your system is running, take into account the average dust/lint particle count per cubic-meter of air, ....that's a *lot* of dust and stuff getting filtered by your case. Another thing I noted, was that cat-hair is particularly adept at infiltrating [ha ha] the case, but I reckon this might be because of their tails get whizzed by the fan, whilst they're chasing a cockroach that was feeding on a long forgotten piece of snackiepoos, lying mouldy behind the case!!!  Cheers! DBM 43 !¡ 43 !¡ 43 !¡ 43 !¡ 43 !¡ 43 !¡ 43 !¡ 43