So I'm curious
What's the normal trick for dustproofing a computer?
Welcome again to On-Call, our Friday feature in which fellow Reg readers share memories of jobs that went wrong. This week reader “DW” shares a tale that we hope isn't an April 1 joke, because he says the events below were reported to him by colleagues. He sent us his tale a while back, so hopefully we're not the butt of a …
I'd think that filters fitted in front of all openings in the casing (and in front of the fans) should normally do the trick. Of course, you're in for some filter maintenance then - and I'll wager that engineers are not too good at that either.
But at least the PC won't melt down so fast.
People sell sealed box, ip-rated, heat sink only no fans jobs for truly industrial applications. They cost a fortune and the spec isn't great, but they come with ip rated connectors for everything and can be configured with sensible cards for industrial applications (rs485 outputs or whatever).
To make them even more expensive you can have them certified for use on the railways and add GPS cards. They will however survive Armageddon (and have the option to be battery powered).
I'd think that filters fitted in front of all openings in the casing (and in front of the fans) should normally do the trick.
Problem is that in many (most?) PCs the fans are mounted to suck air out of the case, so the entry is via all the little cracks around CD drives, memory card slots, etc. Filtering input air there is almost impossible. I think you'd need to have a fan that pulled air into the box through an easily-changed filter, to have much hope of success.
If you have lots of standard PCs for office type work in a fixed location, it might be a good idea to set up a positive air pressure area that was fed from a filtered air supply. In the HVAC industry there are massive numbers of different fans, filters, etc that could be used for this purpose.
Then again, for simple use, it might be cheaper to regard the PC as a 'wear-out' consumable and have data stored on LAN drives that are well protected.
I dust proofed my tower years ago as I got annoyed with my GFX card being covered in dust and slowing down. You just need positive air pressure to stop the dust getting in through all the gaps, push more clean air into the tower than can get out easily. (Remember the breaking bad episode with the fly and Walter creates positive air pressure in the cooking room to make it into a clean room?)
The fan blowing air in should have a filter in front of it. I got mine on eBuyer I think for a couple of quid. Of course you need to clean the filter every so often, at home that's once a year, at a building site it'd probably be more frequent. A quick vacuum from the outside does the job, you could even tell the cleaner to do it, it's pretty fool proof.
" A quick vacuum from the outside does the job, you could even tell the cleaner to do it, it's pretty fool proof."
Except the cleaner is 100% guaranteed to either
a) crash computer by pulling plug to power industrial vacuum machine
or (slightly smarter facility hygene operative)
b) plug industrial vacuum machine* into empty socket next to computer, thus tripping circuit
*floor polishers are also good for this, as we discovered by correlating our regular teaching PC lab failures with the caretakers weekly rounds...
"The fan blowing air in should have a filter in front of it. I got mine on eBuyer I think for a couple of quid"
Hmm, that'll teach me to be such a cheapskate. I bought my fan for a dollar on eBay.
I cried, bitterly when my one packed up in less than two years. The motor still worked, but the lube didn't.
"sounds like my ex-wifes reason for giving up on sex"
You should have tried what I did:
In the five weeks or so it took for the replacement fan to arrive from China I found that if I drizzled a little canola oil into the old fan, as a kind of lube, it would work fine for a couple of days before gradually becoming more noisy then seizing up again.
Pro tip: canola oil doth not a good lube make (for fans). Other oils may perform differently; YMMV.
"I think you'd need to have a fan that pulled air into the box through an easily-changed filter, to have much hope of success."
That's how I "bodged" of a fix for a customer who was on the verge of having his maintenance contract tripled in price or being told to bog off. The problem was that the office was in a workshop unit making garden statues/models/frogs/gnomes etc. Very, very dusty and the office PC (yes, just the one, we're talking MS-DOS days here!) had a tape drive in it that used an optical sensor and hole in the tape to mark the end. Cue dust on the sensor and tape ripped of the end of the spool pretty much every month, which was how long it survived after cleaning.
The "bodge" was to open up the PSU, reverse the polarity of the electron flow and now the fan sucks instead of blows! I suggested that they now try to source a filter for the air "inlet", meantime, stick a sheet of toilet tissue over it and the suction will hold it in place, not forgetting to replace it every morning. The contract ran out about 7 months later and I only ever went back once in that time for an unrelated fault. They were still placing a sheet of bog roll over the fan inlet every day.
On the subject of filters, I recently stumbled across this company, which apparently does only dust filters for computers:
I've ordered 2 for my gaming machine, and they're absolutely top-notch ! Only problem is they ship from South-Africa which cost arms and legs.
"not curious enough to type 'dust proof pc' into the Googles?"
You got a plus vote from me for that.
However, I fully understand the negs (3 for you currently) because of your ill chosen use of the word 'Googles'
Unfortunately it's probably too late for you to replace 'Googles' with 'Ducks' to appease all of the privacy invasion hating commentards that inhabit this offbeat corner of teh interwebs.
@Mycho, but not curious enough to type 'dust proof pc' into the Googles?
Nope, not that curious.
Though I did take the advantage of a dull Friday to eyeball a few work PC innards just to be sure. Couldn't believe how shiny they were, must be doing something better than at home.
> the normal trick for dustproofing
Keeping it in a dustproofed area is the only guarantee.
Failing that, a room or section of room with something simple like net curtains at the doorway is enough to stop plaster (top quality fine dust) floating through and coating everything - though don't use too small a space for your dust-free zone (e.g. the space under a desk) as the this is enough to restrict the external airflow and put the temperature up by 10-20 degrees and in an already-warm environment that might be all it needs.
Assuming you can't add an intake fan with a replaceable filter.
What's the normal trick for dustproofing a computer?
Well taking my cue from the article (ie. cheap and using components that are readily obtainable in most high streets) and assuming the computer is more of a i7/Xeon workstation than a fanless all-in-one...
The first thing is to get rid of the external fans and filters! as these will get clogged unless regularly maintained. So what you need is to install the computer inside a sealed box with a refrigeration system and a container of silica gel - a bit like an old water cooled mainframe...
So the DIY approach is potentially an old freezer with some modifications to facilitate cooling... Obviously, even here the cooling panels will attract dust and hence require periodic cleaning - which can be done with a broom....
More seriously (ie. you have micro/SMB clients who actually want to use computers in 'challenging' environments where the air contains dust, solvents, grease and other grime but aren't prepared to pay the full costs of a proper solution), there is a market in secondhand rack cabinets which, if you have a van and so are able to collect, you can pick up the "professional" version of the above for a small fraction of the price of buying new.
Back in the day of newsgroups there was a rather noisy one I lurked on once in a while. It was very east coast US oriented which made it rather boring for someone in Blighty.
Still there was one thread where someone suggested that they could weatherproof their PC by filling it with closed cell foam. There were some jokes about how it could double up as a lifejacket but I never heard how quickly it cooked itself.
But, he knew about computers ! He had one !
And that is why that line never works. The moral of the story is more like : only people recognized for knowing about computers by people who know about computers should be allowed to order computers.
And the second moral is : only suppliers who already have dust-proof computers that actually work should be allowed to sell dust-proof computers.
But the line about the lowest bidder is totally true in PC equipment. When I buy a component to upgrade my PC, I buy the best I can afford, I don't skimp on the price. If I can't afford it, I won't buy it. Of course, that does mean I might have to wait a bit.
I was once in a taxi in Madras which broke down because the owner had cleverly wrapped the dynamo (yes, dynamo) in a plastic bag to keep the water out in the monsoon period, and the bag had melted onto the dynamo.
With me in the taxi was a director of Ashok Leyland. He was highly amused. The driver was not.
In a previous job I was called to the steel warehouse in a factory as the screen of the terminal there was apparently unreadable and dark.
I went down to the floor past all the welders, presses and grinders making vehicle component and arrived at the stores. The poor guy could not allocate stock or order jobs from his screen.
Diagnosis: Step 1 Adjust brightness to little effect which is unusual. Step 2 A quick (and subsequently regretted) wipe with a forefinger revealed the hellish glare of the full amber screen brightness languishing under a very thick layer of steel dust/rust. The screen, the terminal box, and basically everything in the area was covered in a thick layer. If this had been a PC with a fan it would have been nicely shorting itself out long ago...
We thoroughly cleaned the right hand half of the screen and suggested that the team there provided themselves a (relatively) clean cloth to wipe the screen with on occasion.
There was also a very nice, burn-in of the login screen on the display where full brightness of a static image had been for uncounted hours of service.
Reminds me of the time I offered to fix the CCTV system of the small shop across the road. Can't remember the fault, but I do remember that I fired up the monitor on my workbench and was surprised to see a pretty good image of the off-licence. It was so clear that it had me looking for unseen inputs for about 10 seconds until I realised it was screen burn.
@Niall Mac Caughey; The CRT monitor connected to my boss's old CCTV system had screen burn that was identifiably the shop interior the camera had been pointed at even when turned off- but yours sounds like a pretty extreme case.
Around 10 or more years ago I bought a budget compilation of classic Atari arcade games for the PC. One of them was an authentic-as-possible rendition of the classic wireframe Asteroids, and it included the option to set it as a screensaver. (Remember when people used to get excited about novelty screensavers?)
When you remember what screen savers were actually meant to do originally- i.e. protect the screen from burn-in- this struck me as hugely ironic; the design of Asteroids (bright, sharp-edged text appearing located at fixed positions) meant that at least one machine I saw in the late 80s had really obvious screen burn.
Granted, the PC was running a raster scan CRT that was only emulating the appearance of the original machine's vector scan and probably wouldn't have been as bright. Plus, by that point, screensavers seemed to be more prized for their novelty/fad value than their original use. Monitors were much cheaper by that point (early-2000s) anyway, so I guess it wasn't that big a deal.
I guess the passing of the fad and the fact that everyone uses LCD monitors nowadays (which don't really suffer from screen burn in the same way) explains why I can't remember the last time anyone really gave a damn about screensavers.
Nowadays your PC or laptop does "screen saving" by turning off, more or less. Or by turning everything off. It's a standard feature and it saves electricity.
You can however set the display to stay on, for applications where the device needs to keep running while not being touched.
The screen saver or lock screen mainly reminds you that you haven't actually turned the PC off.
Had to clean a computer used at for site-work at Sellafield. When the case was opened there was a thick layer of grime on the motherboard, deep enough to grow vegetables, if it didn't contain so much metal.
The only reason the motherboard hadn't shorted was that the Sellafield dirt was sitting on the dried mud from a previous site. As it was, the 386 happily chugged along regardless.
"As it was, the 386 happily chugged along regardless."
The 386 was a very good little processor. So was the PowerPC, which went on to power a lot of printers. We had one Lexmark which failed due to a borked cpu fan; instead I glued a small heatsink on the processor with a little silver loaded epoxy and it worked just fine.
from the early days of a computer in every business of how a small, traditional, pizza company / Italian diner had 'modernised' with a ZX Spectrum that ran the accounts, stock control and provided recipes. It sat on a shelf at the back of the kitchen. But spinning dough in the air inevitably led to the odd pizza base flying off and ending up flung into some corner or other until the kitchen was cleaned down at the end of the day. Yep. Cooked pizza, but the computer survived to print another invoice.
I don't know. I assume it was home written, probably some kind of computer studies O-level or A-level project. Load once from a micro drive, leave it running, enter the bills at the end of the day to see what menu items are most popular etc. The Spectrum was king of the home brew.
i installed pcs pentiums ii and iii's into pizza shops. the flour covered the motherboards and smelled like bread. as long as they were left on the fans kept spinning. the shops were warm and dry so it never congealed onto fans and jammed them.
also had a 386 in a machine shop office above work floor in early 90s. they kept blowing due to fine metal dust from work shop that found it's way up to high office and into power supply. we eventually put the base unit in a pair of tights with a hole cut into leg which hung over the floppy drive. never gave trouble after that. wouldn't work with an air cooled pc though... looked silly but it worked.
I worked for a train maintenance firm for a while, some of their on-site support calls were interesting to say the least.
Wanging a 90m cat5 cable over the roof struts of Ramsgate repair shed to connect two pcs together was a particualr highlight. Nerf guns have never been the same since
I should take a picture of the system I built like that. I took about 30 1U server boards (Old Dell PE-1850 boards), used a bunch of 2 inch motherboard standoffs to link them together and dunked them into a 50 gallon fish tank full of mineral oil. The tank was originally designed for cold-water fish so had a big cooling rod built into it (got it surplus from the local NOAA / Oceanic Research lab).
The monstrosity was used to house a compute cluster for research lab. They didn't have space for a dedicated server closet and everything in lab had to be explosion-resistant, so the servers were dunked into the tank along with a pair of 48-port switches with fiber GBICs to communicate with the outside world
Moral of the story: Cheap is always expensive.
It's funny though I remember my Dad saying the once that the guys who would work in the office on the building site knew feck all and plenty of it. Suppose 50/60 years of working on building sites dealing with the agents and other "clowns" (as he'd put it) would make you think like that.
And this article proves it.
> Moral of the story: Cheap is always expensive
Like when (in the mid-90's) we bought a bunch of PCs from a 'new' supplier in Korea/Taiwan (I forget which) called Trigem.
First batch arrived with 120v PSUs (with no warning - we had ordered 240v PSUs). Cue lots of sparks and the smell of frying electronics.
Trigem replaced them with 120/240v switchable PSUs. First batch, not a problem. Second batch, all the PSUs were set to 120v. Again, cue the smell of frying electronics.
We bought from UK suppliers after that.
Once replacing computers at Novartis, we pulled a production computer that was internally caked in 2" worth of various drugs in dust format. Machine worked fine though to its credit considering how good a insulator all that powder must of been.
Safe to say that went outside very quickly and was pushed off a cart with a long broom handle, whilst we stood round nervously chortling at the clouds of dust billowing away.
Really should of recorded it :/
There are industrial PCs made expressly for this type of situation. They are typically rack mount, but I've seen desktops before. The cases have filters at all air entry/exit points. Where I work, some of the machine controllers are vendor-supplied, and have cases like this even though they're not really needed in our environment.
Over a decade ago I worked a job where I did Point of Sale systems support. The PCs were mostly made by NCR, ran Red Hat or SCO UNIX, and ran a slew of dumb terminals and printers through a serial terminal server box. These PCs had an enormous heat sink on the processor, which was fanless. A lot of them had been running 24/7/365 for 10+ years. They were nearly all located in the restaurant kitchen where the temp could get up to over 100F in the summer. (restaurants are not known for great climate control in their kitchens)
Usually I would find that the power supply fan and case fan had long since stopped turning, and the fans and some internals were coated with a think layer of sticky brown goo, from ingesting the greasy vapors in the kitchen air. (Imagine what it must have been doing to the lungs of workers over time) To their credit, NCR built a heck of a reliable box. Even with all this, I only ever saw 2 motherboard failures. One from natural causes, and one from a mouse living in the case and defecating/urinating on the system board until its urine eventually corroded through one of the traces that ran the PCI bus, stopping communication with the rest of the terminals. (the machine was still running) That one was such a biohazard I pulled the drives and the rest went in the dumpster.
I was once asked by an insurance company to inspect and provide a repair report for a PC that had been struck by lightening. The PC was housed abroad in a remote location onsite, and the telegraph pole outside the building had been struck by lightning, travelled down the cable, through the modem and into the PC.
A few days later the PC arrived packaged up, From the outside it just looked like your average dirty beige box PC from the late 90's, nothing untoward. Then I opened it up. The interior was charred black. In the bottom of the case was what looked like a big pile of solidified pink porridge, as though everything inside the case had simply melted and fused together. I could never figure out the pink tho.
The follow up phonecall with the insurance company was amusing tho. I was asked if the damage was consistant with that caused by lightning strike. I was then asked to provide a quotation for repair. she was adamant repair would be cheaper than replacement. In the end I simply provided an itemised bill that listed every part within the PC, and labour. I then shipped out a new PC.
Insurance adjusters never take warranty into account because they think they're not obliged to do provide one on the repairs.
I'm reminded of an incident with my motorcyle where a damaged plastic panel needed replacement. The adjuster insisted on repainting the entire thing. After 5 trips back to the paintshop because none of the panels had matching colours, it finally came back acceptable - and the repairers snapped one reinstalling it, so replaced with a factory item.
4 months later none of the panels were the same colour - nor did they match the factory one, so the lot went into a skip and were replaced with factory originals. Apparently the final cost was 8 times that of just replacing the damaged panels and last I heard the assessor was working in McDonalds.
On one occasion I had to drive all the way up to somewhere near Leeds after a lightning strike took out some kit attached to a weigh bridge at a quarry.
220 miles each way to spend 15 minutes replacing a single board just because the area service engineer was on holiday...
I had a lightning strike experience when I was working a point-of-sale support job. The strip mall where one of the restaurant units I supported was struck by lightning in the wee hours of the morning. I arrived to find a long line of contractor and repair vans all down the row of shops, as no one had been spared. After I finished replacing the phone system, server, one of the dumb terminals, and the power supply for the credit card terminal, everything was working acceptably again. (the electronic safe was still fried, but I couldn't do anything about that)
I remember a guy who used to work for me - back in the days when I ran a team of telephone engineers - who brought in a charred and generally crispy Line Card ftom a business telephone system. Attached to it was the usual red tag with a fault description of "F*c*ed by Lightning".
I explained that his fault description really wasn't appropriate and that it should say "destroyed by lightning - beyond economical repair". He duly changed the label.
Two days later, he was called back to the same customer's office, for the same kind of fault. This time the strike had been rather more powerful and had actually ripped the line card in half! This time, the red label tying the two pieces together read "Totally phuqued by lightning"!!
"This time the strike had been rather more powerful and had actually ripped the line card in half! "
In a former telco existance I've walked into a comms hut to find blackened ends of wires where the line cards (40-50 of them) and their edge connectors used to be.
One hilltop site which took a direct hit had the mains board blown off the wall - and embedded in the one opposite. This was the old ceramic rewireable fuseholder technology. The amount of energy in a lightning strike makes most checmical explosives seem minor.
In the late 90's, company I worked for put up Tsunami 2.4Ghz transmitters in towers around Tucson, Arizona that could push a wireless signal about 5km line of sight, creating one of the first point-to-point consumer wireless connections in the country. It was done on the cheap (ok gear wasn't cheap, but the owner of said company should have bought spectrum since he was throwing money around), but we used Cisco 48 port switches with T1/T3 connections to each tower for packet traffic.
There was one important tower close to downtown that got hit with lightning literally every storm and would take it down. Credit goes to Cisco with their robust switches, we would have to go to the tower, simply move the ethernet cable over to another port, and connectivity was restored. That tower's switch would get replaced roughly every two years after it ran out of ports - owner of that tower never did figure out why it was such a lightning magnet or ever get t grounded properly. Mysteries of the Unknown shit.
"owner of that tower never did figure out why it was such a lightning magnet or ever get t grounded properly."
Getting it grounded would have made it even more of a magnet and grounding a tower in a desert environment (T00son is one of the driest environments I've been in) is a lot more easily said than done unless you have the gubbins to bury a metal mesh 2-3 feet down across a couple of acres.
One method to cool industrial computers is to have filters on the intakes to the cabinet housing the electronics for the machine and plenty of room in the cabinets to deal with reduced airflow when they are reaching the end of the filter exchange period. These are changed out to a maintenance schedule along with other service items and everything is happy.
Another method is to totally seal the case, but use the case itself as the heatsink to disperse internal heat, this way there is no filters to clog but it requires the machine to be designed that way from the start.
Using the case as a heatsink is the best method, and some computers like the Newton V are doing that for the home/office/education, not only industrial ones.
It is the more expensive way of doing things, but also the best, unless you need serious power, then you really can't use this approach.
Gulf War 2, lets deploy JOCS to somewhere hot and sandy. The quote for dust proofing the server containers was rejected due to cost. When all the kit came back it then had to be sent for specialist cleaning at a far greater cost.
I don't know if any of it failed out in theatre, location I was at had a vacuum cleaner which we went over the IT kit daily with. Servers were in a positively pressured container to reduce the ingest of dusty stuff.
I worked on a project a while back which had many remote sites, each with its own server cluster and a shared SCSI JBOD (OK, a long while back!). The design was all IBM and worked fine through testing. Come to ordering and the purchasing manager decided to save a few quid by replacing the IBM HBAs with some cheaper cards from Taiwan. Not surprisingly, despite the Taiwanese manufacturer's claims, they did not prove to be as reliable as the IBM hardware, and the project lost time and money as we had to keep sending engineers out to the remote sites on a regular basis to replace the cheap HBAs. Not surprisingly, the purchasing manager was let go soon after.
I worked in one of those road construction Portacabins back in the early 1990s. Looking after three 386s used by the Consulting Engineers. It was when I witnessed my first hard disk failure. The disk had literally frozen. I don't mean frozen not moving... I meant it was a block of ice after the Portacabins had dropped to minus somehing silly overnight....
Or a few years back when I looked at the CCTV system of a Chinese Restaurant. That was an "interesting" gunky mess on everything inside!! Not much you can clean when it is that bad, so had to make do with replacing fans.
Or the farm building where a company made concrete kerbs \ slabs \ etc. Concrete dust into moulds. Wow!! That PC was at the far end of the building away from the workers, but EVERY service inside was covered with an INCH DEEP of fine concrete dust. Gawd only knows what was happening to the hard disk as it would surely get through the breath hole.
As is always the way, the concrete guy didn't want to pay out for expensive dust proofing. So my ideas came up with ways of reducing the dust into the room. They didn't like anything so fancy as a *door* - but I managed to at least get them to put a curtain up. That PC also got a new external box built for it. So the PC Tower case then sat inside a separate filtered cage made from wood and material. Did the job...
worst ones I've seen like that were in a light engineering company that built lifting gear -cranes / pulleys etc.
everything in the office was coated in a thick layer of fine red dust: rust, and so were the insides of the PCs. I found it remarkable that the PCs didn't fail more often, but I only had to replace two PSUs over three years (they had five machines in total). Never had a motherboard fault.
remarkable really -just proves how much crap some machines can take
I almost strangled the construction workers after arriving at the office and seeing a sheet of plastic over my workstation - luckily, both for my workstation and liberty, picl reported temperatures just a tad above normal. It wasn't anywhere near a complete wrap like this, rather formed a tent with openings at the bottom.
Back in the late 80s we had a 286 in one of those big XT/AT cases in our assay lab. It never seemed to have any issues despite all the rock and lead dust (lead ii yellow being the main reagent used). We eventually opened it up one night to find everything inside coated with an inch of lead/rock dust but the machine didn't seem to mind, so we left it alone rather than disturb it all by attempting to clean it.
Lead II Oxide (PbO)
Hence all the safety equipment (HEPA etc.) and the frequent blood tests, though most of us who grew up when leaded fuels were used were exposed to far more lead from car exhausts.
The more immediate health issues were from dealing with the heat involved with blast furnaces, the molten rock they produce and other elements that were in the rock and might be cooking off like nickel and chromium and stuff.
That poor 286 was built like a tank, though I can't remember if it was a Compaq or something crazy like a Packard Bell...
Working in a print shop as a millwright, we had an IBM Series 360 data entry system that would output print data in the form of 7bit punch tape. The correction terminal was located in the pre-press LinoType area where the lead mats for printing were made.
See the above link to find out what a LinoType is.
The terminal was located between two of four Linos that all faced each other in a circle so that one operator could run all four of them with the terminal shoved in between somewhere. The problem was that the Linos used liquid lead to make the mats for printing and would sling shards of lead all over the place, including the keyboard for the terminal. When the keyboard got full of lead,shorting out the open switches for each character, the operator would run up to the front office data entry cubes and swap out the keyboard with the failed one from in back.
Not telling anyone what he had done, when a new data entry clerk came in and was assigned a front end terminal, of course the terminal failed because of a bad keyboard. I would get a call for the terminal failure and would determine that the keyboard was the problem. I would replace it with my only spare and fire it up and go. After 10's of time of cleaning lead out of keyboards (I couldn't figure how lead got up front) the print shop supervisor found out what was happening with the Lino operator just doing this on his own prerogative.
Soon afterwards, I had six spare keyboards and all the spare parts/boards to repair them. I placed the correction terminal on a weekly schedule to swap the keyboard out for service/cleaning, and corporate was soon shipping me every bad keyboard from over 20 different plants. So was my entry into the computer service/repair industry.
But, my real love was for the Lino's, and so much for the operators!
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