todd@ivucsb.sba.ca.us (Todd Day) (06/14/89)
I was putting in some more memory into my UNIXPC, when all of a sudden, it refused to boot. Thinking I may have bent one of the Eurocard connector pins, I opened it up. What I found was a few gnarly dust bunnies smashed inside the connector. There was no metal in the area that I could see. After doing a thorough vacuuming job, I got the machine to boot. Are dust bunnies electrically conductive in ANY way? -- Todd Day | todd@ivucsb.sba.ca.us | ivucsb!todd@anise.acc.com "All theory, no practice. That's the story of my life."
nigel@censor.UUCP (Nigel Burnett) (06/15/89)
To: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!anise!ivucsb!todd Subject: Re: Conductive Dust Bunnies In-reply-to: your article <1989Jun14.042949.597@ivucsb.sba.ca.us> yes - dust bunnies are conductive - Bell Canada has just mounted a big 'education' programme' with a video featuring long haired rabbits and inserts in the monthly bill admonishing people to vacuum out their modular jacks in their weekly (!?!?!!) cleaning (monthly at best - maybe once/year?) Anyway - yes - the dust will do it. Nigel Burnett
jep@oink.UUCP (James E. Prior) (06/15/89)
In article <1989Jun14.042949.597@ivucsb.sba.ca.us> todd@ivucsb.UUCP (Todd Day) writes: ... >Are dust bunnies electrically conductive in ANY way? Most aren't. Unless you're in a machine shop with steel wool dust bunnies. Ordinary dust can be slightly conductive when soggy from humidity. The biggest problem that dust bunnies cause is merely mechanical blockage of airflow, which causes circuits to overheat. -- Jim Prior jep@oink osu-cis!n8emr!oink!jep N8KSM
thad@cup.portal.com (Thad P Floryan) (06/16/89)
Re: Todd Day's "gnarly dust bunnies" ... Nope, they're not conductors but, instead, insulators! Meaning that when you mashed several dust bunnies between the card edge and the Eurocard connector you isolated the card ... not a SHORT but an OPEN ... no signal(s) can breach the Bunny Barrier. :-) Thad Floryan [ thad@cup.portal.com (OR) ..!sun!portal!cup.portal.com!thad ]
levy@cbnewsc.ATT.COM (Daniel R. Levy) (06/16/89)
In article <1989Jun14.042949.597@ivucsb.sba.ca.us>, todd@ivucsb.sba.ca.us (Todd Day) writes:
< I was putting in some more memory into my UNIXPC, when all of a
< sudden, it refused to boot. Thinking I may have bent one of the
< Eurocard connector pins, I opened it up. What I found was a few
< gnarly dust bunnies smashed inside the connector. There was no
< metal in the area that I could see. After doing a thorough vacuuming
< job, I got the machine to boot.
<
< Are dust bunnies electrically conductive in ANY way?
I'd have bet on them being insulating: the dust got between a pin and a
contact finger, holding them apart.
--
Daniel R. Levy UNIX(R) mail: att!ttbcad!levy, att!cbnewsc!levy
AT&T Bell Laboratories
5555 West Touhy Avenue Any opinions expressed in the message above are
Skokie, Illinois 60077 mine, and not necessarily AT&T's.fiesta@cbnewsi.ATT.COM (eric.c.beck) (06/23/89)
> The average office environment is filled with conductive dust. This dust > can be purchased at many stationary stores, to buy it just ask for > photocopier toner (laser printer toner works too). This dust is mostly > carbon, often with some paraffin wax. I thought the toner consisted of extremely fine plastic particles which, after being attracted to the paper by a static charge, are melted into the paper by the "hot plate" inside the copier. > photocopier. If you want to know how much toner they throw into the > atmosphere, look at the walls and carpet or your photocopier room. Black > lung disease an occupational health problem in the reprographics dept? A copier tech once told me that the toner could be absorbed into the body through the skin (!?) afterwhich it would collect in the kidneys and cause "permanent" damage (e.g. clog them up). Anybody else ever here of this?? Eric Beck fiesta@homxb.att.com
brian@ucsd.EDU (Brian Kantor) (06/23/89)
And putting the pencil sharpener on top of your PC is a mistake. - Brian
henry@utzoo.uucp (Henry Spencer) (06/25/89)
In article <321@cbnewsi.ATT.COM> fiesta@cbnewsi.ATT.COM (eric.c.beck) writes: >> photocopier toner (laser printer toner works too). This dust is mostly >> carbon, often with some paraffin wax. > > I thought the toner consisted of extremely fine plastic particles >which, after being attracted to the paper by a static charge, are melted >into the paper by the "hot plate" inside the copier. Pretty much so. However, there has to be a pigment to make them black, and carbon is the usual choice -- it's cheap, very black, and chemically benign. Most black inks are likewise carbon-based. -- NASA is to spaceflight as the | Henry Spencer at U of Toronto Zoology US government is to freedom. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
friedl@vsi.COM (Stephen J. Friedl) (06/26/89)
In article <321@cbnewsi.ATT.COM>, fiesta@cbnewsi.ATT.COM (eric.c.beck) writes: > > I thought the toner consisted of extremely fine plastic particles > which, after being attracted to the paper by a static charge, are melted > into the paper by the "hot plate" inside the copier. There are also toners that apparently have metal particles in them, because it is attracted to a magnet. The Ricoh laser engine (used in AST TurboLaser, at least) has this kind of toner. Does anybody know this is different from the non-ferrous kinds? BTW, the "hot plate" is called the fuser. Steve -- Stephen J. Friedl / V-Systems, Inc. / Santa Ana, CA / +1 714 545 6442 3B2-kind-of-guy / friedl@vsi.com / {attmail, uunet, etc}!vsi!friedl ---> vsi!bang!friedl <-- NEW "Friends don't let friends run Xenix" - me
jb@aablue.UUCP (John B Scalia) (06/30/89)
In article <1137@vsi.COM> friedl@vsi.COM (Stephen J. Friedl) writes: >In article <321@cbnewsi.ATT.COM>, fiesta@cbnewsi.ATT.COM (eric.c.beck) writes: >> >> I thought the toner consisted of extremely fine plastic particles >> which, after being attracted to the paper by a static charge, are melted >> into the paper by the "hot plate" inside the copier. > >There are also toners that apparently have metal particles in them, >because it is attracted to a magnet. The Ricoh laser engine (used >in AST TurboLaser, at least) has this kind of toner. Does anybody >know this is different from the non-ferrous kinds? > Steve, that's not really the same stuff. Toners are basically variations of compounds made of carbon black with some carrier, usually a plastic. (Xerox typically uses Styrene, Acrylate Copolymer, although some of the older ones used exotic stuff like Bisphenol A Propylene Oxide Fumarate.) Other brands will also have a mouthful for the carrier. The stuff with the steel in it is the developer, something totally different yet required for operation. Developer is often simply 95% steel shot or iron powder and some lubricator. Again, Xerox uses Polymethylmethacrylate. Yes, in some smaller machines, the mfgr may package both in the same container, but it's unlikely. Your copier will, however, mix the 2 when it runs. Typically, as well, you'll never come in contact with the developer. Changing developer is for what you pay a service contract. You may come in contact with the toner, as the end user is often expected to add it as needed and neophytes often don't know how to be gentle with the bottle and get it all over them, the room, etc. None of this stuff is really toxic or dangerous. All of it is rather stable. If you're really concerned about how healthy it is to be around it, ask about getting a copy of any relevant Material Safety Data Sheets, MSDS for short, on every applicable component in your copier. The manufacturer/distributor is required by law to make these available to you, and your employer must allow you access to these forms, again by law. Conventional copiers will have 3 chemicals(?) that should be covered by the MSDS's: Toner, Developer, and the photoreceptor itself. You may also have copies of the MSDS forms for any cleaners, etc. it may use. Of course, reading these things and making some sense out of them is another matter. Of course, if you need Xerox information, call 1-800-828-6571. John B. Scalia Just a guy at a firm that happens to sell copiers and is in charge of the MSDS information. -- A A Blueprint Co., Inc. - Akron, Ohio +1 216 794-8803 voice UUCP: {uunet!}aablue!jb Sometimes they do let me speak for the company, not today though.
ralph@rtech.rtech.com (Ralph Harnden: I don't wanna badger you (ext3430)) (07/22/89)
In article <19559@cup.portal.com> mmm@cup.portal.com (Mark Robert Thorson) writes: ... >When I first heard this, it gave me a great idea for "nuking" a computer >center. Get a bunch of graphite fiber, chop it up, and dump it into the >air conditioner intake for the building housing the computer center. > >Of course, I never did it. And you shouldn't either. ;-) In a past life, I worked for a large mainframe vendor. One of their customers destroyed a multimilliondollar machine by drilling holes in a metal door frame close to the power distribution unit for the dinosaur. The power supply fans sucked the metal filings (dust...) up into the unit; the result was a virtual meltdown. The vendor had to mechanically replace the entire machine. The moral of this fable is: dust is not dust is not dust! I'm not suggesting that the original poster send his dust bunnies to the lab for testing before he removes them. I would caution, however, that unless you suspect there is conductive material in the dust, or unless you observe the dust blocking the vents, removing it can cause more damage than just leaving it alone. Especially if you are not aware of static dischange, or the magnetic fields generated by vacuum cleaner motors. -- "People will do anything for a potato" {amdahl, mtxinu, pacbell, sun}!rtech!gusano!ralph ralph%gusano@rtech.com
mmm@cup.portal.com (Mark Robert Thorson) (07/22/89)
I had a pdp-11/15 (still have it, wanna buy it?) in which about half the instruction set was intermittent. I noticed that years of use had left some of the chips near the fan caked with dust. I pulled out all the boards and washed them with detergent, and that fixed everything up, no more problems. BTW, conductive dust was an early objection to the introduction of widespread use of graphite-reinforced plastics. When I first heard this, it gave me a great idea for "nuking" a computer center. Get a bunch of graphite fiber, chop it up, and dump it into the air conditioner intake for the building housing the computer center. Of course, I never did it. And you shouldn't either. ;-)
julian@bongo.UUCP (julian macassey) (07/23/89)
In article <19559@cup.portal.com>, mmm@cup.portal.com (Mark Robert Thorson) writes: > > BTW, conductive dust was an early objection to the introduction of widespread > use of graphite-reinforced plastics. > > When I first heard this, it gave me a great idea for "nuking" a computer > center. Get a bunch of graphite fiber, chop it up, and dump it into the > air conditioner intake for the building housing the computer center. > > Of course, I never did it. And you shouldn't either. ;-) The average office environment is filled with conductive dust. This dust can be purchased at many stationary stores, to buy it just ask for photocopier toner (laser printer toner works too). This dust is mostly carbon, often with some paraffin wax. Many office PBX's and computers have had "weird" problems when in the same room with "The other machines", this usually means a monster photocopier. If you want to know how much toner they throw into the atmosphere, look at the walls and carpet or your photocopier room. Black lung disease an occupational health problem in the reprographics dept? Yours. -- Julian Macassey, n6are julian@bongo ucla-an!denwa!bongo!julian n6are@wb6ymh (Packet Radio) n6are.ampr.org [44.16.0.81] voice (213) 653-4495
bph@buengc.BU.EDU (Blair P. Houghton) (08/13/89)
In article <224@bongo.UUCP> julian@bongo.UUCP (julian macassey) writes: > > The average office environment is filled with conductive dust. This dust >can be purchased at many stationary stores, to buy it just ask for >photocopier toner (laser printer toner works too). This dust is mostly >carbon, often with some paraffin wax. > > Many office PBX's and computers have had "weird" problems when in the >same room with "The other machines", this usually means a monster >photocopier. You just described a local copy center, which also contains the building's central security computer, diskdrives and all... I'm just waiting for the door alarms to start playing "How Dry I Am." --Blair "No, I'm not going to tell you which one."