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**Slider2732** · 07-05-2012, 06:49 AM

OK, here comes a rambling post

From the top, here's what I would put in nicely labeled boxes and draws *cough* more like a pile, that sort of stays in one area, but invariably things end up all over the place.

Running computers - The PII's will run freebie oscilloscope programs found online and you can set one up to just run such software. Alternatively, there are Linux distro's that will boot from a CD, need no harddrive, like Puppy Linux. You could use those old PC's for Parallel port experiments...running motors from the PC and the like and if you break something it doesn't matter as much as busting a 1 year old PC.

Power supplies - If any power supplies are working, a good mod is to convert one to a bench power supply. There are many op-amp circuits that require a -12V supply and PC power supplies have them. For ATX types, simply cut a black ground and the green wire and connect them together. Put an old PC fan on any 12V and ground connection, so that the power supply has something to do. The supply will now start up and you have 3.3V, 5V, 12V and -12V available with heavy use amperage if required (just read the label for what's available).
For broken supplies there are often TL494 chips on them, handy for magnetic levitators, for one thing. Good sized toroids will be inside, a couple of decent MOSFET's, mains capacitors, large wattage resistors. Plus, it's always good to reuse that thick load of wiring for battery connections.
A tip - some supplies have male and female 4 pin connectors. You can use those as quick connects/disconnects in heavy amp circuits.

Broken PC keyboards - There are at least the 3 LED's on the top right you can salvage

Use the cords for the thin wiring inside, as general purpose wiring.
I used to trace the wiring of keys back to the controller chip and then reconnect those connections to joysticks/buttons on PC based arcade machines (dual booting with original circuit board if it was a good cabinet and game). Such that, the keyboard plastics are junked, but the circuit and connections lived on. You might find other input uses with a keyboard circuit board...it will still just plug in to the keyboard connector of the PC of course. Some projects can have a neat and tidy mounting by reusing the flat rear plastic piece of a keyboard.

Analogue CRT monitors - One of my favourites for salvage !
The degauss coil is usually of approx 24 gauge copper and the black taping on them can usually be readily removed on older monitors. 100's of feet on those. Removing the screw clamps will allow removal of the neck gubbins. On that gubbins are actually 2 good multi-strand coils, with adjustable ferrite pieces inside. Under the gubbins you can salvage the 2 piece ferrite collar, making sure to not lose the little clips that keep them together. Also, outside and inside the ferrite collar is a huge amount of usually multi-stranded wire of around 30 gauge per strand. It normally has what seems to be tough glue securing the strandings, but in fact doesn't bust the enamel coating when pulling the wiring apart.
The circuit boards are full of 555 timers, MOSFET's (usually IRF630's) 1500V flyback transistors (for Bedini wheels etc), bunches of coils, resistors, caps, a relay, LED's, variable pots, connectors and more. Don't forget the flyback itself...if the monitor switches on and doesn't make crackling noises after a few minutes, then the flyback should be fine. You will also know everything else will be fine for salvage too.

CD drives - inside every laser assembly are 2 small neodymium magnets. Collect 2 sets from 2 drives and you have magnets for a 4 magnet Adam's motor or similar projects.
The motor in most drives can be rewired to make a strong RC brushless motor. I fly quite a few planes with my own converted motors, on planes up to 7oz weight. If the magnet ring is silver in colour then it will work for that use (stronger than the blacker or very dull grey versions).
There are a couple of Mabuchi motors inside drives too, useful as they are, or you can take them apart for the 30's gauge wiring. Finally, a green or orange LED on the front to be salvaged and perhaps the audio plug and volume wheel/pot.

Hard drives - always salvage the neodymiums. They are huge and well worth the effort of dissecting screw assemblies. A tip for awkward star type screws that are often used on drives....a Dremmel. Cut a flat line with a round sanding disk fitted, Now, a regular flatblade screwdriver will work to remove them

If you find thin but large neo's, you can make them any size you want, with the careful use of pliers. Pliers with a sharp edge toward the handle work great. Place the neo in the jaws to the placement required and gently increase pressure. The neo will snap but lose zero power and be the size you want.

Modems - Ferrite chokes, caps, resistors, 1:1 transformers (see the Don Smith thread for recent developments by Jack Noskills regarding 1:1 trafo's).
The edges are often gold plated too on an ISA card, not that you'd be a millionaire with even 16 of them.

TV's - Yeah similar to CRT monitors. Though, you might well find a lot more hard to find small signal transistors on the TV's, depending on the age.

Microwave - Approx 1uF 2300V cap. 2x huge disc magnets. 120V bulb and holder, 120V motor and fan, turntable 4Hz or so motor. Circuit board parts, couple of microswitches in the door area. And the main thing, the 2KV transformer, as seen in many Jacob's Ladder experiments on YouTube.
Perhaps the use of the casing for a Faraday Cage, if it seals well and you plug the turntable area if the motor is removed. Same applies for any holes within the main cooking area sides.

Hope that helps

**boguslaw** · 07-05-2012, 07:58 AM

Also, outside and inside the ferrite collar is a huge amount of usually multi-stranded wire of around 30 gauge per strand. It normally has what seems to be tough glue securing the strandings, but in fact doesn't bust the enamel coating when pulling the wiring apart.

Yes,I found in one or two this multi-stranded enamelled wire but most of other have just a coil of single wire heavy glued. I found it impossible to dismantle this wire after a lot of tries with various solvents and heating with air and water :-( Any ideas ? At the end I took it all to the scrap yard. Probably it's not worth to try to salvage wire from such coils.

**wrtner** · 07-05-2012, 08:32 AM

Originally posted by Slider2732 View Post

Perhaps the use of the casing for a Faraday Cage

Don't forget that the door is a form of glass with a crude metal
gauze arrangement. Is that good enough for a faraday cage?

I would have thought that the PC bodies would be better if the
front panel is steel and the various drillings and holes are made good.

A couple of thoughts:

1. The caps will probably have a 1megohm resistor inside the casing across
the terminals.

2. There will be some useful high voltage diodes to be recovered.

3. The recent (less heavy) ovens do not have a transformer but an
exotic high voltage psu which should be looked into.

4. I have got the coils out of the transformer by cutting through the
steel with an angle grinder and soaking the whole business in water
for two days to make the cardboard packing around the coils soft.
Then, the coils should come off reasonably easily. The primary should
be 0.2mm dia approx and the secondary around 0.7mm dia.

Paul-R

**Slider2732** · 07-05-2012, 06:56 PM

@boguslaw - i've taken apart probably a dozen approx 15" monitors and do concur that the wire is very tricky indeed. But, it really is quite tough enamel. If you find the very fine (30's gauge per strand wire) then that may snap, but they are usually within the 7 or 8 strand coilings. Otherwise, carefully moving along, with constant pulling will see it steadily unwind.
Main use, for me, has been for multi-filar coils in motor experiments. My speed up under loads videos etc have used that wire. Make each strand a slightly different length and it markedly improves the coil running properties..all the strands are already there, so the time you lose in unwinding from the neck wiring is saved in the experiment coil winding.
The older the monitor the easier it generally is. Same for the degauss coil black taping.

@wrtner - good points. Microwaves are sold as shielded, but i've always had my doubts and there are a couple of YouTube videos where people put Avramenko plug LED detectors in front of the glass and get them to light.
I agree about the effort for the Primary in MOT's, huge amount of about 12 gauge copper !
I guess if you left a working microwave as is and the experiment didn't work, you could always take out frustration by putting a damp cloth over the circuit and switching on lol
Yep, the PC cases would seem to offer a fully shielded solution, just that you can see a circuit in a microwave.
With a bare back panel on the PC case, that would have to be have a plate fitted (power supply hole, card slots etc). Heck, maybe cut a piece from another case

Would be good to make a comparison - perhaps a fun exercise for the original poster, to show us the differences.

**boguslaw** · 07-06-2012, 07:23 AM

Originally posted by Slider2732 View Post

@boguslaw - i've taken apart probably a dozen approx 15" monitors and do concur that the wire is very tricky indeed. But, it really is quite tough enamel. If you find the very fine (30's gauge per strand wire) then that may snap, but they are usually within the 7 or 8 strand coilings. Otherwise, carefully moving along, with constant pulling will see it steadily unwind.
Main use, for me, has been for multi-filar coils in motor experiments. My speed up under loads videos etc have used that wire. Make each strand a slightly different length and it markedly improves the coil running properties..all the strands are already there, so the time you lose in unwinding from the neck wiring is saved in the experiment coil winding.
The older the monitor the easier it generally is. Same for the degauss coil black taping.

"I have taken apart ~10 CRT TV's/Monitors and only have been able to salvage the wire on deflection yoke twice. Whey you remove them by breaking the glass or taking out each screw you end up with two coils, easy enough right? Well each coil 80% of the time is covered in some sort of adhesive or glue which makes them almost impossible to unwind with out breaking the wire.
"

From this page : 4hv.org: Printer Friendly

I fully agree with this comment.I had them mostly in such form : http://4hv.org/e107_files/public/130...ction_yoke.jpg
and found it impossible to separate single wire from this glued composition. Sometimes however coil is in form of multistranded wire - easy to remove such kind.

**wrtner** · 07-06-2012, 09:05 AM

Also worth taking apart:

printers and scanners:

stainless steel shafts for motor applications,
gears,
belts,
long thin optically high quality mirror (scanners)
heavy steel bed plates
heavy plastic plates
and PSUs offering odd output and potentially useful voltages.

Also, visit your local recycling centre. There is no saying what you
will be able to take away as long as you say that the items are
for spares only. You may get some 316L stainless steel from
scrapped medical equipment or commercial kitchen scrap.

**Slider2732** · 07-06-2012, 05:04 PM

That's one thing to remember on the monitor deflection coils...single strands won't come away, they are usually bundle wound, 4 to 8 wires as a multi-strand arrangement. I see how people would struggle to remove just the 1 wire at a time. Once off, they should be used as that bundle (not connecting any wire that is not needed on the finished project coil). It can be argued, that unused strands increase the running capacitance of the finished coil and is a benefit in some applications. Such that for a tri-filar that has 6 wires from the monitor, you would connect 1, 3, and 5 on the coil that was wound from it.

Say wrtner, do you know what type the scanner LED's are ? I have a couple of salvaged strips from scanners here and am having a heck of a time working out what they are. They're not I/R photodiodes it seems.
IIRC, a thin laptop type fluorescent moved across the item to be scanned and then the 80 or so LED's moved along underneath. But i'm getting nothing from any test of the LED's once removed from the carrying board.

**Mad Scientist** · 07-06-2012, 09:36 PM

How to make room for new stuff. Go through all the old stuff and separate it into to piles. One is for anything that still has use in its original form and the other is for stuff that is broke or obsolete and would never be used.

Then go through the second pile and dissemble everything saving only

**wrtner** · 07-07-2012, 02:33 PM

Originally posted by Slider2732 View Post

Say wrtner, do you know what type the scanner LED's are ?

They might vary. It might pay to get on to the individual manufacturers.

Also, there is a lens which might have value.This applies to CD drives.

**thx1138** · 07-07-2012, 06:56 PM

Many thanks

[QUOTE=This should give you a bunch of room that can now be filled up with new junk.

[/QUOTE]

Actually, I'm just trying to get enough room on my work bench to start a new project. To do that I have to get enough junk off the floor to get to the workbench to clean it off or build a new one. I haven't watched any of those "hoarding" shows on TV but I'm beginning to think I might qualify.

I'm kind of new to this but I'm wondering if there is some alternate energy physics law about horizontal surfaces and interstellar attraction of "stuff" so that maybe I could find the opposite law of repulsion of "stuff" from horizontal surfaces. I'm thinking it might have something to do with my wife but she's pretty sure I'm from some other galaxy anyway so that might not be related.

Any good tips and/or web sites on desoldering? I've got the normal suction devices, braid, and some different tips.

For salvaging components from circuit boards where I don't care about saving the circuit board itself I use a propane burner to heat a 3/4" thick piece of steel about 8" in diameter and use the temperature probe on my multi-meter to get somewhat above the solder melting point. I then put the board on the steel plate with the components up and the pins down to let the pins heat up, let it heat for about 30 seconds, and try to pull the components off with tweezers and/or forceps. Sometimes it works OK, sometimes not. Yes, I use a filter mask and face shield.

**Slider2732** · 07-07-2012, 07:35 PM

Good to hear of your safety measures. I became quite ill some while back when I ran out of solder, kept using the circuitboard bits and they weren't ROHS lead free !

Quick tips on desoldering.
Main thing - no more than 5 seconds of heat and use a 30W soldering iron, no higher. Lower wattage probably won't melt the solder.
One of the cheap Radio Shack irons will do just fine and in fact you might use one just for the purpose, as the end can bend with a lot of desoldering and pressure applied.
You can remove a lot with the tip of a soldering iron. For resistors, place a thin jewellers type screwdriver under the middle and gently lift as you work on the back of the board.
Glass diodes, like 1N4148 will come out in the same way (even fingernail instead of screwdriver) and they are tough. Many people seem to think they'll break, but only the larger germaniums seem brittle like that.
Capacitors can be gently rocked as you heat both legs, it's more difficult than may be imagined to pull a leg out of the can.

Solder braid is excellent for chips and sockets. if a chip has a socket and you want the socket too, pull the chip out first. A flat blade screwdriver will lift both ends up a little as you go and any chip will then come out cleanly.
The braid should go over just one leg, such that the leg itslf shows through the middle of the braid. Place
the soldering iron on one side and let it sit for 5 seconds, then quickly remove the braid along with the iron. You should have a clean leg. A tap with a finger left and right on the leg will see that it's free of the hole.

For large items like flybacks, with lots of solder...it may be best to use a Dremmel and cut out the circuitboard. That way, you know the pins are fine and can readily solder to whatever is there already.

**thx1138** · 07-12-2012, 11:45 AM

Desoldering flybacks

Good idea using the dremel tool. I've been using one of the diamond cutting wheels for sometime and really like it. Thanks.

**ewizard** · 07-12-2012, 02:33 PM

Regarding desoldering I like to go in with a high wattage iron like 150 watts or so. The less time heat is on something the less time it has to spread. So hit until it melts which with that iron may only be a second or two and yank it out. IMO a low wattage iron gives everything more time to heat up and yet it still has to reach a certain temperature to melt the solder. I usually use a solder sucker although I've found cheap ones are next to worthless. Good to see I'm not the only serious pack rat here

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