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Anyone re-purpose e-waste?

Chuck(G)

Chuck(G)

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Jan 11, 2007
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Pacific Northwest, USA
I'll confess that I hate throwing stuff out. My wife is something of a packrat too, so she doesn't mind my peccadillo.

At any rate, I've had this old UPS kicking around the shop for quite some time. It's an old unit that took 4 x 6 volt gel cells and claimed to provide 500W of backup power. At some point, it started blowing the low-voltage fuse, so I removed the batteries and stuck the unit in a corner, vowing to get back to it one day. Probably one of the high-power TO3 MOSFETs went bad.

The thing has an impressively large (22 lbs) transformer in it. Digging around in my other stuff, I located an old Variac and a couple of unused panel meters. Add a rectifier and presto--a low-voltage variable power supply. Coincidentally, the full-range output of the setup is 14.9VDC and it can deliver 30A without breaking a sweat--and that's exactly what I had meters for.

So, this is the result:

oKqWo3v.jpg


Anyone else do this sort of thing?
 
Yup, half of my project enclosures are cases from other things that have died or just became non-useful. I recently turned a linear supply into a rack-mounted replacement for 12V plug packs/line lumps for the rack-mounted gear:

http://www.glitchwrks.com/2016/01/03/rack-dc-supply

Much of my prototyping/hobbyist IC stocks come from desoldered scrap boards. Lots of good stuff to be recycled from eWaste!
 
Nice.

Yeah, I'm guilty of turning the hot air gun on old PCBs before throwing them out as well. Heat 'em up, give them a good sharp rap and collect the goodies that fall out.

Older stuff is generally more useful for that. I don't have the skill to repurpose BGAs.
 
In some people's opinion, collecting old computers and other vintage electronic devices could be considered as "repurposing e-waste"... :geek:

More to the topic, I've re-used the cases of broken electronic devices before. Several years ago, I had a small 12V DC power supply in a metal case which got shorted, and burned out its transformer. Several years later, I needed a cabinet to put a Powerstat 10 variac in, and discovered that the old power supply case was just large enough. Removed the old guts, drilled some holes, installed the variac and outlet in the front, installed a 1 ohm power resistor across the old terminal strip (in series with the output of the Powerstat, to allow for AC amps to be read with an AC voltmeter), wired everything together, and it worked nicely. A picture of it sitting on top of my R-390A/URR receiver can be seen below. It's on top of the receiver, underneath the Simpson 260 multimeter.
r390a_setup.jpg


I've done other repurposing, but that's the main example which immediately comes to my mind. I have other plans in mind, one involving turning an audiometer case into a synthesizer, and another involving turning an old "Digital Phasemeter" into a nixie tube clock. I prefer to preserve examples of vintage tech if I can, but otherwise, I at least try to put it to good use in another purpose.
-Adam
 
The problem with some old stuff is that it sits on a shelf.

Like you, I have an old CAY-46077 receiver (BuShips/Westinghouse) sitting on a shelf that I paired with an old Western Electric rackmount power supply. Works great--but I haven't powered it up in probably 20 years. Same for lots of old computer gear. The great thing about this old stuff is that it was built to last--not like our "recyclable" e-waste stuff of today.
 
I tend to rip useful parts off dead boards and power supplies before I toss them (or stack them for recycling).

Cooling fans from otherwise dead power supplies can be reused. AT keyboard plugs from dead motherboards (seems like when an old battery leaks it takes the plug out). RAM chips or cache chips get saved. The older HD's had some decent components on their controller boards. Cooling fans and heatsinks from dead gaming graphics cards. And any wall-wort power plug that still works. Even heatsink mounting brackets get saved.

I don't have a variable power supply around, I just keep spare PC power supplies if I need something to test with.
 
FWIW, the power supply above is mostly intended for (wet) battery charging and electroplating.

Another decent source of parts are old copy machines and microwave oven. I built my EZ-Bake tape oven using a lot of parts from a microwave. The only thing I bought for it was a PID controller.

This hails back to my youth when I used to cruise alleys looking for old radios and later, TVs. A TV power transformer was perfect for a small CW transmitter. You could even use the horizontal deflection amp tube as the final (usually something like a 6BG6G, glowing red plate and all).
 
One time I attempted to use a stepdown transformer from a broken desk lamp to power a microphone preamplifier that runs on 12 VAC. Unfortunately for me I somehow miswired the transformer and blew its thermal fuse. I kept it for a while as I meant to fix it, but eventually I just threw it out without even trying. I still feel dumb when I think of this as repurposing that transformer should've been an easy thing for me. I eventually just bought a transformer intended to power garden lights to power the preamp. At least it was cheap.
 
Chuck(G) said:
FWIW, the power supply above is mostly intended for (wet) battery charging and electroplating.

Another decent source of parts are old copy machines and microwave oven. I built my EZ-Bake tape oven using a lot of parts from a microwave. The only thing I bought for it was a PID controller.

This hails back to my youth when I used to cruise alleys looking for old radios and later, TVs. A TV power transformer was perfect for a small CW transmitter. You could even use the horizontal deflection amp tube as the final (usually something like a 6BG6G, glowing red plate and all).
Click to expand...
Do you get into electroplating often? I already have a car battery charger you plug into a wall socket.

My mother snagged an old toaster oven at a garage sale (its old fake woodgrain sides you could fit a turkey into, solid heavy metal). The old lady who owned it had connected it to a thin extension cord and melted both cords together (so its decent wattage). I installed a heavy duty cord and was thinking of using it to bake video cards with bad solder BGA. Think I still have a couple old (90's era digital programmable) high end temperature controllers around with ramp soak settings I could use for precise control. Just never got around to it.
 
Yeah, I do, mostly copper and silver; some nickel; a nasty business involving nasty chemicals. The trick is to regulate the current-per-plated-area, which is what the variac is for. In the case of silver plating, the voltage is only about 2V.

Sounds like the toaster oven and controllers should do the trick; I've certainly read about similar setups.
 
At work I have saved two plotters from the trash. Government agencies can sure be wasteful. There was nothing wrong with either unit. One was being replaced with a newer model. The other was a combination plotter/large format scanner (Designjet 800 series) where the scanner part broke. I grabbed the plotter part, but the scanner got trashed before I was able to get it. It likely could have been salvaged too, I suspect the hard drive died on the attached computer console and just needed to be fixed.
 
Chuck(G) said:
Yeah, I do, mostly copper and silver; some nickel; a nasty business involving nasty chemicals. The trick is to regulate the current-per-plated-area, which is what the variac is for. In the case of silver plating, the voltage is only about 2V.

Sounds like the toaster oven and controllers should do the trick; I've certainly read about similar setups.
Click to expand...

I worked at a plating shop for a while after college. Copper and Chrome plating. They did industrial cylinders for the printing industry where they copper plated a huge cylinder, used a diamond needle to engrave the design, then chrome plated it to keep it from getting damaged. They also had a huge printer to make proofs for signoff before shipping. Was cool looking at the designs for foreign cigarette packs plus the more common ones for stuff like boxed soap etc. The chrome stripper (if the proof was bad) was nasty and the cyanide strike tank could be deadly (used for aluminum cylinders when most were steel). Not a job you want to have for life but I seen worse.
 
Mostly, the copper plate (which doesn't involve cyanide, thank heavens) is an acid process, so if you don't mind handling sulfuric acid, it's not bad. Very useful for building up worn parts to get a snug fit. Follow up with a nickel strike and you're nearly as good as new.

What I mind the most is the buffing. Living in a dirty cloud.
 
I re purpose old stuff all the time. I've lost count how many computer power supplies I have modified (i.e. added terminal poles or flying leads etc) to create high current +12 and +5V sources. It saves me paying ~$100 for decent 15A switchmode power supplies for the odd project requiring it (i.e. 3d printer power supply, battery chargers, amplifiers etc).

I've also dismantled a lot of old scientific equipment which was destined for E-Waste (I work in Chemistry research). All of the components used are top quality and certainly built to last. Got plenty of knobs, switches, transistors, connectors etc from that. I have also got a lot of vintage computing stuff too; most people just throw it away because its 'old' or something simple has gone wrong and they don't know how to repair it. The best thing I have gotten so far is an old control box from a demineralised water plant. It has a heap of 60's valve based circuity to determine water conductivity; fluid level in tanks and system automation (i.e. turn on the plant when the tank is low, transfer between storage tanks, turn off the plant if the conductivity is too high etc). Best part is it worked flawlessly from ~1962 until the plant was replaced in ~1996 and was never turned off. Hung on the wall for ages after that until renovations this year which repurposed the room. I was lucky to know the builder who was in charge and he called me up one day saying it was destined for the trash. Since I have a lot of fond memories using that thing I jumped at the chance. The demolition guys were a bit rough with it when removing it from the wall as one of the panel meter glass screens was smashed but other than that it was still in fine working condition. $5 at a picture framers to get a replacement glass panel and it's good as new. I plan to use it for water level measurement in my rainwater tanks and perhaps some conductivity measurements.

Same goes for my other hobby which is rebuilding/repairing cars. I have a huge amount of spares from a lot of different models/makes which I have picked up from the self serve junkyard over the years. Once a year I also buy a car from the junkyard complete for ~$500USD and fix it up. Most of the time the faults are quite simple but people just give up on them. For example I got a BMW E34 5-series for $900USD. Bodywork was perfect; all that was wrong was the starter motor had failed and the transmission cooler had a leak. Fixed both problems for ~$100 and had a perfectly driveable car.
 
Chuck(G) said:
What I mind the most is the buffing. Living in a dirty cloud.
Click to expand...

I occasionally buff chrome parts for motorbikes on a proper series of fabric wheels. When you say dirty cloud you are not wrong.... I certainly would not like doing it for a living.
 
I do this kind of thing. I'm eventually going to build a home-brew computer that has a keyboard cable compatible with the TI-99/4A, so I can reuse my trashed TI-99/4A case. I also plan on putting a Raspberry Pi in an old Sega Game Gear case, and making a synthesizer with the old TI-99/4A sound chip.
 
I've pulled computers out of the trash, put new motherboards in old cases and re-engineered older computers to do things they were never capable of doing. I only throw it out if it's completely useless. Current computer is in an old Area 51 case: lots and lots of ventilation!
 
As already mentioned, old PC power supplies are excellent to repurpose for other projects. I prefer modern server supplies to the old AT boxes as they have very compact cases, although their smalller fans are usually much noisier.
From old modems the LEDs can be saved as a strip of half a dozen or so of the same colour, are already neatly spaced apart, and they have the current limiting resistors right next to them on the circuit board. Just cut the board 1cm or so back from the front edge to retain the resistors
Old photocopiers (and laser printers) are a gold mine of electromechanical parts, the older you can find the better. Shafts, gears, motors, solenoids, rubber feet, photointerrupters, connectors, grommets, IEC socket (often with line filter or DPST switch) and more. And if you're lucky the glass might be a real glass plate. This is optically flat, already has bevelled edges and makes a wonderful surface plate for model engineering if the marble or cast iron ones are too expensive for the amount you intend to use it. I put a piece of cloth on the workbench, place the glass plate on that (stops it rocking) and use a surface guage (example http://www.micro-machine-shop.com/height_gage_scribe_2.jpg) for accurate marking out of all sorts of projects.
The cases of old PCs is a no-cost source of thin sheet metal (plated or passivated one side, painted the other) and has 90 degree bends ready to cut brackets from.
I've used a photodetector from a broken VCR to repair a toy, and some people have used the VCR timer with tape load motor assembly for automatic aquarium feeders.
There are lots of things to repurpose from e-waste!
 
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