Introduction: Harvesting Electronic Components

Picture of Harvesting Electronic Components

With stores like Radio Shack disappearing, it is getting hard to find simple electronic components. The web, particularly eBay, has been a great help, but shipping can get costly. Consumer electronics, like VCRs and Microwave Ovens can be a source of parts, but consumer electronics tends to very highly integrated. Many parts are special made, or so specialized they are not useful.

Lately, however, the recycling move has produced a wonderful source of high-grade electronics. Check around you area for electronic recycling centers. These businesses take electronic equipment from companies and take responsibility for bring the material into the recycling stream. They typically disassemble the equipment separating the various metals and other valuable contents into various bins for sale to refiners. The circuit boards get thrown into a large container and are usually shredded for reprocessing.

Commercial equipment is built to a much higher standard than consumer electronics. Cost is not so much a factor, and since the volume of production is lower, they tend to use standard components.

One large recycler in Houston charges about $1 a pound for circuit boards, but quite often just gives then to me when I tell them the boards are for our makerspace. Another place I've been to seems to be glad to see the boards go. He has never charged me for a used circuit board.

Step 1: Selecting Boards for the Harvest

Picture of Selecting Boards for the Harvest

Be picky when selecting boards, remember you will need to dispose of the waste properly. It depends on the type of prototyping you will be wanting to do. You may want only through hole components, or maybe you would like to experiment with some surface mount components. I tend to look for board with a lot of analog circuitry. The board above is excellent. It has some digital logic, but it has quite a few high quality op-amps and trim-pots.

Avoid boards that are conformal coated. These boards have a tough coating both front and back and the part are very difficult to remove. Conformal coating is common in surplus military boards

Step 2: Some Tools You Will Need

Picture of Some Tools You Will Need

A metal tray is great for catching the parts as they come off the board. Since we will be using a good bit of heat, a welding glove is good to have. Other holding tools such as small vises, vise-grip pliers. and board holders come in handy. Don't forget eye protection, the wrap-around safety glasses are best.

Finally, you will need a heat source. I use a small butane torch, big torches are too hard to control. Also a high-temperature heat gun works well.

You need anything that works well at grabbing the parts. Needle-nose pliers, IC pullers, slip-joint pliers, and hemostats work well.

Plan to work outside with a light breeze. You will be hitting the circuit board with a lot of heat, so fiberglass will be burning and smoking a bit. Eye protection is a must. Bit of hot solder will be flying about.

Step 3: Getting Started

Picture of Getting Started

Examine each board and plan a strategy for the board. Be sure to remove any fasteners that are securing components. Plan to work on the parts that are easiest to remove first. Many straight legged parts fall right out when heat melts the solder. Some components, such as resistors, are crimped on the board before the board is soldered. It's best the leave these behind.

Step 4: Easy Parts First

Picture of Easy Parts First

Heat the board gently and as evenly as possible under the component you wish to remove. Some components will just fall out of the board once the solder melts. I tap the board against the wooden bloc to help jar part loose. Get as many parts off as possible using the heat and tap technique.

Step 5: Smaller Parts Can Be Removed With the Needle Nose Pliers

Picture of Smaller Parts Can Be Removed With the Needle Nose Pliers

Try the needle nose first. Clear out the small capacitors near the ICs. Needle nose pliers also work well on the 8-pin DIP packages.

Step 6: Remove the Larger ICs

Picture of Remove the Larger ICs

Slip-joint pliers work well for pulling ICs off. ICs are usually not crimped, but there leads are bent outward to hold then in the board while being soldered. Wiggle the IC and it will come loose, almost like pulling teeth.

Step 7: Give the SMT Parts the Brush-Off

Picture of Give the SMT Parts the Brush-Off

SMT parts can be removed with a small needle nose. Another way that works well is to brush them off the board with a disposable acid brush. Heat the board from the back and keep the brush moving. As soon as the solder melts, the parts will brush off and fall in the tray.

Step 8: Cleaning Off the Board

Picture of Cleaning Off the Board

After a few minutes, you should have almost all the parts off the board and in the pan. Notice I left the resistors. These were all clinched to the board and simply not worth all the effort it would take to remove them.

Step 9: Big Pile of Parts, Now What?

Picture of Big Pile of Parts, Now What?

In the photo you see the result of harvesting two circuit boards. Now it's time to sort the parts and look up those you don't know. Thanks to the Internet, finding data on most of these devices will be easy.

Surface mount ICs can be difficult to catalog. SMT resistors are usually marked, but capacitor are not. I use a DER EE DE-5000 LCR meter to test and sort capacitors. It works great and comes with a tweezers type probe for test SMT componets. They are about $140 from eBay and Amazon suppliers.

Happy Hunting!!

Comments

Man Up (author)2017-07-20

I have two major criticisms of this 'ible.

First, this method of heating up the solder puts as much heat into the component as it does the joint itself. A butane torch can concentrate well over 2,000° F onto the surface of the PCB, and the component will sink several hundred degrees through the pins and into the device being removed. Most components fail when exposed to temps over 350° F. Your fingers will barely register much heat in such a small area, but the internal junctions will be toasted.

The proper way to remove components is through the use of a soldering pencil of between 25 and 45 watts watts, a desoldering device (either a 'solder sucker' or preferably a high quality copper braid "solder wick"). For components with multiple connections, a clamp-on heat sink (you can make one from an old heat sink and a binder clip) should be used to protect the component from excess heat.

Secondly, there is that there is no mention of ESD precautions. Anyone who has ever walked across a carpet in winter then got the dickens shocked out of them understands the idea of static electricity. But even when the air is humid, we can still carry several thousands of volts of electrostatic charge on us. This static charge perforates the thin metal oxide layer that most modern semiconductor MOSFET devices utilize. Precautions might be as simple as using a cheap $2 grounding strap, or they could involve layering your work area with a rubber ESD mat and grounding everything.

Please, please include some discussion of these two items. I appreciate that you're promoting recycling (I personally have saved $80 in the last month salvaging rando IC's and micro-relays form PCB's I dug out of the trash at work), but for someone getting started in the electronics hobby, this can add to their frustrations.

Fusepopper (author)Man Up2017-08-23

I second the motion of using "copper braid solder-wick." The stuff is pretty olde school and many people don't know what it is anymore, but it works well (especially the wider, thicker stuff) for sopping up the solder off the board before you pull the components using any heat source - and to me (being too cheap to have a temperature-regulated soldering station) it's indispensable for everyday soldering, getting into places a solder-sucker can't. It's impregnated with rosin to make the old solder flow better and "wick up" onto the copper braid by capillary action. Comes in varying widths and lasts a long time.

geotek (author)Fusepopper2017-08-23

Soder-wick works well for removing single components, but it's too expensive and tedious to use for cleaning off an entire board. The small butane torch produces a gentle flame that is much like a heat gun. The heat is spread over a large area and components release as soon as their solder melts. So the exposure to heat is not much greater than the melting point of solder. If you have ever worked with flow solder machines or reflow ovens, you will get a better idea of how much heat electronic components are designed to go through. It's amazing.

RayW52 (author)2017-08-14

I did it with a craft knife and some pilers. Really messy, as you have to cut the solder carefully and not slice the component in half.(My parents won't get me a solder iron or any other heat source in fear of setting our home on fire).

KimS11 (author)2017-07-20

This is a really well written/constructed article.

Ive spent 40 years building electronic devices...from Tubes up to current technology BUT I dont use recycled components now (and I know Im going to get screamed at for this by other users).

I feel that I spend hours if not DAYS designing, prototyping, and building circuits, and the worst thing that can happen is that I have a duff component that makes me take more hours, or days to find. Considering that I can get a kit of hundreds of every value of resistor, capacitor, electrolytic imaginable, for only a few bucks on EBay, and get specialty components, often for a few cents each as well, all for free shipping.

When I was 8, and a 2n2222 was 5 bucks each and a pack of 5 resistors was $1.50 (a ton of money considering a candy bar was 10 cents, and a comic book was 10 cents), I would spend hours desoldering components, of which many would be damaged by the heat. Now that Im 55, I just dont have time for this.

One thing that I dont think was mentioned are the REALLY DANGEROUS TOXIC FUMES that can be given off by heating up components/boards.

PortlandGirl (author)KimS112017-07-20

Unless the boards are coated or you're melting the plastic, the only fumes you should have to deal with is from the flux, which isn't toxic. Just basic solder fumes. And if the board is modern, it will be ROHS anyway, and use lead-free solder. But I (and most I know who have been in electronics for decades) never worried much about solder fumes. I'm not aware of any epidemic of technicians getting sick from just them. It's always been from exposure to OTHER industrial chemicals that are actually toxic. Just wash your hands if touching the leaded solder.

preschau (author)PortlandGirl2017-07-20

Exactly. I've been soldering professional and consumer electronics for nearly 60 years most of it with leaded solder with no protection or serious effects unless you would consider a bit of arthritis to be caused by lead/flux poisoning.

It's only recently I knocked up a little fan out of a 5" computer fan to remove the fumes as they were effecting my old eyes.

gomibakou (author)preschau2017-07-21

Because you don't have any side effect it doesn't mean it's safe. Surely your body didn't accumulate enough lead. The problem with lead is that, once it's in your body it remains forever and reaching the critical ammount the effects appear. It's well known the lead makes changes in the brain structure and affects the neurogical connections

I know welding professionals with no problems at all, and others have serious issues in their eyes (due to the welding light/radiation) and lungs, both using the proper safety equipment. The former will say it's not dangerous because they don't have anything... in the same way the politicians say paying more taxes is good for the country, omitting they earn 3/4 times more than average citizen and pay same or less taxes.

Fumes are bad, simple. How do they affect the person, it depends on the person, exposure time, kind of job, etc... but they are bad for you health.

ed-romes (author)gomibakou2017-08-08

Old time plumbers used melted lead all the time !! Have you ever heard of them having lead poisoning ?? That smoke is not lead its the Rosen/flux thats used to make the tin/lead mix stick to both the copper pad on the board and the wire on the part !! And as he was using a torch to heat the solder to melting point he was also burning the board which is made of toxic materials !! Thats why he said do it outside !! And I've done this kind of stuff for over 54 years and I'm 59 and so far no medical test have shown any lead in my body and lead was in the gas , paint and plumbing for most of those years !!

preschau (author)gomibakou2017-07-21

>Gomibakou

As someone else noted, when soldering the temperature isn't high enough to vaporise the lead in the solder so it can't be a problem as far as breathing in the fumes. As Portlandgirl pointed out what you're breathing is burnt flux which is pretty well harmless in the doses one normally gets.

Any lead poisoning one would receive would more likely be absorption through the skin from handling the solder and as far as I aware that's never been a problem.

Like most industries there have been many toxic chemicals used in the past in electronics and when it became apparent that they were dangerous they were withdrawn. Carbon tetrachloride, Xylene and Barium based heat sink compound are some that come to mind.

I'm not sure what welding has to do with this.

t.rohner (author)KimS112017-07-21

I used to do this as a kid as well.

Here in Europe it was the BC238 instead of the 2N2219... but also expensive in the seventies. Nowadays i get most of these parts new for a couple of cents. A friend of mine works in a production facility for industrial electronics. He can tell horror stories of failing parts, thanks to the higher temps used in leadfree soldering. If you add two more heating cycles by unsoldering and resoldering, the thermal stress might be too much.

Considering this, i wouldn't use salvaged parts for "vital" stuff.

rhllngwrth (author)2017-07-21

I agree that you should not breath the fumes in using the torch method, Plastic and resin vapors are not healthy. As for the lead, it is the ground water contamination concern, used junked electronics leaching lead into the ground water. Same issue caused the replacement of lead shot for duck hunting.

I have salvaged electronic since my teen years also, used them to experiment and in Ham Radio projects. Resistors, elec. capacitors are usually not worth the effort. I Look at the old TV sets, computers and monitors. Many are put out on junk day. I get heat sinks, chokes and transformers, power MOSFETS, pots. There are pounds of copper in old tube sets around the picture tube (yoke coil) that can be sold. We see many old flat screen monitors that do not light up. Replacing the capacitors that drive the screen can restore them. A second monitor for you computer on the cheap. I have salvaged several for this purpose.

Transistors and ICs are heat sensitive, the torch method could cook them, I use a temperature controlled soldering iron, vacuum type de-solder tools. Solder removal wicking also works. Identify the parts before you remove them to save time, determine if they will be useful. Larger Electrolytic Capacitors from old radios can be valuable provided they are not gone bad, used in power supplies from TVs, Monitors. Check for swelling or leakage. Ceramic caps do not fail often. Larger sized caps and resistors for higher voltage can be useful.

Danger, if you collect to much salvage, you may become a hoarder.

ed-romes (author)rhllngwrth2017-08-08

For over 50 years I've known how to harvest electronics and back then they knew how to make power capacitors if one didnt hold a charge for at least a year it was faulty and needed to be replaced !! And then there was the vacuum tubes harvest them and. Test them if they worked lable a box with that number and put all tubes with that number into it you had audio tubes and voltage control tubes video stabilizer tubes !! Transformers for stepping down voltage and up its sure was I pain if a 25000 volt cathode wire discharged into you as you disconnected it from the CRT/pitcher tube !! Back then they left enough pigtails on the resistors so you could cut them free !! To bad they dont build things to last anymore !!

I love amateur radio projects almost as much as getting on the air!

73 de AA4PC
(Ham Radio=hoarders)

leryis (author)rhllngwrth2017-07-24

Hoarder, oh jesus yes

alaafprojs (author)2017-07-20

Cool I like the idea

also I am SOOOOOOOOOOOOO upset that RadioShack is going out of business :'(

PS: one of the employees told me that iPhones "Killed" them

ed-romes (author)alaafprojs2017-08-08

Sprint killed Radio shack after they bought them !! And instead of closing sprint stores that were failing they shut down the shack !!

Did he explain how the iPhone put them I of business? I guess I don't understand the connection

They used to sell cameras iPhones are cameras (he gave some other reasons to but I don't remember them

I would have to say that what has hurt them the most is Amazon. Having the ability to order large quantities of electrical components from vendors vying for your dollar has most likely taken a huge chunk of RS market. Not to mention that RS used to carry the latest technology, but the internet and Amazon has brought that market to your fingertips. Low prices and 2 day shipping are such a great deal that even Walmart had to follow Amazon's lead. Barnes' and Noble, along with most other chain bookstores have had to close down because the business model doesn't work due to the high overhead. Best Buy can still compete because people want to see or "check out" many of the items they sell prior to purchase.

Don't get me wrong, I love Radio Shack. The other day when I needed thermal paste that day to get a CPU back up and running, my local RS was there to save the day. But all things considered, the music lyric "video killed the radio star" can be reapplied here: "Amazon killed your local store."

KeithT66 (author)Benaiahwannabe2017-08-02

I miss radio shack , that was the only store i could buy a great sortwave radio at and i build radios myself , my first radio was a crystal radio i built from a kit i bought from radio shack ,

I see you calling the store Radio Shack; am I to presume from what you say they dropped the name "The Shack"? The only local or fairly local stores that carried a lot of electronics parts were owner run and not corporate. I heard they hadn't closed *all* the stores; but, I can't find them here in South Carolina anymore.

I agree

RobPaige (author)Benaiahwannabe2017-07-28

It wasn't the iPhone specifically so much as it was cell phones in general. Corporate leadership focused on that to the exclusion of pretty much everything else. When AT&T launched the iPhone, you could only get them at AT&T corporate owned stores, so we'd have try to convince you that what you really wanted was a Palm device or (god help me, I'm not kidding) a Windows phone. When Android launched, that helped, but the damage had been done. Even finally being allowed to sell the iPhone came too late to reverse their decline.

They specialized in iPhone, which has a narrower market and so less sales. They expanded into other phones, but it wasn't enough. Plus, I know I wasn't the only one going there to try and find the things I could have found in the old Radio Shack before it became The Shack. I would complain to the manager, who would just reply it's a corporate store and they sold what they were sent. So, more an more phone were trying to be sold, along with every mom and pop store in the city. Instead of being a market leader they were just following the pack, and they couldn't compete especially in a declining market. It's as simple as that.
Here's 'a' link: https://www.theverge.com/2016/6/1/11836816/iphone-vs-android-history-charts

Cyberchipz (author)alaafprojs2017-07-21

FWIW I even called the corporate offices and warned them. lol What a waste of my time. I said we wanted the old Radio Shack back, and that they'd forgotten the tinkerer. The parts that The Shack carried were abysmal.

RobPaige (author)Cyberchipz2017-07-28

I worked at a store that served a lot of farmers, it killed me to watch as corporate gutted our part and tool selection.

leftywi (author)alaafprojs2017-07-20

Radio Shack went belly up because they gave up on the hobbyist DIY people. By the time they realized the insurgent it was too late.arduino and Pi for example

Cyberchipz (author)leftywi2017-07-21

leftywi Absolutely! You're totally correct. That and the lack of foresight in the corporate administrators.

GTO3x2 (author)leftywi2017-07-20

True, but there's more to the issue than simply that; I do miss the availability of elemental parts. MicroCenter has lots for a hobbyist that are more than elemental parts. DigiKey seems to accommodate even the small orders; I wish they'd ship the very small orders via USPS.

Phildem (author)2017-07-20

Hi, DO NOT USE Flamme, use hot air, Flamme is toxic and will make very bad result

Antony76 (author)Phildem2017-08-03

+1
Use hot air gun instead.

Gelfling6 (author)Phildem2017-07-21

The flame from the torch is not what is toxic, but the fumes from burning phenolic (the old style PC boards), Epoxy-resin, and yes, even plastic. this is why he said, in the instructable, doing it OUTSIDE, with a breeze to carry the majority of the fumes away. Hot-Air will also cause the materials to burn just as much.. A 'SMT Re-work' station is a little more targeted (a 1/4"-3/8" square or circular tip version of the popular heat guns), but still just as capable of causing scorches and burn spots.

Phildem (author)Gelfling62017-07-22

Hello, okay but after more than 40 years of practice of salvaging components, I tried many technical and HotAir gun is very superior, it's more easy to control the heat and I guess less nociv. The best is to try different technics to find the best.

Cyberchipz (author)Phildem2017-07-29

I agree Phildem, the heat gun is superior as it allows for a more controlled heating, the real issue is between surface mount, and through hole mounts. Either way, adequate ventilation is always recommended. And I think it goes without saying that if one uses a concentrator on the tip of a heat gun, there's some loss of control. Naturally, common sense is the order of the day; IOW, we're only wanting to heat up the soldier, not everything else.

Antony76 (author)Phildem2017-07-20

+1

RobPaige made it! (author)2017-07-28

Salvage from a motherboard, card reader, and dialup modem from an old computer.

throbscottle (author)2017-07-21

Anyone know where I can get scrap boards like this in the UK?

Thought as much. Didn't realise it was so strict. I'll stick to kerbside and skip finds...

The EU directive is called WEEE (Waste Electrical and Electronic Equipment). Larger dealers are required to provide a facility for you to return similar equipment to what you bought, for recycling. Also covers commercial stuff but I don't know how that side of it works.

agulesin (author)throbscottle2017-07-24

I think the UK is covered by some many (too many?) EU regulations that boards are 'locked' into a recycling system - it might be difficult to get them except from small firms who are willing to let one or two drop off the system.

I'll ask at work; we scrap old UPS and have lots of boards with useful stuff but they are collected by companies who give paperwork to prove they've been scrapped according to the regulations... :-/

Roll on BREXIT is all I can say!

Raphabaz (author)agulesin2017-07-26

It's the same here in switzerland. Old electronic devices can be returned in any shop that sells electronics. Often the junk is locked to prevent dealers "steal" anything that can be selled again. From the collecting points they go into a closed recycling system controlled by government (respectevely delegated to private organisations who sell working devices independently..). Most recycling collection points let you pick out devices for a while. I used to pick out devices at a big seller for electronics and found running devices in original packaging (it's a shame - but my luck). Another option is telling your friends and family to call you first when something is to be disposed of. I prefer the "Identify and remove individually method" by solder iron, vacuum desolder pump and desolder braid.

21m0n (author)2017-07-26

for smaller components, like SMD, you can use a 100W bulb:

https://hackaday.com/2016/12/23/halogen-lamp-abused-for-desoldering/

John T MacF Mood (author)2017-07-25

Want to vote you up, but it's glitched and won't recod my vote!

John T MacF Mood (author)2017-07-25

Glad you make note of avoiding hazardous fumes & other vagaries. Some caps need shorting, and unless I didn't read thoroughly enough, I'd add that once. I had an old CRT TV that had not been powered for over a year, and it had one heck of a charge on it still. I managed to safely discharge it, and I'm glad I did. It lit up the room when it discharged! Greast work showing your tecgnique, great job!

ukdiveboy (author)2017-07-25

This is how we got all the ICs for my highschool technology class! It was 30 years ago, and in our poor northern town we could never have afforded all those TTL chips, had we needed to buy them! Happy harvesting!

Michal Choma (author)2017-07-25

The problem what I see, is if parts works, and will be working after some time. Like I have resistor from scrap. It can be good, I can measure, but after some time it can degeneration (be bad). Maybe coils or such things.

Wrrr 10-G (author)2017-07-24

Thanks for this, Geotek.
Never thought of daring to use a flame for a nice desolder 'shotgun spread' :D
Are the ICs still usable after that heat treatment?

JohnC430 (author)2017-07-23

after reading many comments, it looks like what one person said about heating the board from the back and letting the parts fall into a box sounds like a good idea. also sand in an old frying pan is the most effective and quickest way to remove parts. also quick and easy.

JohnC430 (author)2017-07-22

at first i thought. why would I? then i m bored so lets check it out....

and then i discovered...what a fantastic idea! thanks for sharing.

linuxdummy (author)2017-07-22

Good instructable. Many years ago when about everything was through hole, a electronics salvage that I visited a lot used an electric frying pan filled with think it was glass beads, maybe sand and placed the boards on top of the beads/sand and picked the pieces off. I was always going to give it a try but never got around to it. They could recycle the solder as it sunk to the bottom of the pan and could be poured out.

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