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Picture of Salvage surface mount components
I shall tell you how I rescue components from old circuit boards and store them for reuse. A board from an old (relatively new, that is) hard disk drive shall be shown for an example. The photo (taken using my scanner) shows one such board, after I removed the IDE connector.
 
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Step 1: Desoldering

Picture of Desoldering
I have a movie showing my process. I am attacking a tantalum capacitor in the video, but the same process works for all other components too.

First bend a piece of thick copper (or other solderable metal) wire to fit around the component, and contact all its solder pads. Solder it in place. This is done to make thermal contact.

Then heat the wire at a central place with your soldering iron, and lift the component away with tweezers. Or push it away using a wooden toothpick. Only don't be too enthusiastic with the push or it will fly across the room and be lost forever in the crud that covers the (in my case anyway) floor.

These are best stored inside foam cutouts in a suitcase. Miniature, of course.

Step 2: Tantalum capacitors

Picture of Tantalum capacitors
These are the electrolytic capacitors usually found on surface mounted boards. They have to be connected the right way round. The positive terminal is marked with a band. If there are two numbers on it, one is the rated voltage and the other is the capacitance.

I'm sorry, I do not have further info on identifying them other than checking them in a multimeter which has a capacitance range.

They usually look like little bricks with metal strips issuing from their ends, folded over the bottom.

On the left of the picture are ceramic capacitors - MLCs - short for Multi Layer Ceramic - usually they are this brown colour, though I have seen black and white, and the ends look as if dipped in metal. There are usually no markings at all, so measurement is the only way to classify them.

Step 3: Ceramic Capacitors

Picture of Ceramic Capacitors
Ceramic Capacitors look like bricks dipped in metal at the ends. The usual colour is brown.

Ferrite beads (or inductors) look almost exactly the same, exept that these have continuity and are magnetic. And black.

The photo shows a bunch of ceramic capacitors, and a few inductors (lower left).

If you aren't confused already, there is more to come.

Step 4: Resistors

Picture of Resistors
In contrast to capacitors, resistors are easy. They are usually white on the underside, black on top and have the value printed on them. The last digit is the number of zeroes. The first two or three digits are the figures before the zeroes. In ohms.

560 means fifty six ohms. 561 would be five hundred and sixty ohms. 564 would be five hundred and sixty Kilohms, or, more concisely, point five six Meg.

These are also seen as arrays, pictured here are 33 ohm arrays I soldered together because I did not find any use for them.

When kept loose in a box, they tend to obey Murphy's law and all of them will be hiding white side up. And the one you want will be the one you turn up last.










Because when you find the one you want you stop looking.

Step 5: Storing resistors

Picture of Storing resistors
So the easiest method of storing chip resistors is this one, which I have developed after much experimentation.

And countless times fighting against the urge to flush the lot down the toilet and forget about it and do something worthwhile, like watering the plants.

And saying hello to the wife and kids.

Take a piece of transparent plastic, arrange the little buggers face down on it and, suddenly, while they are least expecting it, place a piece of sticky tape over them. This holds them immobile and you can look over them leisurely, identify the one you want, then peel back the tape and lift off that one with tweezers. The others will remain stuck to the tape.

Step 6: Diodes, Transistors and ICs

Picture of Diodes, Transistors and ICs
Diodes and transistors generally come packed in the SOT package. This is the "small outline transistor" package, with three leads.

So a device with three leads sitting on the board might be a diode. It might be a transistor. Or it might be an integrated circuit, like a three terminal voltage regulator.

A bit of probing with the multimeter (hold the thing down with a croc clip) will usually tell you whether it is a diode, or npn or pnp transistor. Small canisters could be used for storing them.

A thing with many legs is usually an integrated circuit. Or a resistor array.

I find that using a vintage IC involves poring over data sheets, finding components, and much design work, and that the end result is some gizmo which does some ancient job poorly, which is why that board ended up in the junk. The effort is just not worth it. But I do keep the ones I remove, because they might come handy one day - to build into a sculpture perhaps.

So - start desoldering, and have fun.
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neelandan (author) 4 years ago
This the method to use when you need to extract just one component from a circuit board. It complements the "Bulk extraction" methods of using hot air or a toaster oven, because extracted components are a bit fiddly to handle and store for later use.
jparis12 years ago
try sticking the small resistors to a piece of elec. tape or duct tape right side up. no more hunting, when u want one jus use tweezers to get it off the tape. jus a lil tip, might help u guys.
eric m6 years ago
IC's are such a waste. I wanted an led display and chip but you know the chip is impossible to figure out. just a waste. Ofcourse component makers don't want a used market undercutting them.
The main consumer of parts in not hobbyists anyway, but factories. The reason the ICs can be so difficult to work with is either because they are cheaper to make that way, or the particular pinout order was easier to connect to some other specific chip without crossing races or stuff.
AJMansfield2 years ago
What about sub-ohm resistance values?
tanmanknex5 years ago
isn't the one you want always going to be the one you turn over last? why would you keep looking after that? jk ;D
So that you can find the one you don't want.
AJMansfield2 years ago
Just google search "capacitance markings" for more tables than you could ever possibly need.
TzarIgor2 years ago
To find more information about coding SMD-components read the book Turuta E., Turuta M. C. SMD-codes. Active SMD semiconductor components marking codes.
And then you can download apropriate datasheet from  http://www.datasheet4u.com
I use thise steps and save a lot of money while making a lot of gadjets from old electronics! 
zaphar3 years ago
I'm interested in salvaging ICs and whatever I can for educational projects, however, which parts are worth saving. The ICs seem like a no-brainer (at least the ones that have datasheets) but what about other components? I think I read somewhere that some SMD components are not worth salvaging due to lack of information on them (no datasheets or info). Could any knowledgeable individuals chime in on this?
so how do you remove those IC's with 5000 pins?
You can use a paint stripping heat-gun if you don't have access to a solder reflow workstation. It worked fine for me until I got mine a few months ago :)
what about a toaster oven, i have removed components off a board with one (accidentally) but it is reliable? and what it a solder reflow workstation?
sorry for very delayed response,
its a hot air gun for working with surface mount components.
Terrean3 years ago
A correction needs to be made in your Instructable.
A 564 resistor is actually 560,000 ohms(560 Kohms) and NOT "five hundred and sixty thousand Kilohms".
neelandan (author)  Terrean3 years ago
Edited to "560 Kilohms".

Thanks.
robonut6258 years ago
The Iron Is Genius!
thanks for the clothes iron video! i just have a crappy soldering iron and i think the clothes iron trick will do nicely!
That clothes iron video is amazing. Thanks for sharing it.
Genius!
SinAmos4 years ago
I love you. Good work.
zack2474 years ago
ive found a partially successful way to remove SMD leds with no chance of melting them and a small chance of breaking/losing them is not with a soldering iron, but a small exacto knife.

just slce under the LED and it will slide off the board with the knife, but dont put too much pressure on the knife or else you will either hurt yourself, other components on the board, or the surface you are working on.

i used this technique and out of 14 blue leds from a cell phone board, i got 10.
the other 4 were lost among the floor that happens to match their color.

i lost a few while learning to solder them, but it was a learning experience for getting them off, and it does wirk with patience.

i usually store my smd components in a small plastic bag (like you get those perfboards in @ radioshack), but a better storage method will have to be in order since the bag has a few holes in it.
The easiest way is to lock the board on a vice. Use a heat gun at high speed on the backside. Slowly remove the components with tweezer or needle nose pliers. Store components on an aluminum surface to cool fast. 99% of the components are good and reusable. Use google to look up datsheets for IC's. Then organize components by type and size. I can strip a motherboard in 3 minutes this way.
zack2475 years ago
how to do leds??? wont it melt from the heat?
aha! so that is an old harddrive board!
"so that is an old fujitsu harddrive board!"
zack247 Derin5 years ago
ahh... i have 2 dead fujitsus, they were very good quality if you ask  me...
eric m6 years ago
nicde. marx generator
eric m6 years ago
nice
altomic6 years ago
-big pot -cooking oil -stove -scooping net thing. put pot on stove add oil turn on stove when it it super hot throw in your pcb. stuff will melt off. IC are made to withstand hightemperatures. solder will melt before there is damage to the IC. scoop out IC with skimmer thing. party on.
Are there any noxious fumes from doing this? Will I still be able to get regular resistors from this or willt hey melt? Will anything bad melt? Do an instructable on this please!
plastics might melt
geeklord6 years ago
I'm so proud of myself, I desoldered some 8 pin SOIC's with a $16 40 watt soldering iron! They didn't even melt(I lifted half the pad on a couple pins, though)! My iron has a nice tiny tip, and i keep it cleen. That helped a lot!
Sandisk1duo7 years ago
wow... i thought the brown capacitors were resistors, and the capacitors with stripes were diodes
1up7 years ago
Awesome! Great method for desoldering them! I may use this sometime.
Excellent! I bought a few SMD LED laden gift cards for a $1.50. I figured at a dozen leds per card it was worth seeing if I could harvest them off the pcbs. Now I know how! Gracias!
fingers7 years ago
I do thr same as a hobby and keep the bad stuff out of the landfills..It also makes good art stuff..
Sawbones7 years ago
check this link for storage

http://www.engineeringlab.com/supkiten.html

or you can do it on the cheap like me and get those small plastic coin holders for dimes....
This is a great technique. Complements the hot-air stripper gun method perfectly. (Like, when you really just want one piece out of a given area.) Thanks.
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