Harvesting electronic components

Discussion in 'General Electronics Chat' started by Gdrumm, Feb 19, 2010.

  1. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
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    I have been scavaging old electronic devices, and harvesting the components from them, but I'm wondering what's the best way to do this.

    (I do ventilate the garage while doing this)

    I've used a soldering iron, and a handheld solder suction device
    I've used a Radio Shack Solding iron with suction bulb
    I've flamed the back of a board (sometimes starting the board on fire)
    I've laid out boards on an old kitchen griddle, and allowed it to get hot enough to pull components out

    Is there a better way?
    Does overheating weaken or destroy various components?

    I'm going after resistors, capacitors, diodes, transistors, relays, transformers, rectifiers, switches, etc.

    Thanks,
    Gary
     
  2. retched

    AAC Fanatic!

    Dec 5, 2009
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    Heat gun. Under $20us from Harbor Freight. Heat the solder side of the board on low setting. Use a pair of pliers (I protected the jaws of mine with Plastic Dip) To pull the parts. Takes a few seconds.

    Give this thread a look:
    http://forum.allaboutcircuits.com/showthread.php?t=34359

    We just talked a lot about various methods of (de)soldering.
     
  3. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
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    Good tip, and good links.

    I'll buy a heat gun and give it a try.

    Thanks,
    Gary
     
  4. Externet

    AAC Fanatic!

    Nov 29, 2005
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    Or save the boards populated, to extract the parts when needed. Depending on the project, many times sawing-off a section of the board contains the wanted circuit, etched pcb included.
     
  5. eblc1388

    Senior Member

    Nov 28, 2008
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    Other methods:

    1. Open charcoal stove
    [​IMG]

    2. DIY solder POT

    [​IMG]
     
  6. retched

    AAC Fanatic!

    Dec 5, 2009
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    Woah, I guess if your in a Mad Max type situation and you need to whip up a detonator from an old radio and a modem, you could use these methods. :)
     
  7. BMorse

    Senior Member

    Sep 26, 2009
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    I think I will stick with the Heatgun method!:eek:
     
  8. retched

    AAC Fanatic!

    Dec 5, 2009
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    I have a little database I use. I keep the populated boards in a box, labeled. The main ICs are inputed into the DB. So when I need a part, I do a search. It will say, for instance, NE556 on board(s) 7a, 19g, 19j

    That way I can pull the board and pull the component when needed. I actually makes storage easier.

    Update the database to remove the chip from the database when its removed from the board.

    Masking tape and a sharpie keeps the boards labeled.
     
  9. eblc1388

    Senior Member

    Nov 28, 2008
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    Must clarify the above images has been taken from the internet. Most probably practiced by people salvaging components in villages in Asian countries.
     
  10. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    Electric skillets/hot plates work too. Some people also use them to solder new boards(SMT).
     
  11. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
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    I bought the heat gun at Harbor Freight, on sale for $9.00 + change, works great.
    About 8 - 10 seconds on high to loosen the solder enough to pull the parts out.

    Watch out for plastic on the component side however, I fried a buzzer (I also melted some bothersome glue).

    Great tips,
    Thanks,
    Gary
     
  12. retched

    AAC Fanatic!

    Dec 5, 2009
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    Use the lower setting. It may take a second or two longer, but thats at a far lower temp. You are using 1100 deg F. it only takes about 450 deg F to melt the solder. You will do less damage.
     
  13. jgessling

    Active Member

    Jul 31, 2009
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    Thanks for the tip. Last night I melted a 7 segment LED display I was trying to get. I gave up for the day, then later read your post. It seems my heat gun, which I originally bought to remove paint has 600F and 1100F settings. This morning I used the lower setting and grabbed the other display no problem. New better attitude didn't hurt either. Thanks again.
     
  14. retched

    AAC Fanatic!

    Dec 5, 2009
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    Any time. This thread should help others from doing the same.
     
  15. timd

    New Member

    Jul 15, 2010
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    I have found the best luck in harvesting old tv's found on the side of the road ready for the trashman. Not only do you get many cap's, resistors and diodes (I found the res. and diodes are hard to pull unless you chisel the leads), but you get all the wire and sometimes great pots.
    I personally have used the 22.00 heat gun at walmart for pulling.

    The best old tv's also have the coolest knobs you could find for transplanting to guitar pedals. Also, many defunct curbside stereo silverface (if you know what I mean you get it) recievers and tape decks have the coolest knobs you could get! Let me know if you agree!!

    ****I do have a question without a picture to back it up - what are those metal things that rise about 2 inches above the PCB on old TV's? They are rectangle in shape and have a colored circle at the top. Anyone? I have a ton of those, and I need to know if I should keep them or not. I specialize in guitar pedals, but have never seen them in a breadboard.
     
  16. tom66

    Senior Member

    May 9, 2009
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    Can you post a picture? You might be talking about the flyback transformer.
     
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