"GOLD" boards

Discussion in 'General Electronics Chat' started by Jshort, Aug 6, 2013.

  1. Jshort

    Thread Starter New Member

    Aug 6, 2013
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    found a bunch of boards with "Gold" pin etc. what do I need to do with these??
     
  2. mcgyvr

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    Oct 15, 2009
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    matching gold slippers of course..
     
  3. ian field

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    Oct 27, 2012
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    Some scrap merchants pay good money for gold plated boards, if there's a lot of gold plated chips; throw the whole board in the sack - if only the edge connectors are gold, shear them off with tinsnips and keep the rest of the board for component harvesting.

    Some cheapskate manufacturers used phosphor-bronze edge connectors, so keep quiet and hope the scrappie can't tell the difference.
     
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  4. Jshort

    Thread Starter New Member

    Aug 6, 2013
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    Now to find someone that will take these off my hands... thanks for the heads up.. Not sure where to start. I guess off to the yellow pages, unless you know someone ?
     
  5. ErnieM

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    Apr 24, 2011
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  6. #12

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    Nov 30, 2010
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    I have wondered how much effort is required to scavenge some 50 micron thick gold plating, as in, how could that possibly be profitable? I guess it is profitable, but not for half a dozen boards. Too much up-front investment to earn it back in a day. Sell them to somebody that is running a large batch.
     
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  7. Jshort

    Thread Starter New Member

    Aug 6, 2013
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    I just can't toss them for Tin weight, So I am hopeful that someone wants them..
     
  8. ian field

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    You can etch the copper tracks out from under the gold plating - but it takes weeks, even months and it'll cost more in ferric-chloride than the gold is worth.
     
  9. mcgyvr

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    Oct 15, 2009
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    depending on how many boards you have its not worth the time/gas,etc... just throw them in the trash (depending on what country you are in) and move on.

    Our "scrapper" wants at least a few 50 Gallon drums filled to the brim with PCB's before they even look at it.. We keep all our scrap and once or twice a year fill up a semi trailer with it. (our scrap consists of PCB's/copper wire/fabricated aluminum and steel/copper bus bars,etc..)
     
  10. ian field

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    A few decades ago I gave about 1/2 dozen boards that had all the copper area overplated with gold, to a local bloke who frequently weighs in scrap - about a week later he came up to me and handed me nearly 10GBP - in those days that would pay for a pretty good ****-up, 2 nights running.

    The cash might have been more, but I kept the board with the 8008 on it.

    Come to think of it, he was a bit of a dodgy character - so he probably took a hefty cut before passing it on!

    Just lately gold exchange shops have been springing up everywhere - they're reputed to be serious rip-off merchants with tales of only £25 for a £500 piece of jewelery - but gold prices must be at an all time high for them to be so eager to con people out of it.
     
  11. GopherT

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    Nov 23, 2012
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    Gold has a density of 19 grams/cc and, at a plating thickness of just 50 microns, a 10 cm x 10 cm plated will take 0.5cc of gold and weigh 9.5 grams. That is 1/3 ounce or $400 at todays rates.

    I am surprised so I would appreciate that someone checks my math.

    I have no idea how much it will cost to recover (remove) the gold from a PCB or separated it from the tin solder.
     
  12. THE_RB

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    Feb 11, 2008
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    Your math seems ok to me; 10cm x 10cm x 0.005cm = 0.5cc.

    So I think the gold plating must be MUCH thinner than 50 microns?

    A quick google found this;
    BACK - Multech PCB technologies Co., Ltd
    Immersion Gold / Silver / Tin Flash Gold. Hard Gold plating. Selective thick Gold
    Plating Gold Finger (Gold thickness up to 3um)
    Plating Silver (Silver through ...
    www.multech-pcb.com/ability.asp.htm - 35k - Cached


    Which seems to imply that a THICK gold plating on PCB is 3um, not 50um. Some more googling will probably show standard thicknesses, and as a guess I would think modern plating uses less gold than old fashioned '60's '70's plated PCBs.
     
  13. ian field

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    Oct 27, 2012
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    You can dissolve the gold off the copper tracks (if you can remove the solder resist without abrading away most of the gold!) with mercury - again, probably not economically viable, and mercury is very toxic - especially when you have to boil it off with a blowtorch!
     
  14. ErnieM

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    Apr 24, 2011
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    The answer is "substantially less then the reclaimed gold is worth."

    I have several stories on this. My favorite was a used equipment dealer who was called in as a last resort to purchase a mainframe computer. He walked around the unit (remember mainframes were the size of a large room those days), looked inside and saw all the boards were first rate electronics, every PCB, connector, and most of the parts were gold plated.

    "It's scrap at best" he offered, and gave then a quote of several thousand dollars to haul it away. An agreement was reached and they paid him to load up their scrap... and he then tripled his haul at the gold reclaimer.

    I spent much of my professional career in the hybrid industry where the standard package is gold plated, as are the pins. Rejected units all go into a scrap bin which is periodically sent off to a reclaimer. A decent sized operation will generate many 10's of thousands of dollars in gold scrap over a year.

    The reclaimers give you back gold bars. They are heavy and huge.
     
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