Processing Printer/Scanner Light Strips

[Tom565]

Hi. I've collected a small pile of these lights from scanners. They all contain around 100 gold bonding wires that are visible to the eye. I'm just not sure how to remove the wires from the actual light. I figured soaking it in HCL would lift the base of the wires from the board but would it detach the wire from the glass too? Any other possible ways to process these?

I believe the glass strip is held down to the board by adhesive.

 

[niks neims]

Hi. I've collected a small pile of these lights from scanners. They all contain around 100 gold bonding wires that are visible to the eye. I'm just not sure how to remove the wires from the actual light. I figured soaking it in HCL would lift the base of the wires from the board but would it detach the wire from the glass too? Any other possible ways to process these?

I believe the glass strip is held down to the board by adhesive.

I've also wondered about these...
to me it seems that those wires are encapsulated in some kind of adhesive/gel, so my guess is incineration first would be needed to free them, have not done any such recovery on material like that myself, though

anyway, can anyone shed some light on this material:
are those wires similar to IC bonding wires?

 

[anachronism]

When you look at the cost of these complete items it's extremely low compared to the cost of gold bearing ICs. Logic suggests that these wires are most likely to be at best gold plated rather than solid gold.

This tends to be one of those cosmic constants. If something is cheap and mass produced then it's far less likely to contain decent PMs when compared with a board that costs hundreds or in many cases thousands of dollars.

Naturally there are exceptions to the rule, however those exceptions don't disprove the rule.

 

[kurtak]

When you look at the cost of these complete items it's extremely low compared to the cost of gold bearing ICs. Logic suggests that these wires are most likely to be at best gold plated rather than solid gold.

Jon

The bond wires are most definitely real (solid) gold wires (tested with nitric - no reaction)

I don't know about cost to manufacture a single IC chip compared to cost to manufacture one of these boards but it really doesn't matter because the cost to manufacture something & the cost of materials (in this case the gold) used in it's manufacture are two different things

Material cost can play a small part - or - a large part in the manufacture cost depending on things like engineering cost, labor cost, production volume, etc. etc. etc.

A single quad IC chip with 160 gold bond wires has "about" 0.0065 of a gram gold in it - at todays spot price that equals "about" 32 cents

That means that if there is "about" 100 bond wires on one of these boards (assuming the wires are "about" the same size) there would only be "about" 20 cents worth gold bond wires (maybe 35 cents IF the wires are longer &/or thicker)

My point being - at 20 - 35 cents in material cost plays a small part in the end product (manufacturing) cost/value

In other words - if they only made a few thousand of these boards they would have to charge LOTS of money (per board) to make a profit - even though there is only 20 - 35 cents gold in them

BUT - on the other hand - because they make these boards by the hundreds of millions they can sell them for a FEW dollar with the cost of the gold only being 20 - 35 cents of that few dollars per board

Kurt

 

[anachronism]

Fair play Kurt!

 

[Tom565]

Thanks for the reply's. I might try cutting them up in smaller chunks and incinerate them next time I do a batch of IC chips but keeping them separate. I might also just try soaking one in HCL for a while to see if it will left the bonding wires off the glass which it will most likely not. I'll let everyone know how I make out in the future.