PCB boards, gold traces in middle layers

[olson13]

Hello, I am new to this quest of stripping and refining gold from PCB boards. I have some PCB boards that my work gave me that have gold traces that run through the whole depth of the boards. My question is, what is the best way to get that gold out of the layers? I was thinking about shredding them to a funeral dust, but am unsure if that would work. Any help anyone can give me will be greatly appreciated!
Thank you
Swen

 

[Yggdrasil]

Hello, I am new to this quest of stripping and refining gold from PCB boards. I have some PCB boards that my work gave me that have gold traces that run through the whole depth of the boards. My question is, what is the best way to get that gold out of the layers? I was thinking about shredding them to a funeral dust, but am unsure if that would work. Any help anyone can give me will be greatly appreciated!
Thank you
Swen

Welcome to us.
I have never heard about such boards, where do they come from?

 

[FrugalRefiner]

For gold plated boards, most folks use a copper chloride leach, also known as AP (for Acid Peroxide). Although older posts here suggest using a lot of hydrogen peroxide, we now all agree that only a small amount is needed to start the action.

It will dissolve the copper traces that are underneath the gold plating, releasing the gold plated layer as thin "foils".

You can find a lot of information on the forum about this process.

Dave

 

[Shark]

A very aggressive air bubbler in AP, and given a lot of time, will eventually get under the solder mask where the gold layer is. Scratch through the covering along the gold trace and run them in AP for smaller numbers of boards. The air bubbling hard will break up the gold foils into tiny pieces, but it also aids in releasing those pieces trapped behind the mask covering.

 

[Yggdrasil]

It seem to have slipped by, but he said the Gold layers was through and inside the board, hence my question of what kind of boards.
I have never heard about such boards.
Maybe they are just plated on both sides?

 

[haveagojoe]

what is the best way to get that gold out of the layers?

I think we could do with a little clarity here...
Do you mean these are multilayered boards, where the traces are sandwiched between layers of board, as well as on the surface? If so, it's very unlikely that the internal layer is gold plated.
If you mean traces on the surface, usually only the exposed parts will be gold plated. Sometimes high-end boards will have gold below the solder mask (which is kinda like a layer of paint, usually green), in which case it can be removed with a soak in lye if you really want to, otherwise as Shark says, just normal Copper Chloride etching will get to it eventually.