Get the gold out of there

[labo_dan]

Hello,

Let`s get to the point... as you can see in the pictures... I want to get rid of that layer, it`s kinda trap for me to get inside to the gold. So... can you explain - teach me (and to other beginners) how to reach there inside and take the gold beneath of that layer. I`ve only refine gold in the past from fingers and pins... now I`m stucked in here. Please, please give us a helping hand.

Thank you,
Dan.

 

[etack]

unknown layer is solder mask search for it under lasersteve



Eric

 

[Geo]

memory sticks are not gold plated under the green.

touch pads could be gold under the green.

gold colored mylar ribbon is more than likely aluminum.

there are exception, but for the most part, thats what you will find when you learn what to look for.

 

[Smack]

Dan, in the second picture I can tell just from the internet picture that it's copper. Keep looking at the stuff you'll learn. A tip though, if the solder mask scratches off real easy AND it looks like gold then it probably is. But it's thin.

 

[egus]

http://www.goldrecovery.us/goldrecovery/videos/ShowVideo.aspx?id=soldermask&yt=0
lazersteve rocks!

 

[joem]

If you do not have one get a strong magnifying glass because what looks golden to the naked eye looks reddish (copper) under that glass.

 

[Sodbuster]

gold colored mylar ribbon is more than likely aluminum

Not when solder is involved. Look at the solder connection in the top left corner. You won't see aluminum take solder like that.

Ray

 

[Marcel]

That gold underneath the solderresist mask is usually flashgold if it was newer electronics (not older than 10-15years). Dont expect big yields. The hot NaOH removal method is more trouble than the result is worth it.
Dont get mislead if the vias( interlayer connectors that look like holes in the PCB) are golden. There is a special mask in teh process, for them that will only gold plated these areas.
I have only once encountered thick gold layers beneath the solder resist. That were PCBs from 1980s HP measuring equipment.
So unless it is not high end electronics from aviation, military or else dont expect teh gold to come off as foils - it will just swim away as if it was nothing. You will use more value in chemicals than the return is worth.

Edit: Since I like it quick and dirty sometimes: Use a heatgun and burn the layer away at 450°C. Scrub the PCB with a brush then. Outdoors and stay away from the fumes.