Potassium iodide is another gold etchant. No idea if it attacks nickel also.
If I find a little time, I'll go through the treasure trove of tech
documents Inge dropped on us a few years ago. I know there's an article or
two in there about which etchants eat what.

If there is no "magic elixir" for this job, maybe electrolysis? You'd have
to tie all of the conductors together.

And finally, another alternative is to simply wash the board in SN100
solder, then wick it off. The tin in the solder will pull off all of the
gold. Then getting the tin off should be relatively easy with the proper
etchant. It is common to have tin strippers in pcb shops. 

Wayne

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Grossmann, Günter
Sent: Friday, February 06, 2015 3:27 AM
To: [log in to unmask]
Subject: [TN] Stripping of gold

Hi all

I need to strip gold from Ni on solder pads but Aqua Regina eats away the
nickel as well. Has anyone got the formula for a chemical solution?


Best regards


Günter


______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please contact helpdesk at x2960 or [log in to unmask]
______________________________________________________________________