Homebrew PCBs

hello i need to take off solder mask to see the connection about processor amd ... 
please someone know how to take off that green coat ?
thank you very much

Good luck with out industrial chemicals

-----Original Message-----
Date: Wednesday, October 28, 2009 10:20 am
To: Homebrew_PCBs@yahoogroups.com
Subject: [Homebrew_PCBs] take off soldermask green
From: "ralph" <goodsurfer2000@...>

hello i need to take off solder mask to see the connection about processor amd ... 
please someone know how to take off that green coat ?
thank you very much

Red fuming nitric acid should dissolve it, as it is a resin, but it will 
also dissolve the copper and the fibreglass resin, if you aren't careful.

Leon
--
Leon Heller
Amateur radio call-sign  G1HSM

leon Heller wrote:
>   
> Red fuming nitric acid should dissolve it, as it is a resin, but it
> will 
> also dissolve the copper and the fibreglass resin, if you aren't
> careful.

All the care in red fuming nitric acid will destroy any solder, pads,
pins and tracks under soldermask.

Normal people simple scratch it with a not sharp tool when repairing a
damaged track. But the exposed problem is understandable.

If one wants a chemistry, hot desmear (or etchback) solutions used in
PTH (or multilayer) production before plating activation seems to fit.
Like permanganate, or better, ethanolamine based solutions. But there
are also epoxy glue cleaners on the marked.