1-way: For this purpose necessary a DC source 25-30V and the concentrated solution of table salt. Connect (+) pole of the source with a foil-clad paper-based laminate on which the future conductors are painted over by a nitropaint. To other clip "crocodile" connected to (-) pole of a source, attach the wadded tampon plentifully impregnated with the solution of table salt. Slightly having pressed a tampon to foil, move it on the foil. Thus the foil which has been not protected by nitropaint is as washed off. To avoid foil heating, impregnate a tampon with a solution is more often and move tampon smooth circular motions. It is recommended to begin with the opposite end from a connected place.
After pickling the nitropaint is washed off by acetone. Rough edges conductor paths are straightened with a scalpel.