Wash your Friuls in anything from soapy water to alcohol; just make sure they are completely dry before using Blacken-it. Any residual soapy bubbles will prevent the Blacken-it reaction at that point and leave it bare metal. Likewise, when soaking the tracks in Blacken-it, be sure to agitate the soaking container periodically, as air bubbles trapped in nooks and crannies will also prevent proper reaction. Keep an eye on the reaction's progress; for a while nothing seems to happen, and then reaction comes quickly. Results are haphazard with gray to dark gray, mottled gray, and sometimes a dark brownish

color will result. If you get a white powdery residue, no problem, it will easily brush off.