Sal Ammoniac 1/2 lb.
Also Sal Ammoniac, tinning block quickly cleans any carbon build-up that collects on the tip of a soldering iron. Simply rub the tip of a hot iron against the block and in seconds, the tip is clean, bright and hot. The 1/2 lb. block lasts a long time.
Use tinning block occasionally to re-tin the surface of your soldering iron tip. A moist soldering iron sponge, is ideal for routine maintenance while soldering to keep the tip clean.