With steel, corrosion to the surface will always be a problem, especially if the product / component is in contact with moisture, as carried in the atmosphere. One of the most cost effective ways of preventing tarnishing / corrosion to the surface of steel, is to ‘Oil Black’. This can be achieved on a small scale in schools, although strict safety precautions must be taken.
1. Clean and degrease the steel. 2. Heat to ‘red’ heat on a brazing hearth. 3. Use tongs to drop the steel into a container of old engine oil. 4. Allow to cool and remove the steel (now with a blacked finish).
BLACKING OF STEEL WITH A
CHEMICAL BLACKING SOLUTION
This is a process called ‘Cold Chemical Blacking and does not require the steel to be heated on a brazing hearth.
1. Clean and degrease the surface of the steel being ‘blacked’. 2. Use tongs to drop the steel into a solution of ‘Chemical Blacking’. Leave for no more than five minutes. 3. Remove from the blacking solution, wash with water, dry and drop in a ‘Dewatering’ solution. Leave for ten minutes. 4. Remove and wash in clean water, revealing a ‘blacked’ finish.
