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Room Temperature Blackening Solution
For Powdered Metal, Iron And Steel
Black-Magic™ RT S30 liquid concentrate is diluted with water and used at room temperature for blackening iron and steel by immersion. Black-Magic™ RT S30 is recommended for blackening powdered metal ,cast and malleable irons and forged steels. It is designed for low smut rather than jet black.
Acid-resistant tanks, tumbling barrels, baskets, hooks and racks must be used with the RT S30 and Black-Magic™ Predip P solutions. PVC, plastic lined or rubber lined tanks and plastic coated hooks and racks are suitable. Mild steel may be used for the cleaning, rinsing and sealant tanks.
Items to be blackened must be thoroughly cleaned and deoxidized. Some experimentation should be done with sample parts to determine the degree of cleaning and activation required to produce a uniform black finish. Parts to be blackened should be protected from rust during fabrication and in-plant storage prior to blackening to minimize surface preparation.
The type and degree of surface soil will determine the length of time required for cleaning and the number or cleaning steps and cleaning temperature. Lightly soiled parts can be cleaned in two to five minutes at room temperature with an 8 oz./gallon solution of Mi-Clean™ 100. Heavily soiled parts may require a longer immersion time and temperatures upwards of 180° F.
Surface rust, if present, should be removed with 5 to 20% solution of Acid Brite 40 for cast iron at room temperature. Immersion times will normally range from one to five minutes. Muriatic acid should not be used to remove rust from cast iron. Use Acid Brite 40 only.