Brush-on Presto gels from Birchwood Technologies impart color, durability to metal

Birchwood Technologies offers several brush-on gel formulations that impart a durable, darkened finish to metal without the need to dip the entire part in a liquid bath container. They are designed for sheet metal that needs partial finishing and touchups.

Presto Black® gel is suitable for most nonstainless iron and steel surfaces of any size. It can be applied at room temperature to parts positioned vertically or horizontally , without runs or drips, the company states. The Antique Brown® and Antique Black® gels are designed for use on brass, bronze, and copper substrates to produce durable brown/black finishes.

The gel chemical reaction takes 2 to 10 min. following surface cleaning to remove oil, oxides, and welding flux. The user inspects for the right color tone and depth and finishes by rinsing the gel off with a wet sponge and sealing the finished surface.