Dealing with Scale

Oxidation occurs during the heating process, as air contacts the steel. This process creates what blacksmiths call scale or slag. In a properly built coal fire, positioning of the steel and control of the air blast helps to reduce the build up of scale on the work piece. Scale that is left on the steel during forging forces the scale into the steel, leaving a mark on the piece. The greater the scale build up, the less attractive the finished piece.

The Forgemaster TM forge eliminates the need for the blacksmith to constantly tend the fire as with coal. This allows for greater production time in a much cleaner environment. In the heating chamber of the Forgemaster TM forge, the air blast is in direct contact with the steel. The atmosphere that enables greater production and ease of work can also increase the amount of scale. A few simple steps will keep your work looking clean and crisp.

1) Only heat what you can easily work. Don’t overload the forge with work pieces. The heating ability of the Forgemaster TM is exceptional, and most experienced blacksmiths find that they can only keep up with a couple of pieces at a time. A piece of steel left in a gas forge heating chamber too long will develop a larger amount of scale.

2) Use the lowest temperature possible to reach forging heat and keep you busy is the ideal. Set your Forgemaster TM pressure regulator at as low a pressure as possible to keep up with the work you are doing. When working on small stock use low pressure (5 or so psi ). Larger stock may require up to 10-12 psi.

3) Work an edge first. Hammering on the flat face will result in hammering scale into the work. Light hammering on an edge will cause the scale to break lose and fall off of the work.

4) Brush the scale off. If hammering an edge is not possible, bending the steel will also loosen the scale. If neither of these techniques is practical for the piece, use a large bristle wire brush (Butcher Block brush) to remove scale prior to forging.