Because the file is such a simple looking tool, most people are fooled into thinking that there is no right way to use it. However, this is not true. Proper filing is essential in jewelry work. An efficient stroke of the file is a very important operation that is often neglected by beginners. Filing incorrectly wastes time and causes unnecessary work. Careless filing waste precious metals, the jeweler should always strive to conserve the maximum amount of metal. Proper filing to a large extent, determines whether the finished jewelry will look professional or amateurish.
In all filing, keep the hand and forearm in one straight line. From this position roll the wrist from side to side for rounded surfaces. Do Not bend the hand down at an angle to the forearm. Putting pressure on the wrist in this bent position over time will develop corporal tunnel syndrome. Whenever exerting forward pressure on the hand, keep the wrist straight as possible.
All files are designed to cut on the forward or push stroke. The backward or pull stroke does no cutting, it only returns the file to the start position, ready for the next cutting stroke. An efficient file stroke is smooth, steady, and even, using the full length of the file. Use just enough pressure to keep the file cutting during the entire stroke. Many jewelers develop the habit of lifting the file from the metal surface for the return stroke. Others leave the file in contact, but allow it to lightly slide back to the tip. Pressure is then again applied on the cutting stroke. As with all techniques, each jeweler gradually develops an individual way of filing. Regardless of how one eventually develops the filing stroke, the important thing to realize is that the tool is designed to cut only on the forward movement.
When working in areas of critical fit or precise edges, it is wise to lift the file on the back stroke and take careful, deliberate cutting strokes. This technique permits constant visual evaluation as the desired surface or shape develops.
Hold the work steady and move only the file, paying attention to the angle of which you are holding the file. Work with steady, even, long strokes. Frantic aggressive filing or short, broken, "fiddley” strokes will produce in-accurate results.
Brad