As with pliers and hammers, there are an astonishing variety of files on the market. They come in different shapes, sizes and cuts. Choosing the right one for the task is essential to ensure you achieve a good quality finish.
Files are used for removing excess material from a piece, such as after sawing to neaten the finished edge and to create a graduated finish to an edge. We always recommend to beginners that when sawing, work on the outside of the line and use a file to work the edge the line afterwards if necessary.
The cut of the file describes the arrangement of the teeth and therefore the amount of material that the file will remove. Cuts range from 0 which is the coarsest and will therefore remove the most material to 6 which is the finest which will remove the least material and will also leave the least marks as a result. The most frequently used file is a medium cut one, such as 2 as this will remove excess material quickly and leave only light marking which can easily be removed by emerying.
The shape of the file that you choose will depend upon the shape of the piece you are working on. If you are working on a flat edge, you will need to use a flat file. Also a convex curved edge, such as the outer edge of a disc, requires a flat file. A curved file is needed for a concave edge, such as the inside of a ring.
Needle and hand files are the ones most commonly used in making jewellery. Needle files have an integral handle and are smaller than hand files.
Files generally have teeth on both sides however, safety backed files are available with teeth in only 1 side so that tight spaces can be filed without causing damage.
The most common shapes are ‘flat’ for general use on flat and convex curves, ‘square’ for use in groves and right angles, ‘three square files’ for tight angles and spaces and ‘round’ and ‘D Shape’ for use inside curves.
As the teeth of a file only cut in one direction, avoid sawing backwards and forwards across the edge of your piece, you’re wasting your energy, blunting your file and potentially damaging your piece. Work with the direction of the teeth by filing away from you.
Never file on the same spot, work across the full length of the edge using long strokes and applying firm pressure to ensure a neat, even finish. When filing a convex curve use a flat file in a sweeping motion across the curve.
Ensure that your piece is secured in a non marking vice as an unstable working surface can lead to mistakes and inaccuracies.
Mark the point that you are working to and frequently assess the piece to ensure that you don’t file too far.
Filing is a skill that will take time to master; however with practice you are developing a precision technique that will give you great control over shaping metal.