We’d thought we’d look at some of the essential techniques, tools & processes used when filing precious metals – gold, silver & platinum.
Filing is an essential technique in jewellery making, and although simple in concept following proven practices combined with the right equipment and tools, ensures the job becomes a breeze.
Filing precious metals
Filing is used in jewellery making to remove excess metal, even out surfaces, smooth or to shape, form and texture pieces.
The actual files come in a variety of shapes, grades/cuts and sizes. The shape of the file you choose will depend on the job you are completing i.e. flat files are used for straight edges or convex curves e.g. the outer edge of a disc, and curved files are used on concave curves – e.g. inside of rings.
The cut describes the arrangement of teeth and therefore the amount of material the file will remove and the surface finish it will leave. The most often used, and useful file is a medium cut 2 file, (cut 0 = course, Cut 4 = fine) this general purpose file removes material quickly, and leaves only light markings which can be easily removed.
Common types of file types
In terms of types of file, both needle and hand files are the most commonly used in jewellers workshops. The common shapes of file are Flat files – a general use file for use on flat surfaces and outside curves, Square files for use in grooves or inside angles, Three square files for tight angles and difficult to reach areas, Round files for inside curves, Half round files for inside curves, Knife files for limited access corners, Crossing files for inside curves, Safety back files ideal for tight angles as serrated edge are only on one side.
Hand files - Range of over 150 available
Fitting a file handle
Needle files have an integral handle; however hand files often require a handle to be fitted. To fit your handle place the file in a vise with the ‘tang’ (where the handle is fitted) pointed upwards, then heat the tang until red hot ensuring you direct the flame upwards. Push the file handle onto the hot tang allowing the it burn into the handle. Then tap the handle with a mallet until the handle is secure.
Filing techniques for a straight line
When filing ensure that the metal is secured, as an unstable bench peg/metal will lead to inaccuracies and mistakes. When filing a straight line use long strokes, applying pressure on the forward stroke. Make sure that the file is level and that you watch the metal to ensure accuracy plus allowing the jeweller to continually assess the pressure/placement of your next stroke. When filing you should work at a steady pace, as an aggressive technique increases the chance of inaccuracy. Many jewellers mark there metal as a guideline to measure progress and to see where they need to file.
Filing techniques for curves (convex)
With a flat faced file place the file on the metal and push forward using a sweeping action that follows the curve, ensuring the file is level. Use marks to guide the filing process, and check the surface whilst filing.
Files – an essential jewellery tool
Skilled filing is a key technique that once mastered gives the jeweller great control over shaping metal and forming designs. However initially it takes practice, concentration plus a level of intuition to ensure accurate lines or curves are achieved. A complete jewellery tool kit will include a full selection of files – both needle and hand, of all shapes and sizes and cuts, and become some of the most used tools at the bench.