Cutting and filing of silver ornaments

File cutting is the most basic processing technology in the production of silver jewelry, which should be mastered and used repeatedly in all stages of silver jewelry production.

incision

Cutting machine, steel scissors and silver scissors can all be used as tools to cut silver pieces, but the silver pieces cut by these tools have burrs and are not accurate enough. Silver wire can be cut with nozzle scissors and oblique scissors, but after cutting silver wire with these two tools, there will be oblique sections, which need to be leveled with a file. If you use a tiger's head to cut the silver thread, the part left behind is relatively neat, and it is basically unnecessary to trim it with a file.

If you use a saw to cut silver pieces, wires and tubes, the effect will be much better. Saw is the most basic jewelry making tool, which has a wide range of uses and can be used for simple and complicated silver cutting work. The saw is composed of a saw bow and a saw blade, which needs to be clamped firmly with the saw bow so that the saw blade will not loosen when cutting. There are many models of saw blades, and the commonly used models are between 4/0 and 8/0, of which 4/0 is thicker and 8/0 is thinner. We must choose the thickness of the saw blade according to the thickness of the silver sheet. Generally speaking, the thickness of the silver blade should be equal to the distance between the three teeth of the saw blade. For example, a 4/0 ~ 8/0 saw blade is more suitable for cutting with a thickness less than 0.6 mm (22 Ga. ), 3/0.

Our saw blade is suitable for cutting with a thickness not exceeding1.3mm (16 ga. ), No.2/0 saw blade is suitable for cutting with a thickness not exceeding 1.6 mm (14 ga. ), and 1/0 ~ 4/0 saw blades are suitable for cutting with a thickness not exceeding 3 mm (9 ga. ). When cutting curves, it is best to use a thinner saw blade.

Saw can be used to cut decorative lines, and also can be used to hollow out decorations. Hollow decoration refers to directly hollowing out silver pieces for decorative patterns, without hollowing out from the edge. The basic process is: firstly, transfer the pattern to the silver piece, drill a hole near the edge line in the pattern, clamp one end of the saw blade with the chuck below the saw bow, and pass the other end of the saw blade through the drilled hole, and then clamp the saw blade with the chuck above the saw bow. The saw bow and saw blade should be perpendicular to the silver piece, and then start carving patterns. Carving should start near the center of the silver piece, and then the pattern near the edge, which helps our hands to hold the silver piece tightly. The hollowed-out space should not be too narrow, at least the file should be able to be inserted and trimmed.

The surface plug is an indispensable auxiliary tool when cutting metal plates with a saw. There should be a V-shaped notch in the plug. When sawing metal sheet, one hand holds the saw bow, and the other hand presses the metal sheet on the watch plug, and the traveling direction of the saw blade always faces the tip of the V-shaped notch.

File grinding

The filing process is suitable for plastic and finishing engineering. Small pits and burrs, enlarged holes and grooves can be removed by filing. Files are usually made of steel, and the purpose of cutting metal is achieved through the grooves on the surface of the file. There are different types of documents, among which No.00 is thicker and No.4 is thinner. The following are the categories of files:

Hand file: This file is the largest jewelry file and comes in different shapes and lengths. There are two lengths, one is 150mm(6 ") and the other is 200mm(8"), among which No.2 flat file and No.2 semi-circular file are used most. In addition, a thicker flat file is used to cut metal more efficiently. For convenience, you can install a wooden handle for the hand file. Generally speaking, wooden handles and hand files are sold separately. When installing the wooden handle on the hand file, first light the lower end of the hand file with a musket, then insert it into the pre-drilled hole of the wooden handle while it is hot, and knock the wooden handle tightly on the anvil to complete the installation work.

Oil file: The volume of oil file is much smaller than that of hand file, which is especially suitable for trimming works with smaller size and more complicated structure, such as hollowed-out decorative works. There are many kinds of oil files with different thicknesses. A set of 2 # thick oil stalls, including all 12 shapes, is definitely a necessary tool for jewelers.

Special-shaped file: The size of special-shaped file is smaller than that of oil file, and the file head has many shapes. Special-shaped files are more suitable for works with complex structures and strange shapes, especially for polishing those beating around the bush.

Square-handle file: Square-handle file is smaller and thinner than oil file, and it is mostly used to trim exquisite jewelry and inlaid gems.

It is very important to choose suitable files for dressing, such as circular files for dressing holes, semi-circular files for dressing inner rings and flat files for dressing outer rings. In addition, the coarse file has high efficiency in cutting metal, and the fine file is used to remove the file marks left by the coarse file. Of course, the file marks left by the fine file need to be removed with sandpaper.

Never trim the work with a file when it is suspended, as this will have a poor trimming effect. For example, to trim the long side of a piece of silver, it is necessary to clamp the silver with a fixture and press it on the watch plug, thus starting the filing process.

The strength of file grinding is generally achieved by pressing the finger on the file. When pushing the file forward, the finger pressed on the file must be hard; When moving the file backwards, the file should be lifted up to prevent metal from touching it. If the file moves backward and has to touch the metal, our fingers on the file should be relaxed, so we must be very clear about the specific contact part between the file and the metal.

Carefully check the parts that have been filed, especially if this is a weld that needs to be welded. If this part of the filing is not smooth, then your filing technology needs to be further improved.

When filing a surface, it should be noted that the path of the file should always be consistent with the surface, otherwise the surface will be filed into a plane. Sometimes, the saw blade can also be used for filing, for example, we can use the saw blade to polish the sharp corners in the hollow pattern.