Trial fit the joint and make any adjustment to make the surfaces set flush. Use long straight strokes to keep the surfaces flat. The final shape can be formed very quickly with the use of a flat hand file. To form the male end of the joint, I use a pair of diagonal cutters ( a heavy pair of wire cutters) to form the basic shape. This will form the female side of the joint. Use a #1 saw blade to make the cut, and the fitting will be much easier. Put the ring back on the bench pin and from the outside saw inward to the previous cut at a 45° angle, opposite the first cut, to form a “V”. Loosen the blade and remove the ring from the saw. Be sure to keep the saw perpendicular to the shank. Slowly saw halfway through the shank (from the inside outward) at a 45° angle. Lay the ring flat on the bench pin and loosen one end of the saw blade and pass it through the ring. Personally, I prefer to form the joint by sawing. This angle can be cut in one of two ways, sawed or filed. The “V” should be fairly open, no sharper than 90° and open no more than 120°. One of the more common problems that jewelers have in fitting the dovetail is caused by trying to make the angles too sharp (acute). Because most jewelers are familiar with fitting a butt joint, I will focus on fitting the dovetail. The main reason for its infrequent use is due to two factors the jeweler is not familiar with this technique or the joint is difficult to fit properly. Although the butt joint is more commonly used of the two, the dove-tail is a much stronger joint. The dovetail joint is formed by making a “V” shaped cut or notch in the shank (when viewed from the side) and shaping the other side of the joint into a blunt point to match the “V” (Fig. The butt joint is formed when the shank is cut flat on the ends, and brought together to form a tight seam or joint. There are two common joints used butt and dovetail. If the ring is cut to be sized it must be rejoined. If the size of the ring must be reduced by more than two sizes, this technique is not recommended. After swaging, the ring should be stress relieved and polished. This step will eliminate the cupping that is produced on the inside of the shank from the rolled edges. Now position the ring on the ring stretcher or steel ring mandrel and bring it back to the desired size. Because this process tends to roll the edges of the ring inward, it is necessary to reduce the ring size one half size smaller than the intended size. Raise the ram and turn the ring over and repeat this process. Using firm pressure, push the handle of the ram down about half of the stroke. Slowly lower the ram and allow it to level the ring in the die. It is not necessary to lubricate the ring or die when it is being swaged.Ĭenter the ring in the die and position it under the ram. If the press has an adjustable ram, set it so the ram does not touch the surface of the die plate when it is at the bottom of the stroke. The surface of the die should be polished and free of any defects or rust. Select a die that allows about one third of the band width to protrude above the die surface. Flat bands and bands with patterns will be distorted by this process.īegin by annealing the band. This will affect the ability of the metal to upset (swage) uniformly. It is important that the band has not been cut and sized before. Swaging should only be used on plain half round wedding bands that are not tapered. Most commercial ring stretchers have a swaging set at their base. Swaging requires the use of a set of dies and press to force the ring into the die. There are two techniques that can be used to reduce the size of a ring: swaging or removing a piece of the shank. There are a variety of techniques used to affect the size of a ring. 2.61mm added to or removed from the shank will change the ring by one full size (US sizes). It involves either adding or removing a piece of metal from the shank of a ring to increase or decrease the diameter, or ring size. Ring sizing is a fairly straight-forward process, and one of the most commonly used by the bench jeweler.
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