TaoGem Gemstones

A Glance at Jewelry – Scale Silversmithing Methods by William Fretz Designs 
I would like to acknowledge the Lapidary Journal / Jewelry Artist magazine. Permission to do this blog entry was kindly provided by William Fretz. The original article was from the November 2007 issue.Forging is a controlled method of moving metal by stretching or compressing it using a hammer and a stake. There are many forging methods used to shape sheet metal. Unlimited variables contribute to the ultimate form and finish of a forged piece. Wood, metal, and plastic tools – both stakes and hammers – and their many combinations and shapes can all contribute tot he final outcome of a forged piece. The key to all successful forging is a delicate balance between force and control, and like all techniques, good hammership comes with practice. There are three main hammering methods: Raising, embossing, and planishing – metal is manipulated in different ways when the three techniques are used.Raising compresses metal down to the stake without stretching it. The trick is to angle the metal off the stake so there is an air gap for the compression.

Embossing stretches metal by hammering from the inside. When the metal is hammered into a cavity, it’s called blocking – an alternate embossing method. Freeform embossing can also be done with a sandbag.

Planishing smooths the metal against a stake by overlapping the hammer blows. This stretching technique also forms the metal to the shape of the underlying stake. With practice, a morrorlike surface can be achieved.

For all forging, the size of the hammer as well as the corresponding stake will be dictated by the size of the work.

RAISING HAMMERS

(Photo 1) Wideraising hammers can be used to raise sheet metal into a bowl against a wooden or metal stake. They are also useful in cylinder forms for raising metal into a concave shape. Subtle planishing of concave shapes is possible with the narrow, curved faces of this type of hammer. Here the wide raising hammer is used to form a tube into a concave shape on a concave stake.

(Photo2) The tighter curves on the faces of a narrow raising hammer allow the raising of small sylinders and concave shapes. The thinner head allows this kind of hammer to fit into tighter curves for both raising and planishing. It’s also useful for fuorging and texturing. Here, the narrow raising hammer is used to raise in (thicken the metal in) the neck of a small sterling bottle.

A short narrow raising hammer can subsititure for the narrow raising hammer when a smaler striking head and a lighter tough is desired. Likewise, a short, wide raising hammer has a profile which makes it a more subtle substiture when a lighter hammer is desired.

EMBOSSING HAMMERS

(Photo 3) Small embossing hammers are used to form small raised areas by hammering from the inside in preparation for chasing or general shaping. A very fine dimpled texture with infinite variations can be produced depending on the strength of the blow. The small end of the embossing hammer can be used to texture surfacees, both flat and curved.

(Photo 4) Larger embossing hammers are used to dome metal from the inside. Metal is stretched from the inside as it is supported on a sandbag or a depression carved in wood. Doming a piece of metal before raising makes ite easier to control because the shape becomes rigid. This type of hammer also leaves a very interesting dimpled texture on flat or slightly domed metal if the mannering is done on the outside of a form while supported against a stake. The embossing can be used to stretch a small bottle from the inside.

A more rounded narrow raising or embossing hammer can emboss narrow raising or embossing hammer can emboss narrow pod or oblong shapes, like a spiculum form. Smoother overlapping marks are easier on long thin shapes tthan with a round embossing hammer.

Embossing hammers with wider, longer profiles are ideal for blocking bowls and broader width strips into concave shapes. As with all embossing hammers, this type of hammer is intended to stretch the metal from the inside.

PLANISHING HAMMERS

(Photo 5) The planishing hammer is for smoothing metal and is typically the most used hammer. The round head is used if the metal being worked has hammer markds from a previous round of raising that need to be smoothed out. The flat head of the hammer will also refine the markds made by the round head for a nearly smooth finish. This hammer is also used to size rings and form bezels. It’s a good general forming hammer when used with mandrels and stakes. Here, the round head is used to shape a hollow donut form from a flat tube.

(Photo 6) Smoothing and squaring the corners of a band ring can be accomplished with the flat side of the planishing hammer.

(Photo 7) Asingle ended planishing hammer with inserts has a plastic head that can be removed with a hex key. The flat plasic head forms metal while leaving it smooth. The metal head is slightly domedto make it easier to strike flat or slightly dome metal. I designed this hammer primarily for the bench jeweler who sizes rings and only wnats one hammer. Here, the plastic head will move the metal with out leaving marks.

Double insert hammers have interchangeable plastic heads of carious shapes that work the metal without leaving marks. The wide range of head shapes duplicate metal planishing, embossing, and raising hammers, and are useful for forming metal without stretching it. The hammer head is heavy enough to move metal with assurance.

TEXTURING HAMMERS

(Photo 8 ) Sharp texturing / raisig hammers are primarily for rings or other metal surfaces where very detailed hammered textures are needed. This type of hammer can also be used to make extremely tight curves when raising portions of jewelry. Here, the sharp edge of the hammer is used to form the texture on a band ring. A shorter, smaller version can be used on wire or other very small surcases. A texture that simulates raw silk is produced with a planishing hammer that has been randomly ground on the heads. It’s similar to a texture that could be rolled onto flat metal in a rolling mill. This type of hammering makes it possible to produce the texture on dimensional shapes.

MALLETS

Plastic head mallets are used to flaten and shape metal without leaving marks.

This entry was posted on Saturday, January 17th, 2009 at 8:20 pm and is filed under Lapidary Shop Tutorials. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.