Grinding

Certain shellcraft applications require some grinding of the shell lip or hinge area. This is easily accomplished with a 10-inch bench grinder of the type commonly sold in hardware stores. For example, MMDC's bench grinder (Figure 10), manufactured by Delta Tool Corporation, was bought in Palau's local Ace Hardware store. Nearly any 8-inch or 10-inch bench grinder will do, however.

Sometimes T. derasa and T. gigas shells must be ground prior to use in making bowls or serving dishes. The grinding process removes nicks and irregularities in the lip of the shell and eliminates the sharpness of the lip, which in some circumstances could pose a risk to consumers.

Grinding the lip of a giant clam shells is a quick, easy process that, done properly, should not require more than one minute or so per shell. The shell lip is held lightly at a 90 degree angle to the face of the grinding wheel (Figure 11) and moved rapidly in a horizontal direction so that the entire length of the shell lip contacts the wheel. The object is not to remove large amounts of shell but simply to dull the edge of the lip and to smooth out irregularities. After grinding, rinse the shells in fresh water to remove dust before doing any further crafting.

H. hippopus shells used in making night lights also require some grinding. The H. hippopus shell base is held directly against the grinding wheel for perhaps 30 seconds or so, to flatten the base where it will be glued to the stand of the acrylic base night lights. The entire umbonal area of the H. hippopus shell is removed to allow mounting it shell directly on top of the bulb base fixture of the wall socket night lights.

Although a good bench grinder may cost $200 or more, it is a very sound investment that will quickly pay for itself in shellcraft sales. Keep in mind, too, that the bench grinder has many other uses and will be in constant demand among friends, neighbors and family for sharpening knives and machetes. This is a nice little community service that does not reduce the effectiveness of the grinder for shellcraft production.

Standard safety precautions in the use of bench grinders include: wearing eye protection, short sleeves, gloves and an industrial quality respirator designed specifically to remove dust particles. These masks and replacement filter cartridges are available at any good hardware store.

Eye protection is essential because sharp-edged shell chips are inevitably thrown off the grinding wheel in the direction of the user's body.

Long sleeves and other types of loose-fitting clothing must be avoided when using a bench grinder because the fabric may get caught in the wheel.

Gloves should also be considered a mandatory safety item for the operator of a bench grinder. A grinding wheel can destroy human flesh astonishingly fast when one accidentally jams one's finger or thumb into the moving wheel. This is excruciatingly painful, not to mention potentially disfiguring, as those of us who have experienced it know. Don't take chances! Wear a pair of sturdy work gloves when operating your grinding wheel.

A respirator is vital to prevent inhalation of the dust generated by grinding the shells edges (Figure 12).