Craftsman of the Month
As a rookie lapidary, I bought an "All-U-Need" flat lapping machine and plenty of slabs. I soon grew tried of making cabs, and had to think of something that I could make using my brand-new cabbing machine. A box made of stone, about the size of a cigar box, that my mother had in our living room impressed me. Since I have a 6-inch lap, I needed to make a box a lot smaller.
I soon came up with a perfect design that would maximize the space on my lapping machine. Its dimensions were about 2.5 inches by 1.5 inches by 1.25 inches. I figured out most of the problems with my design as they arose. It took me about two boxes to develop a "tried-and-true" method. Each box takes me about 12 to 20 hours to make.
The following are the basic steps:
Pick a shape of box that can be made with your machine (rectangle, square, triangle, hexagon). In this example, I chose a rectangle.
Make a template for the design using mat board.
Trace the design onto the slab(s): four sides, a bottom and a lid. I usually need at least 15 square inches of material.
Cut the pieces using a trim saw.
Grind the base of the box to the desired shape, and make sure the sides are perfectly parallel to each other and that the sides and the edge of the slab form right angles to each other.
Flat polish one surface of each piece of the box except the lid. The polished surfaces will form the inside of the box.
Take each of the sides of the box and grind the height's edge until it is perpendicular to the flat face. You should now have five pieces (for a rectangle) that are polished on one side and ground so that they have right-angled edges.
Glue the flat surface of one side to the edge of the base so that the right-angle edge of the side piece is even with the base and the other end sticks out.
Glue the other side pieces to the end that overlaps the base. Do this until the final side is glued on to complete the box shape.
Grind the top of the box until the side pieces are flat and the proper height from the base.
Place the lid piece on top.
Tape the box lengthwise, and grind the sides so that the lid matches with the bottom.
Remove the tape.
Tape the box around the middle, and grind the ends so that the lid matches with the bottom.
Remove the tape. The lid should now match the bottom perfectly.
Grind the bottom into the desired "shape" (round the edges and corners or give an edge or facet to edges and corners, etc.).
Dop the lid and grind it into a "cab" shape, retaining its dimensions.
Polish the lid and bottom using diamond laps to 14,000 to 50,000 grit.
Flat polish the inside of the lid.
Cut, grind and glue strips of material to the underside of the lid. These strips hold the lid on the box.
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