Monuments, memorials and decorative objects produced in granite can have a beautiful appearance. Examples of this range from smaller desktop commemorative items, to large memorials such as the National Monument to the Forefathers in Plymouth, Massachusetts. A passage of text or design on a granite piece enhances its look and explains its purpose. Granite engraving machines come in a few different types.
Engraving Pen Machine
Handheld equipment for etching on smaller pieces of granite include engraving pen machines. These typically look similar to a large pen in style, and have a strong steel, diamond or tungsten carbide tip. They use a vibrating action to enable the tip to etch into the surface of a granite piece and can produce finely detailed lettering or patterns. The machines operate using either electrical or pneumatic power.
Rotary Engraving Machines
Rotary engraving machines can also produce finely detailed work, with the machine wielded manually using electrical or pneumatic power. They have small cutting wheels, which spin at high speeds to enable them to etch into the surface of granite. Interchangeable wheels have a variety of shapes and sizes to produce different finished styles, with diamond and tungsten carbide wheels commonly used.
Impact Engraving Machines
Impact engraving machines feature a small metal frame that sits directly on top of a granite piece. The frame holds an engraving tip on a movable arm, which can strike down into the granite at high speed as it moves around to etch a design. The engraving can be programmed into the machine, allowing the production of more elaborate and intricate designs at much faster speeds.
Sandblast Engraving Machines
This style of machine uses computer control to sandblast a design into the surface of granite. The engraving process starts with the production of a rubber stencil, with the design cut into it and the stencil laid on top of the granite. This leaves the design open, while the remainder of the surface remains protected by the stencil. When placed in the sandblasting machine, a computer controlled nozzle directs a high-pressure jet of air and sand at the design to cut it into the granite.
Laser Engraving Machines
Laser engraving machines are one of the more versatile styles of etching equipment for granite. They typically work best on darker materials, and they can produce extremely finely detailed work. The machine features a computer controlled laser, which etches a design by removing the darker polished surface to reveal the lighter material below. Laser engraving machines produce standard lettering and design work, and they can also create lifelike photo style designs.