Since the 1980’s laser beams have provided an alternative to the cutting blades of the rotary engraving systems, making it possible to cut and engrave a variety of materials by burning into or through them. There is still much that rotary engravers can do that is difficult or impossible for lasers to achieve, but laser engraving and cutting has really come into its own since that time.
Need detail? The above pendant is little more than a half inch in diameter.
Because there are no cutting blades to sharpen, swap out and adjust for the varying tasks necessary to complete a rotary engraving job, lasers engraving has proven to be a much more efficient method for the most part. Its strength lies in its accuracy and precision when it comes to rendering detail or cutting intricate patterns. A laser beam is only a few thousandths of an inch in diameter and holds that diameter even when cutting through half inch acrylic. The thinnest rotary cutting tools are much larger than that and most rotary engraving blades are V shaped, removing a wider swath the deeper the blade cuts into the material.
This fighter jet was cut from .5″ acrylic and all of the exterior details were laser engraved onto the surface, down to the last rivet.
Laser cutting, like all rotary engraving and cutting follows a path created in the software. For instance, it can cut a 2 inch tall letter form with great accuracy out of a piece of thin wood or acrylic by following the outline of that letter.
However laser engraving differs quite a bit from rotary engraving. When a letterform is rendered using a rotary engraver, the cutter follows concentric paths to cut that image into the surface. The laser, when engraving, does not follow a path. Instead, it sweeps in a straight line across the material, firing when it encounters black in the design and not firing when it encounters white in the design and then, much like a farmer plowing a field, turns, moves down one row and sweeps back in the opposite direction and so on until everything that appeared black in the design has been burned into the surface of the material. And though a tedious process it does all this with lightening speed and accuracy. It can render tiny type in great detail and even the tiniest halftone dots in a black and white photo.
The photo in the above display piece designed by Jim Sadler was photo-laser engraved.
A laser can cut acrylic, thin wood, leather, paper, etc. and engrave those same materials along with metal, glass and stone. Since the same beam cuts and engraves, it can do both one right after the other without stopping the job to change or adjust tools, etc. There are industrial lasers capable of cutting metal and perhaps stone though such machines are generally beyond the scope of the awards and engraving industry.
As with the rotary engraver, new materials, products and improvements are constantly being developed for the laser.