November '20

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A W A R D S & C U S T O M I Z AT I O N 8 8 G R A P H I C S P R O N O V E M B E R 2 0 2 0 G R A P H I C S - P R O. C O M Y O U R L A S E R A T W O R K olution, especially if it's a rush job and it might be an acceptable solution. You may also slow down your speed or increase the power some, but there are no guarantees. MATERIAL AND CONTRAST The material you engrave on makes a dif- ference as well. Thin, coated metal may engrave out well while a textured, layered acrylic will not. The thicker the surface you must laser through, the greater the chance the line or text won't be com- pletely lasered out. Material color matters as well. The higher the contrast of the color of the en- graving area versus the background color, the better small objects and thin lines will stand out. There are treated metal substrates that laser to black or another color. If your black looks gray instead of deep black, you will lose thin lines and small objects. You have to have your laser settings just right to get deep black and high contrast. I found copper and gold provide less contrast with black text than a silver metal. If you have the thin/small challenge, keep material choice in mind while help- ing your customer choose a product. Glass and clear acrylic are likely the least contrasting material, especially glass that has been laser engraved rather than sand- carved. Laser engraving provides a mark by leaving tiny cracks in the glass. These tiny cracks offer a less sharp image than sandcarving. Cast acrylic turns white when lasered against a clear background. With acrylic products, try not to laser deep; just turn the surface white. Lasering grayscale im- ages with thin lines will be more chal- lenging. When the substrate is wood, you usually engrave deeper but have much less con- trol of the color of the engraved area. Thin lines and small objects are not likely to be engraved deep. Laser settings are especially important to make sure the burn mark penetrates the wood but is not overly deep. Color-fill may be necessary to have the engraving stand out whether you have small objects or thin lines or not. Wood burns differently, not only because of the species, but how many oils are left in the wood—wood dries out over time. CUT LINES Lasers cut as well as raster or engrave. How does your laser know what to cut? It is typically the thickness of a line. In CorelDRAW, the term "hairline" is used for lines that have a thickness of less than 0.01 inch. My laser cuts the line unless I This graphic had a black background. I used Corel- DRAW to invert the color, changed it to grayscale, vectorized it, and turned it into a black-and-white graphic. Look at the last graphic on the right. The line widths will laser well. However, if you look close- ly, there is a large number of small objects that may be just lasered enough that it makes the graphic look dirty. I would remove all the small objects to get a sharp, clean look. Effects > Transform > Invert colors Vectorized Black & White Inverted Grayscale

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