July '20

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G R A P H I C S - P R O. C O M 2 0 2 0 J U L Y G R A P H I C S P R O 4 3 For the horizontal alignment, I worked with the urn builder to make a wood jig that is perfectly squared to sit against my top ruler that I could place the urn against. I also checked the squareness of the ruler, which is adjustable, and made it perfect. I can now place each urn reliably in my laser in an efficient timeframe with great results. The next challenge was finding the absolute center of the urn to place my red dot tool on and tell my laser that is the starting point. I have a centering ruler I created that quickly locates the center of a product both vertically and horizontally. I also created a template from a piece of cardboard by cutting it out with the laser the cor- rect size and laser cutting a small hole in the perfect center. I now have two tools to orient my laser to the center of the product. I get great results and can complete each order (10 to 20 per order) in a reasonable time. SMALL CUTOUT PIECES Occasionally, I accept projects that include small cutout letters or graphics. I also sell a line of mini signs for Christmas villages and miniature railroad tables. I found that letters or pieces of a graphic were much smaller than expected or smaller than they looked on my computer screen. I quickly realized I needed to take into consider- ation something called the laser's kerf. What is the kerf? Even though the laser's beam, which performs the cutting of the material, is very small, it can be considered larger than expected when cutting small objects. My laser's beam is 0.003 to 0.0065 inches in diameter with a 1 1/2-inch lens. The hairline I draw with in my graphic software is the center point of the cut line, so the laser's beam will cut half its width inside the cut line and half outside the line. So, I will lose at least 0.0015 of my object being cut. That may not sound like a lot, but when you do the math, it might represent 10 or 20% of the object. It actually might be closer to 0.002 or more based on how slow (dwell time) the laser speed is set to. The slower the speed, the longer the beam sits over one spot burning away the material. If pieces to a graphic are too small or the insides of letters are cut too large, consider these solutions. Make the graphic or letter slightly larger than you need. You may need to experiment with one letter, perhaps the worst one. You might want to begin the enlargement with half of your kerf amount. Your kerf can be obtained from your laser manual or if you cannot easily find it, call your manufacturer's support team. Scale the letter up each enlargement by 0.002 until you find a satisfactory cut letter or graphic. Another solution to try is to increase your speed by 25% and laser cut multiple times. You can go up in speed in increments of 5 to 10% to see if that provides a cleaner cut. If the primary issue is the inside of letters, you can decrease the size of the inside cutouts by turning the letters to curves (Corel) or lines (Adobe). For instance, if the letter is an O, this can be accomplished in Corel by selecting the text, pressing Ctrl + K to break the text apart, selecting the letter, then pressing Ctrl + Q to turn the letter into an object. You will then have two black objects. Select the center of the O (alt select) and select white from your color palette. Bring the object to the top, Ctrl + Home. Shrink the center by 5 to 10% or a percent that will work. Different solutions provide the best results for different situa- tions. Document what has worked best for you as you may have the challenge in the future long after your memory of how you solved it. Meeting challenges can be fun, especially when you are not in a hurry. GP BOB HAGEL and his wife Dana own Eagle's Mark Awards & Signs, offering a full line of personalized products using laser engraving, sand etching, and full-color UV direct print on products. They have offered awards, recognition, and signage products to organiza- tions for more than a decade in the Southern California wine country. He can be reached at

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