Identify the primary types of sharpening systems and learn about the features and functions available on these devices.
Angle adjustment is another consideration. If all you'll ever need is a square edge, then you can probably live without it. Even though a square edge is suitable—if not preferable—for many screen-printing jobs, the need may arise for a different profile. As noted earlier, diamond wheels can shape various blade profiles as they grind. But some sharpeners come standard with angle adjustment. This function allows the operator to adjust the squeegee's position in such a way that the sharpener can produce single and double bevels at virtually any angle.
How little material can the machine remove, and how accurately can the unit remove it? These questions are addressed by a system's minimum cutting depth and blade-height tolerance. Wheel and belt sharpeners offer minimum cutting depths measured in thousandths and hundredths of an inch, respectively. Knife units support minimum cutting depths measured in hundredths or thousandths of an inch. Blade-height tolerance refers to variations that may occur from end to end on the squeegee blade. Squeegee sharpeners listed in the product-comparison chart range from ±0.0004 to ±0.006 in.
Other specs to keep in mind are maximum squeegee length and cutting speed, both of which should be selected to match the applications you normally handle. If possible, leave some room for growth. Machines on the market can accommodate squeegee sizes for use in printing garments, graphics, industrial jobs, and more. You can even tackle 181 in. of squeegee blade at once with one of the models listed in the product-comparison chart. And manufacturers will generally build the machines to custom lengths as well.
Screen printing isn't a one-squeegee-fits-all world, so it's important to find a sharpener that can properly recondition the types of blade materials you use, whether they're soft and pliable or hard and reinforced, and do so at a speed that prevents press downtime. As always, you should consult with manufacturers about these and other performance specifications so that you can make an informed decision.
"You can have the best press, best dryer, and best exposure unit in the world, but if you don't have a sharp, clean squeegee blade, your print will look bad no matter what," Landesman says. "Screen printing is an integrated approach to decorating. Too often we make the mistake of focusing on just one or two elements of the process. The squeegee blade is one of the critical elements that has been most ignored in the industry."
Squeegees and squeegee sharpeners probably aren't the hottest topics of discussion around your shop's water cooler, but you can bet word will quickly get around when a squeegee-related problem creates a bottleneck on your shop floor. Giving the squeegee the care and attention it deserves will ensure that high-quality prints continue to flow from your presses.
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