b'Anything that needs traceability, they will put an engraving on it.A Happy Medium In the old days, the coatings were pretty thick be-cause they were CVD coatings, White said. Now, the modern PVD coating is thin: 1 to 2 m (0.00004" to use a precision tool because they are used in produc- 0.00008"). You can put it on a really sharp tool and still tion and prototype applications to create logos or in- keep a sharp cutting edge.formative markings on a workpiece, and those are usedHe said the toolmaker uses Platit coating equipment for visual recognition, he said. So its important toto deposit SCTs AlTiN+, or AlTiSiN coating, which in-maintain a high level of consistency and minimize varia- cludes silicon in addition to the recipes typical ingre-tions from part to part. dients of aluminum, titanium and nitride. Coated tools End users frequently engrave with a ballnose or an- are applied mainly to engrave ferrous materials. But be-other type of endmill, but even tiny ones wont neces- cause the heat and friction generated when machining sarily achieve the required result when the engraving isenhance an AlTiN-based coatings protective charac-difficult if not impossible to see clearly with the nakedteristics through oxidation, coated tools are also effec-eye. tive for engraving nonferrous materials, such as plas-The challenge with a precision tool like this is find- tic and aluminum. This enables an end user to engrave ing the applications where someone simply cant do itboth aluminum and steel workpieces with the same with a conventional tool, Cetkovic said. If youre pro- tool.ducing a workpiece that ends up in the human bodyIn contrast, because BIG KAISER Precision Tooling and you need to engrave it with your companys namedoesnt coat tools smaller than 0.2 mm (0.008") in di-or a serial number, thats where a tool like this is criticalameter, Cetkovic said all the companys engraving tools because you can create a very consistent but very smallare uncoated.feature on the workpiece. They are far below the minimum for a coated tool, National Sales Manager Todd White of Scientific Cut- he said.ting Tools Inc. concurred. He said a microengraver withLikewise, all of Kyocera Precision Tools standard a flat at the bottom, for example, provides better en-graving definition than a ballnose endmill, which gen- Engraving tools and engraved workpieces are shown.erates a radius form in the workpiece.It might not stick out as well, he said about an en-graving made with an endmill.The Simi Valley, California, tool manufacturer offers single-flute engraving tools with tip diameters from 0.127 mm to 0.381 mm (0.015") and included angles of 30, 40, 60, 90 and 120.Slick and SharpTo minimize the amount of workpiece material that sticks to a tool, White pointed out that SCT provides a polished finish on the face of its engravers.In addition, cutting edges must be sharp to create a clearly visible, consistent engraving. That is generally not an issue for uncoated engraving tools but can be for coated tools if the appropriate coating technology isnt employed.about the author Alan Richter is editor-at-large for CTE. Contact him at [email protected] 2020Engraving.indd 40 8/17/20 11:03 AM'