Machining

This article reviews the causes of skin irritation suffered by some shop workers, with special attention paid to skin conditions that result from poorly maintained metalcutting fluids. The article also discusses the factors that can aggravate skin problems and suggests ways that workers can protect themselves from skin irritants.

Although machinists are using cermet and ceramic cutting tools for an increasing number of applications, they have been slow to adopt them for boring. This is beginning to change, however. This article describes some of the ways a boring operation can benefit from the use of these tools.

This article traces the changes in countersink design and materials that have been made to satisfy the demands of the aerospace industry. The advantages and disadvantages of different types of modern countersinks are discussed.

Traditional tap/drill charts recommend drill diameters for each size of tapped hole. But, according to this article, these recommendations are based on the size holes that were typically produced by less-accurate tools and processes used in the past. This article suggests guidelines for producing holes that will, in turn, produce correctly sized tapped holes.

By recycling used metalworking fluids, shops can realize considerable savings in fluid and disposal costs. This guide takes the reader through the fundamentals of fluid recycling and management. Excerpted from a manual on the subject, the piece covers both the care and cleaning of fluids and fluid-handling equipment.

The more sophisticated die-sinker EDMs on the market today possess enough intelligence to monitor cutting conditions and make necessary adjustments on the fly. This article describes the technology that drives these smart machines and the "fuzzy logic" they use to maintain an optimal spark.

Modern control technology makes extremely fast milling speeds possible. But the top speed can only be as fast as the slowest link in the chain between controller and machine. This article looks at some of the bottlenecks that can prevent a mill from running at full speed.

CBN grinding wheels offer the promise of higher productivity and longer wheel life, but they must be carefully maintained with dressing routines that differ from routines for standard wheels. This article details the techniques and tools needed to perform CBN wheel dressing effectively and economically.

A CNC tool grinder connected to an automated loading unit can be programmed to grind tools during a shop's off hours. This article discusses the planning and preparation that are necessary to set up an unattended run.

This article describes the apprenticeship program and other activities that toolmaker Komet of America is pursuing to bring new people into the metalworking industry as machinists. The company has met with some success working with the Tooling & Manufacturing Association and a local high school.

This report details the results of a test of graphite electrodes. The test compared the performance and machinability of three graphite grades, ranging from an inexpensive coarse grade to a relatively costly ultrafine grade.

Dual-spindle turning centers allow shops to combine several processes into one setup. This article describes a typical dual-spindle turning center's configuration and capabilities. A common scenario is given showing how such a machine might be used to reduce cycle times.