Articles

This article makes the case that a core drill is the best tool for opening existing holes. Being designed for the operation, the two-flute indexable drill can produce more accurate holes with less tool wear and breakage than alternatives such as boring bars, drills or endmills.

There are many good reasons a shop might choose to purchase an abrasive waterjet machine. However, as this article explains, many factors must be considered to determine if the investment makes economic sense. The article discusses how and when a shop can adopt AWJ profitably and it explores the possibility of achieving the same results more cost effectively by subcontracting the work to an AWJ specialty house.

Modular fixturing offers a flexible and reusable alternative to dedicated fixtures. This article discusses the benefits of modular fixturing and the types of jobs for which a modular system makes economic sense. A description of typical modular fixturing components and how they are used is also provided.

Solid-carbide drills made with advanced submicrograin carbide are capable of producing holes that meet tight specifications without secondary operations. This article explains how these tools produce reamer-like finishes while offering extended tool life and shortened cycle times. An accompanying article discusses coatings for solid-carbide drills.

When shops crank up the speed, they have to be prepared for the consequences, even if they're milling "easy-to-machine" aluminum.

The economic benefits of high-speed machining can be lost if the wrong tools are used. This article describes the types of solid-carbide drills and endmills that can ensure long-running performance. It also covers the proper handling and setup of these tools.

Researchers at Ohio State University produced contoured cuts with different ball mills to determine the best tool material and coating for the job. This article reports their findings and offers recommendations for extended tool life when milling molds and dies.

Researchers tried bathing inserts in liquid nitrogen to keep them cool while cutting hard-to-machine materials. This article reports the results of this experiment. It shows how the use of cryogenic coolant can keep temperatures down and prolong tool life while machining titanium aluminum vanadium and reaction-bonded silicon nitride.

Improvements in cermet and ceramic inserts have made them a good choice for high-speed milling. This article describes how the compositions and designs of these newer inserts make them tough enough to withstand the punishment of a milling operation while maintaining the hardness that makes them wear-resistant.

Manufacturing customers have begun demanding that their suppliers institute quality-control processes. At the same time, they are expecting their suppliers to adopt more efficient processes so that suppliers can reduce their prices while maintaining profitability. This article discusses these pressures and how even subtier suppliers are being affected by them.

Internal threads can end up undersized because of the work material's properties or because of changes to the hole's dimensions caused by plating or heat-treating processes performed after tapping. This article explains H- and D-limits and how to use them to specify a tap that will produce the right size thread, regardless of any post-tapping operations.

There are some tapping situations that call for a rigid tapholder and some that call for a length-compensating holder. Often the choice depends on the capabilities of the machine and the CNC driving the tap. This article discusses why a machinist might choose one type of tapholder or the other.