Testing & Quality Assurance

Tool chatter is one of the biggest obstacles to effective machining that job nshops face. The author discusses the sources of chatter and offers nsuggestions for minimizing it.

People in the aerospace industry expect a lot from reamers. The author, an nengineer who works for a manufacturer of aerospace components, discusses nstrategies for job shops interested in developing a precision reaming nprogram.

It took years to perfect, but manufacturers finally found a way to economically coat carbide inserts with a diamond film. This article describes the coating process and looks at that companies that are offering diamond-coated tools, the companies that are coating tools for other manufacturers and the companies that are supplying coating equipment. Thick-film diamond is also discussed.

Three different problems can cause a laser to make beveled cuts. As these problems interact, they create distinct patterns of bevel angles that require sophisticated mathematical analysis to sort out. This article discusses an experiment using Fourier analysis to determine which combination of problems caused the cyclical variation that was observed in the measurements of a laser's cutting angle.

For drilling standard holes in metal, there are three primary types of drills: twist, spade and indexable insert. This article discusses the pros and cons of each design and the applications for which each might be appropriate. Factors considered include hole depth, tool cost, drill speed, coolant delivery, tool inventory required, machine tool requirements and expected tool life.