MARQUETTE - To the average layperson, tolerance is a personality trait. To those who design and manufacture precision components, it is a critical standard that refers to the variation in dimensions allowed before interchangeable parts become incompatible.

A Northern Michigan University administrator has written Dimensional Management.

The textbook for college-level engineering and technology students also has trade applications for professionals.

Mark Curtis, dean of the College of Technology and Applied Sciences, is a consultant on dimension and tolerance issues related to manufacturing. He also has private industry experience in the area.

"The tighter the tolerance, which means the closer to ideal the dimensions have to be to remain interchangeable, the more expensive it is to manufacture components because there is very little room for error," Curtis said. "You want to have the loosest tolerance - the maximum variation that will still allow products to function and perform correctly. Everything mass-produced deals with dimensioning and tolerancing. It is a significant part of the field and there are nuances to doing it correctly."

While most other books on the subject focus on one or two specific areas, Curtis said his is a comprehensive systems approach to all facets of dimension and tolerance development, analysis, inspection and documentation. It includes more than 125 illustrations and tables and an entire chapter devoted to state-of-the-art computer-aided tolerance techniques.

"This book can be used as both a primer and a handbook for those wishing to optimize the interchangeability of multi-component products," he added. "It may also be used for public seminars and in-plant training sessions."

Dimensional Management was published in May by Industrial Press Inc. of New York. Curtis is the author of two previous college-level textbooks and completed an extensive revision of the Handbook of Dimensional Measurement, 3d Edition.

Prepared By
Kristi Evans
News Director