Log in

2009 - James Bryan - USA

Mr. James B. Bryan

Mr.James B. Bryan is considered by many to be the “founding father of modern precision engineering”.  He began his engineering career in the U.S. Merchant Marines during World War II (1944) as a Jr. Engineer and graduated with a degree in industrial engineering in 1951 from the University of California at Berkeley. He was next employed for several years by Westinghouse and then joined Lawrence Livermore National Laboratory in 1955.  While at Livermore it was his search for ever higher precision in diverse applications that led to the advances in manufacturing that characterized his career.  By the time he retired in 1986 he was known worldwide as the leading practitioner and teacher of precision engineering principles. 

Some of his accomplishments are listed below:  Mr.James B.Bryan was one of the first manufacturing engineers to really realize the importance of temperature in achieving precision in manufacturing.  He has served as the world’s educator on “thermal effects” and played the key role in the development of the seminal American Standard, “Temperature and Humidity Environment for Dimensional Metrology.”  This standard introduces critical concepts such as the thermal error index, the uncertainty of nominal differential expansion, and the thermal variation error (drift test) which form the backbone of ISO machine tool standards almost 40 years later.
He played critical and pivotal roles in the development of the U.S. axis of rotation standards as well as the CIRP unification document.  The technical content of these contributions is now also included in an ISO standard.  Mr. Bryan has over 45 published research papers, a fine record for a non-academic.
Besides his contributions to the written literature, standards and education, Mr. Bryan has made outstanding contributions to the “hardware” of precision engineering.  This really is best illustrated by his work on large diamond turning machines.  This began in the early 1970s with the development of Diamond Turning Machine 1 (DTM1) and proceeded thorough a series of machines of increasing capabilities. These machines were all-liquid showered with temperature control at the milli-degree level and exhibited near 25-nanometer repeatability.

The deterministic theory formulated by him is based on “there is nothing random or probabilistic in the behavior of automatic machine tools or coordinate measuring machines”. This theory have helped many precision engineers to look at any effects in more detailed and recognize the systematic reasons behind any effect .
Other improvements included better tool-setting stations, part trace tests, reversal techniques for machine alignment and, of course, such ideas as the telescoping ball bar. The design and development of the telescopic ball-bar metrology device for the rapid metrological testing of machine tools, subsequently patented and now widely used throughout industry across the world.  Such tests are now in American and ISO standards and used worldwide. He has initiated and driven several important ANSI standards in this field.

Mr. Bryan’s contributions have been widely recognized in the U. S. where he was elected a Charter Fellow of the Society of Manufacturing Engineers, a recipient of their International Medal for Research in Manufacturing, and an Honorary Member of the American Society for Precision Engineering.  He was also featured in Manufacturing Engineering Magazine as a “Master of Manufacturing” and in Fortune Magazine for his contributions to precision.