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Variations in Size Measurements by Indicating Gaging Systems



Ralph C. Veale, A Strang, S Merrit, H Chou


The National Institute of Standards and Technology has investigated the efficacy of indicating gaging systems used to measure pitch diameter and functional size of threaded fasteners. Three external systems and four internal systems, representing four manufacturers, were used in the test. Twenty-seven external threads and eleven internal threads were measured. Some of the samples were purposely produced with form errors near and beyond product tolerances. The study shows that when the form errors are outside the product tolerances, indicating gages from different manufacturers give different results and do not always match the values obtained by alternate methods. Results of the tests are presented in tabular form.
Proceedings Title
Proceedings of Measurement Science Conference
Conference Dates
January 17-February 18, 1994
Conference Location
Anaheim, CA


Veale, R. , Strang, A. , Merrit, S. and Chou, H. (1994), Variations in Size Measurements by Indicating Gaging Systems, Proceedings of Measurement Science Conference, Anaheim, CA (Accessed June 18, 2024)


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Created January 1, 1994, Updated February 19, 2017