William Tandler

William Tandler’s professional experience includes three years at the Hewlett Packard R&D laboratory in Palo Alto, CA, where he helped develop a quadruple mass spectrometer; five years with the laser manufacturer Coherent Inc. as international marketing manager; followed in 1975 by the founding of Multi Metrics Inc.

Tandler is currently a member of the ASME Y14.5.1 Mathematization Committee; a subject matter expert for Working Group 4 of the ASME Y14.5 standard focused on datums; and has been a contributor to ISO TC213 in the realm of datum reference frame construction.

Thu, 10/29/2015 - 22:00
Clarifying GD&T A glossary of key terms to better understand geometric dimensioning and tolerancing
Thu, 10/29/2015 - 22:00
Editor's note: The original version of this “classic” article by William Tandler first appeared in Quality Digest media in June 2008 and was based on the ASME Y14.5 1994 standard. Updated here to address the ASME Y14.5 2009 standard, it is an…
What’s New in the Y14.5 2009 GD&T Standard There is much of great interest and benefit in the new standard.
Mon, 08/10/2009 - 05:00
Formatting constraints prevent us from formatting this article in a way that might make it easier for the reader to understand. If you have problems understanding the web version of this article, download a pdf by clicking here.
--Editor 1…
The GD&T Encoding Process—Final Steps Smart GD&T workshop No. 8
Wed, 05/07/2008 - 22:00
Encoding the mating flange:
In Workshop No. 7, we used Smart GD&T processes to encode the operation, assembly, and other functions of a flange. In this workshop, we take a deeper look at the mating aspect of the game by encoding the…
The GD&T Encoding Process Smart GD&T workshop No. 7
Wed, 04/09/2008 - 22:00
T he actual purpose of GD&T: It’s common to think that the primary purpose of GD&T is to unambiguously communicate design intent to manufacturing and inspection. In fact, the most important objective is to ensure that what we…
Establishing Datum Reference Frames Smart GD&T workshop No. 6
Wed, 03/12/2008 - 22:00
What’s a datum reference frame?
As discussed in workshop No. 5, datum reference frames (DRF) are coordinate systems, and preferably—at least to start with—Cartesian coordinate systems. As we know, coordinate systems serve to orient and…
All Those Datum Things Smart GD&T workshop No. 5
Wed, 02/13/2008 - 22:00
As we know, GD&T is a symbolic language with which to specify permissible limits of imperfection in manufactured parts, namely limits that maximize the parts’ operability, assemblability, and affordability. It’s complex only to the extent that…
Tolerance Zone “Size” and “Mobility” Modifiers Smart GD&T workshop No. 4
Wed, 01/09/2008 - 22:00
Back in the 1940, when Stanley Parker, Mr. GD&T, decided it was time to create a set of tolerancing tools that realistically dealt with reality, two objectives were near the top of his list. The first was to find a way to encode the fact that as…
The Perfect Imaginary World of GD&T Smart GD&T workshop No. 3
Wed, 12/12/2007 - 22:00
Our original plan for workshop No. 3 was to discuss what are generally referred to as material condition modifiers, namely the encircled letters “M,” “L,” and “S” which sometimes follow tolerance values and sometimes follow datum-feature labels in…
Interpreting GD&T-Decorated CAD Models Smart GD&T workshop No. 2
Wed, 11/14/2007 - 22:00
Continuing with our analysis of the Greatest Design Tool ever, our objective in this article is to take a detailed look at the structure and contents of feature control frames to demonstrate that they represent “encoded” information which may…
Is GD&T a Lot of Gol-Derned Trouble? Yes, and worth it—Smart GD&T workshop No. 1
Wed, 10/10/2007 - 22:00
What is GD&T, anyway? The Greatest Design Tool ever, or a whole bunch of Gol-Derned Trouble? Actually, geometric dimensioning and tolerancing is both, and worth every penny. Only with the help of GD&T can we test and guarantee the…