I hope everyone has a safe and happy holiday season. This may help you with your home decorations…

In the book, Customer Centered Products, Ivy Hooks and Kristin Farry share some observations about the American culture’s urge to improvise…

We have worked with project managers and engineers who believed that solving the unanticipated problems under the gun was “the fun part of the project.”

In my own experience, I have also met many managers and engineers who would prefer to fix problems through testing, rather than through proper drawings and analysis.

Since we have a competitive edge in the U.S. with our comprehensive product development processes, let’s use them to our advantage. Let’s focus on identifying and solving problems in the design phase, before hardware is built.

Hi Billy,

Based on your description and the drawing, there is not enough information to give you an accurate answer. I would need to see the actual drawing and I need to know how this part fits and functions in the final assembly. Whether this is a final product drawing or a detailed assembly with separate parts at each end will influence how the drawing is dimensioned and toleranced, also.

For example, if this in a single part drawing that has one continuous hole through the full length of the part, then it would be appropriate to specify this hole as a single datum letter and reference it as a primary datum in the feature control frames.

However, if this is an assembly with two separate flange details at each end, then it is appropriate to specify the holes at each end as separate datum letters since they are separate features. However, if the part relies on both of these holes at each end to provide the primary location and orientation of the part, then you would reference them as co-primary A-B datum features in the feature control frames. For example, A-B.

Thanks for writing. It’s a good question. If you’d like to send more detailed information privately, I can give you a more specific answer.

“The economic success of manufacturing firms depends on their ability to identify the needs of customers and to quickly create products that meet these needs and can be produced at low cost.”

- Karl T. Ulrich and Stephen D. Eppinger,
Product Design and Development, 2004

A great book! Should be required reading for all product engineers.

My thought is that functional dimensioning supports Karl’s quote because it protects the customer needs and provides the largest possible tolerance for manufacturing.

We’ve had a lot of interest in our free one-hour GD&T live web public workshop this coming Monday. The “mini-workshop” on Rule #1 and bonus tolerance is from 1-2pm EST.

The course includes sample exercises, and attendees will receive a 10% off coupon to a future live web workshop. Read more about this course.

To take advantage of a GD&T live web public workshop, you need a Windows-based computer, with high-speed internet access (T1 or faster) and a phone line for teleconferencing.

It’s free, so why not try it? If you sign up by 10am Monday, we’ll still have time get you into our class and send you the bonus tolerance problems we’ll be going over. You can try live web training for yourself and learn a little more about GD&T at the same time.

Monday, November 17, 2008
Free one-hour workshop
1 pm - 2 pm EST
(EST - Eastern Standard Time)

American culture’s impatience with time…

Charging into building the product, without sufficient thought into the design, results in a product built to many incorrect assumptions. These assumptions remain unidentified until very late and are costly to fix.

Joshua Hammond and James Morrison

A gem from “The Stuff Americans are Made Of.”

Most drawings that I see require assumptions to interpret. We could make great strides in quality if we just made “technically correct drawings.”

Quality really begins with the drawing.

Have you wondered if live web training is right for you? We’ve had a lot of interest in our new live-web format. If you wonder how it would work for you, you can attend a free one-hour GD&T live web public workshop and find out for yourself.

The “mini-workshop” covers two important GD&T topics: Rule #1 and bonus tolerance. The course includes sample exercises, and attendees will receive a 10% off coupon to a future live web workshop. Read more about this course.

Monday, November 17, 2008
Free one-hour workshop
1 pm - 2 pm EST
(EST - Eastern Standard Time)

No Special Equipment Required
Attending an ETI live web public workshop doesn’t require specialized equipment. It runs in a web browser, and the technology required is commonly found in most homes and organizations.

To take advantage of a GD&T live web public workshop, you need three things:

1. A Windows-based computer
2. High-speed internet access (T1 or faster)
3. Phone line for teleconferencing

Don’t miss this opportunity to try live web training for yourself or your organization, and learn about bonus tolerance at the same time!

The American culture’s acceptance of mistakes…

“We are more loyal to a supplier who quickly fixes a mistake he makes than we are to a supplier who never makes a mistake.”

“Most people in product development assume that mistakes are inevitable. Some mistakes are; however, we often confuse some preventable ones with the inevitable ones.”

Ivy Hooks and Kristin Farry, “Customer Centered Products”

This quote is a real slice of truth.

We so often expect and forgive mistakes on product development programs, but we tend to reward problem solvers and overlook problem preventers.

In my 30 years at GM, I found that there is seldom time to document and analyze the design, but there is always time to solve the issues after the parts are made. I have always felt that most product problems are preventable.

ETI is having a Fall special.

From October 1st to November 30th, if you order a GD&T Trainer Multi-User or LAN version, you’ll receive 50 free GD&T Ultimate Pocket Guides for every $1000 spent on the software.

For example, if you purchase a GD&T Trainer Multi-User for $2595, you’ll receive 100 Pocket Guides ($600 value)

You can receive up to 650 Pocket Guides (a $3900 value) if your company purchases a 10-seat LAN.

The chart at the right shows some more examples. Click on it to enlarge.

Read more about the GD&T Trainer Professional Edition.

Where did the year go? It’s already time to start thinking about next year’s GD&T training plan.

To make it easier, we’ve already posted the whole year’s public workshop schedule online.

In 2009, we’ll be offering the following workshops at our Detroit area headquarters in Westland, Michigan:

- Fundamentals of GD&T 2-Day (ASME Y14.5M-1994)
- Advanced Concepts of GD&T 2-Day (ASME Y14.5M-1994)
- Tolerance Stacks 2-Day (Concept Driven)
- Intro to Statistical Tolerance Stacks 1-Day (Concept Driven)

All workshops include:
- Course materials/handouts
- An official certificate of completion
- Continental breakfast and snacks

There are also bonus materials given out with each workshop.

If you have 5 or more employees who need training, ETI can bring the training to your site, but our public workshops are perfect for companies who have fewer employees to train and for individuals who need training.

Come visit us next year. We’ll get the snacks ready!