Dimensional Management, many times, is fragmented, which inhibits effectiveness. It must be a holistic process that, like a Sherpa, keeps all the stakeholders of interest on the same path and not going it alone.

It’s part of your APQP process; if not, then it should be.…

Dimensional Management starts at design conception and continues through the lifecycle of the product.

The GD&T strategy begins at the first thoughts of function. And the primary function every part or assembly must do is assemble. Regardless of what other function a part must perform, if it won’t load and mount in the packaged environment, then you already have a build issue. Engineering a capable, functional datum scheme that provides an entirely constrained but not over-constrained part or assembly must be agreed upon early. The mating component features must be decided as soon as possible. Asking for changes later may not be possible and would drive extended cost that programs cannot afford.

The dimensional strategy, once defined, will be reviewed, and the design validation confirmed using dimensional studies (VSA, RSS stacks, etc.) supporting the plan and proving it’s feasibility.

The dimensional management process supports the manufacturing tooling, process development, as well as the dimensional quality plan that supports tool validation, PPAP approval, and continuous conformance as well as supporting problem-solving activities, should it be needed.

Dimensional management is not an afterthought, as it must begin from the onset of design and applied throughout your manufacturing and quality systems. Using parts of the plan or segregating the teams and not properly collaborating will limit the potential for your success. Putting the program at risk and or potentially inducing unwanted cost.

One approach is to teach every engineer GD&T and have them apply it as necessary. There are several failure modes to this approach. One is that no two engineers, even when trained by the same person, will approach solutions the same. If both engineers are working on a common commodity, they will have different strategies that may require unique tooling, gages, processes, and mitigate the potential for flexibility.

Our approach is to have one commodity knowledgeable person be the Dimensional Manager. Providing his one strategy and assuring all stakeholders not only understand the dimensional strategy but are also properly applying it in there tooling, gages, processes, and quality plan.

If you are interested in further understanding of how I view Dimensional Management or would like to have your process reviewed, please contact me and let’s get ahead of the game.