Commonsense is Not a Substitute for a Specification


We just went round and round with a client over a discrepant polycarbonate part. The part is essentially a circular window used in a complex display device. The client and EastBridge Engineering ( are coming down the home stretch on a new product launch.

We performed final inspection of the parts and then supervised packing and shipping. When the parts arrived, our client rejected them immediately.

A slice of our conversation:

Client: “How did you guys allow these to ship?”

EBE: “We inspected the goods using the AQL standard that we agreed on. The parts met all of the written requirements.”

Client: “Well, they don’t look right. Something is off.”

EBE: “What exactly is different?”

Client: “They don’t look the same as the prototype that we built here.

EBE: “OK… What’s the difference?

Client: “They reflect light differently. Don’t you have any commonsense? How could you possibly allow these to ship?”

In the end, we resolved this matter and the client received what he wanted. To get to that point, we needed to be QA mind readers. The part met all of the written standards for mechanical dimensions, light transmission, physical strength, etc. Yet it still didn’t “look right.”

Our engineers are skilled at measuring what’s measurable. We often find creative methods to measure new and difficult features. It’s hard to sort “looks right” from “looks wrong” when there’s no agreed upon standard and commonsense is the baseline screen. We have and utilize commonsense and wouldn’t ship a rolling medical stand that lacked brakes on the wheels (real life example – there were no brakes specified on the drawings).

For new products being born on the fly, we use a collaborative approach to establishing an acceptance standard. Elements related to visual perception and “feel” are the most difficult to pin down. Please bear this in mind and expect to work through a few generations of samples to nail exactly what you have in mind.


Jack Daniels

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