I have to say Amen, Greg. Improper tolerancing is expensive and too few mechanical engineers really learn that in school. Unfortunately, often the young engineer learns tolerancing by doing it incorrectly.
Thanks for your post Charles! We have 4 colleges/universities in the immediate La Crosse, Wisconsin area. While we are actively involved with these institutions through internships and other programs we have not considered a manufacturing focused engineering lecture series. Great idea...thank you for your suggestion.
Charles, I completely agree with you. I'm mentoring and managing several young engineers now and unfortunately they were not taught basic tolerance capabilities for each manufacturing process. I also agree that these basic manufacturing tolerances should be taught in all engineering colleges.
T J McDermott; CAD is a tool for a draftsman (or draughtsman) to create a drawing. Computer hackers create garbage. In my AutoCAD course I was taught what the most frequent mistakes made in CAD were. On my first job in CAD, they were all there. The most common mistake = all drawinga are drawn full size, but they are scaled to fit the paper size to be printed on. The first drawing that I worked on would have needed a 300 ft sheet of paper.
And mechanical engineers (in my experience) do not understand that emergency stop and end-of-travel sensors are normally closed circuits.
I tried to explain to a mechanical engineer that a dimension of 1.000 mm was wrong. I couldn't get him to understand that the default tolerance was +/- 0.0005 mm ! and the proper dimension should have been 1 mm, since it was not a critical part. This engineer also dimensioned a 14 foot long square tube frame as 168.000 inches !
Thanks for the article. I have seen otherwise capable engineers specify ridiculous tolerances over and over again without realizing the cost attached to those tolerances or the assembly problems they produce. I had one engineer that specified a 7.000" part to fit into a 7.000" slot. Not only was the part in no way not critical, but the parts wouldn't fit if one came from the cold warehouse. No matter how hard I tried, he just couldn't understand why it was a problem.
This author should make a tour of some of his local colleges and talk to engineering students who are overloaded with theoretical mechanics classes and don't get ANY exposure to manufacturing. As a result, too many new engineers don't know how to design for manufacturability. This kind if insight is invaluable.
For 3D printing to make the jump from rapid prototyping to manufacturing, engineers will need to find easier ways to move products from their CAD screens to their printers.
Gigabit and PoE are two networking technologies moving ahead in tandem as industrial users power remote Ethernet devices such as IP security cameras at 1,000 Mbps over existing CAT5 cable.
New versions of BASF's Ecovio line are both compostable and designed for either injection molding or thermoforming. These combinations are becoming more common for the single-use bioplastics used in food service and food packaging applications, but are still not widely available.
From Dell / Intel® New Paradigms in Design Work Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013 5
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This radio show will show what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.
To save this item to your list of favorite Design News content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.
Tweet This
2 
