HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
Comments
View Comments: Newest First|Oldest First|Threaded View
Scott Orlosky
User Rank
Platinum
Re: Great article
Scott Orlosky   1/27/2013 12:03:05 AM
NO RATINGS
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.

Dave Wittenberg Mcloone
User Rank
Iron
Re: Great article
Dave Wittenberg Mcloone   1/21/2013 3:35:14 PM
NO RATINGS
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.

Greg M. Jung
User Rank
Platinum
Re: Great article
Greg M. Jung   1/20/2013 10:34:33 PM
NO RATINGS
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.

GlennA
User Rank
Gold
Re: default tolerances
GlennA   1/20/2013 8:33:31 PM
NO RATINGS
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.

TJ McDermott
User Rank
Blogger
Re: default tolerances
TJ McDermott   1/20/2013 3:18:27 PM
NO RATINGS
Your engineer didn't change the default tolerance in his CAD software.

This sin is most common coming from electrical engineers who don't normally design the mechanical side of things.

To their credit, electrical engineers have to deal with mechanical types not understanding PNP/NPN circuitry when it comes to sensors.

GlennA
User Rank
Gold
default tolerances
GlennA   1/19/2013 9:12:03 PM
NO RATINGS
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 !

tekochip
User Rank
Platinum
Over Specified
tekochip   1/18/2013 7:09:44 PM
NO RATINGS
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.

Charles Murray
User Rank
Blogger
Great article
Charles Murray   1/18/2013 4:58:12 PM
NO RATINGS
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.



Partner Zone
Latest Analysis
It's been two years since the Mac Mini's last appearance on iFixit's teardown table, but a newly revised version joins Apple's lineup this week.
More often than not, with the purchase of a sports car comes the sacrifice of any sort of utility. In other words, you can forget about a large trunk, extra seats for the kids, and more importantly driving in snowy (or inclement) weather. But what if there was a vehicle that offered the best of both worlds; great handling and practicality?
Kevin Gautier of Formlabs describes the making of a carbon fiber mold for an intake manifold, using a $3,300 3D printer, during Medical Design & Manufacturing Midwest.
Science fiction author Isaac Asimov may have the best rules for effective brainstorming and creativity. His never-before-published essay, "On Creativity," recently made it to the Web pages of MIT Technology Review.
Much has been made over the potentially dangerous flammability of lithium-ion batteries after major companies like Boeing, Sony, and Tesla have grappled with well-publicized battery fires. Researchers at Stanford University may have come up with a solution to this problem with a smart sensor for lithium-ion batteries that provides a warning if the battery is about to overheat or catch fire.
More:Blogs|News
Design News Webinar Series
10/7/2014 8:00 a.m. California / 11:00 a.m. New York
9/25/2014 11:00 a.m. California / 2:00 p.m. New York
9/10/2014 11:00 a.m. California / 2:00 p.m. New York
7/23/2014 11:00 a.m. California / 2:00 p.m. New York
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Oct 20 - 24, How to Design & Build an Embedded Web Server: An Embedded TCP/IP Tutorial
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Class: 10/28-10/30 11:00 AM
Sponsored by Stratasys
Next Class: 10/28-10/30 2:00 PM
Sponsored by Gates Corporation
Next Class: 11/11-11/13 2:00 PM
Sponsored by Littelfuse
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service