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General Discussion

15175 threads, 282901 comments (44 Viewing)

What is This Round Nut Called?

05/22/2017 by BruceFlorida
I can't find the name or source of the round nut shown below. It is used in the door assembly of an equipment enclosure. The door assembly has a bar w...
Views: 109, Comments: 10
Last comment 05/22/2017 by Nitz

Autonomous Cargo Ships

05/22/2017 by Bayes
I came across this article and thought I'd pass it along. Pretty amazing how quickly autonomous everything seems to be approaching... The world's fir...
Views: 85, Comments: 15
Last comment 05/22/2017 by MR. Guest

History or First Use of the Term 'Slave Cylinder'

05/19/2017 by moon161
Is anyone familiar with the history and origin of the English term in hydraulics 'Slave Cylinder'? I got curious in part because the term used by Merc...
Views: 182, Comments: 26
Last comment 05/22/2017 by SolarEagle

Units Converters

05/19/2017 by James Stewart
We all know how crazy converting pressure units from obscure systems of measurement can be, along with other units of measure, some of which are actua...
Views: 228, Comments: 37
Last comment 05/22/2017 by Dennis R. Levesque
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Commercial Space

1982 threads, 3786 comments (0 Viewing)

Precision Parylene Coating Service

05/11/2017 by Anonymous Poster
From prototype to production, VSI Parylene specializes in precision conformal coating services that deliver consistent, repeatable and high-quality mo...
Views: 48, Comments: 0

Steam Conditioning Valves Corroding Too Fast

05/09/2017 by poot
Does anyone else have a problem with too quickly corroding valves? Since they are made for steam conditioning I'm very "???" as to why they seem to ru...
Views: 25, Comments: 1
Last comment 05/09/2017 by PWSlack
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CR4 Feedback

688 threads, 12047 comments (0 Viewing)
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Section Blogs

Notes & Lines

41 blog entries, 334 comments (2 Viewing)

Troxler's Fading: An Early Optical Illusion

05/22/2017 by Hannes
This blog has occasionally focused on optical illusions and impossible constructs—here’s Part 1 and Part 2 of the impossible object series...
Views: 55, Comments: 1
Last comment 05/22/2017 by Rixter

Digital Music Pioneer and Roland Founder Ikutaro Kakehashi Dies

04/06/2017 by Hannes
Ikutaro Kakehashi, an electronic music legend who founded the Roland Corporation in the early 1970s and pioneered digital music standards in the &lsqu...
Views: 166, Comments: 7
Last comment 04/07/2017 by Hannes
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Defense & Security Technology

114 blog entries, 1653 comments (0 Viewing)

What's DARPA up to in 2017?

05/21/2017 by Engineering360 eNewsletter
The Defense Advanced Research Projects Agency (DARPA) projects that it will make great strides in 2017. From biotech, to vertical take offs and landin...
Views: 94, Comments: 0

NASA Probe Dodges Mars Moon

03/15/2017 by Engineering360 eNewsletter
The mars atmosphere and volatile evolution (MAVEN) spacecraft carried out a rocket motor burn that boosted its velocity by 0.4 m/s. NASA says this is...
Views: 85, Comments: 1
Last comment 03/17/2017 by James Stewart
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The Engineer's Notebook

415 blog entries, 6858 comments (3 Viewing)

Is the Internet Stalking Us?

05/22/2017 by MaggieMc
Since you’re reading this blog post, I think it’s fair to assume you are an internet user, meaning that you’ve likely come across pe...
Views: 34, Comments: 2
Last comment 05/22/2017 by Rixter

Call Your Mother!

05/20/2017 by M-ReeD
Since cell phone use has become widespread, it has changed much of how we conduct our personal relationships. We connect with our friends and family m...
Views: 90, Comments: 0
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WoW Blog (Woman of the Week)

187 blog entries, 535 comments (2 Viewing)

Woman of the Week – Jane Goodall

05/22/2017 by lmno24
Jane Goodall is considered to be the world’s most knowledgeable chimpanzee expert, after spending over 50 years studying their social and family...
Views: 14, Comments: 1
Last comment 05/22/2017 by SolarEagle

Woman of the Week – Dorothea Dix

05/15/2017 by lmno24
Dorothea Lynde Dix was an American activist who worked to change the view of people with mental health issues. She began a vigorous program of lobbyi...
Views: 169, Comments: 4
Last comment 05/17/2017 by roy hammy
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Challenge Questions

352 blog entries, 28476 comments (0 Viewing)

Frustrating Fastballs: Newsletter Challenge (May 2017)

This month's Challenge Question: Specs & Techs from GlobalSpec: Once in a while you may hear a baseball player describe a pitcher’s pitch a...
Views: 1476, Comments: 26
Last comment 05/17/2017 by WilhelmHKoen

Baffling Beer Glasses: Newsletter Challenge (April 2017)

This month's Challenge Question: Specs & Techs from GlobalSpec: Typical beer mugs have thick walls and a thick bottom. This design serves two pur...
Views: 2073, Comments: 27
Last comment 04/25/2017 by The Wolfhound
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45 blog entries, 407 comments (0 Viewing)

Physicists Create a Fluid With Negative Mass

04/20/2017 by Bayes
One of the interesting things you learn early on in physics is that there is nothing in physics that forbids negative mass values. There has long been...
Views: 711, Comments: 51
Last comment 05/02/2017 by James Stewart

NASA Announcement Today on Potential Habitats for Alien Life

04/13/2017 by Bayes
NASA Announcement Today at 2 p.m. EDT NASA will discuss new results about ocean worlds in our solar system from the agency’s Cassini spacecraft...
Views: 127, Comments: 1
Last comment 04/17/2017 by James Stewart
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"On This Day" In Engineering History

242 blog entries, 842 comments (0 Viewing)

April 19, 1906—The Death of Nobel Prize Laureate Pierre Curie

04/19/2017 by MaggieMc
Thinking back to science class, Curie is a familiar name. Marie Curie is a favorite subject in many courses, especially due to organizing mobile X-ray...
Views: 233, Comments: 2
Last comment 04/20/2017 by MaggieMc

February 17, 1864—The Hunley Sinks the Housatonic

02/17/2017 by Hannes
On this day in 1864, the pioneering Confederate submarine H.L. Hunley rammed and sank the USS Housatonic during the US Civil War. She was the first co...
Views: 394, Comments: 2
Last comment 02/18/2017 by ronc
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Editor's Desk

95 blog entries, 362 comments (0 Viewing)

Engineering Job Growth Shows Positive Outlook

04/08/2017 by Engineering360 eNewsletter
The most recent projections from the U.S. Bureau of Labor Statistics concur that jobs in engineering, and other STEM fields, would likely provide the...
Views: 129, Comments: 0

3D-printed Artwork Created on the International Space Station

02/28/2017 by Engineering360 eNewsletter
The first-ever off-world artwork by Eyal Gever demonstrates what humanity can achieve through positivity, and lightens the mood with laughter in space...
Views: 101, Comments: 0
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Animal Science

238 blog entries, 2171 comments (0 Viewing)

Dogs on the Brain

03/13/2017 by MaggieMc
My good friend just adopted a puppy, and with all the pictures coming my way, I have dogs on the brain. Evidently, so do researchers. Two studies were...
Views: 400, Comments: 11
Last comment 03/16/2017 by James Stewart

Kid’s Best Friend

02/01/2017 by MaggieMc
Last week, “A Dog’s Purpose” was released in theaters. The movie—which “shares the soulful and surprising story of one d...
Views: 252, Comments: 15
Last comment 02/05/2017 by JPool
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The CR4 Admin Blog

101 blog entries, 1491 comments (0 Viewing)

2016 Year in Review & Farewell

03/07/2017 by SavvyExacta
It’s a little late for a 2016 year in review but I thought it was a fitting subject for my final CR4 post. You see, I’m moving on to a new...
Views: 421, Comments: 16
Last comment 03/09/2017 by jdretired

Across Five Years (A CR4 Clip Show)

12/28/2016 by HUSH
It certainly doesn’t happen as much today, in the age of streaming services and binge watching. But up until recently the ‘clip show’...
Views: 233, Comments: 3
Last comment 12/30/2016 by Andrew Westman
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What Is It?

69 blog entries, 1869 comments (0 Viewing)

What is It? for February 2

Do you know what this is? Share your guess! Submitted by CR4 user phph001.
Views: 458, Comments: 9
Last comment 02/07/2017 by ronc
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Abe's Blog

5 blog entries, 69 comments (0 Viewing)

Hypatia of Alexandria – Part 3

11/15/2016 by amichelen
(Note: This is last part of Hypatia of Alexandri) Personal life If we have little knowledge of her scientific achievements, we know even less about...
Views: 312, Comments: 35
Last comment 11/19/2016 by TimONeill

Hypatia of Alexandria – Part 2

11/08/2016 by amichelen
(This is the second part of Hypatia of Alexandria) The ideas developed by the Pythagoreans represent a solid contribution to the scientific knowledge...
Views: 213, Comments: 1
Last comment 11/10/2016 by Bayes
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Rockaholic Adventures

50 blog entries, 611 comments (0 Viewing)

Morphology of Olympus Mons

12/05/2016 by Shawn
After discussing the morphology of Olympus Mons I felt compelled to share my intuition of the shield volcanos existence and morphology strictly throug...
Views: 251, Comments: 5
Last comment 12/08/2016 by Shawn
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Great Engineers & Scientists

145 blog entries, 500 comments (0 Viewing)

The First Lady of Structural Engineering

11/28/2016 by MaggieMc
Elmina Wilson is widely regarded as “the first lady of structural engineering.” Born on September 29, 1870, Elmina came from a family of w...
Views: 347, Comments: 1
Last comment 11/30/2016 by gideon
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65 blog entries, 579 comments (0 Viewing)

The San Fran Skyscraper with a Six-Inch Slant

09/28/2016 by HUSH
Skyscrapers are a lot more to a city than just real estate. They represent financial prosperity and engineering acumen. They transform the identity of...
Views: 845, Comments: 20
Last comment 01/25/2017 by MR. Guest
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TechnoTourist’s Engineering Expeditions

83 blog entries, 490 comments (0 Viewing)

A Piece of Ireland in Texas

08/23/2016 by joeymac
Everyone knows that kissing the Blarney Stone over in Ireland is supposed to give a person the gift of gab and eloquence of speech. I was fortunate en...
Views: 495, Comments: 7
Last comment 08/25/2016 by joeymac

Amsterdam's Canals

07/13/2016 by joeymac
When I went on my European trip another stop I made was to Amsterdam, and I was fascinated by all of the canals and bridges connecting to everything....
Views: 266, Comments: 0
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Other Blog Entries of Interest

Caption This for 3/31/2017

03/31/2017 posted in Caption This!
by lmno24
This week's image: Thanks to Nigh for the submission! Keep in mind we are always looking for submissions, send us photos anytime. Be sure to vote...
Views: 523, Comments: 38
Last comment 04/07/2017 by Randall

Caption This for 3/24/2017

03/24/2017 posted in Caption This!
by MaggieMc
This weeks image: Be sure to vote for your favorite caption! Thanks to Nigh for the submission, we're always looking for more!
Views: 676, Comments: 85
Last comment 04/06/2017 by szwasta

Caption This for 3/17/2017

03/17/2017 posted in Caption This!
by lmno24
This weeks image: Be sure to vote for your favorite caption! Thanks to user sptilton for the submission.
Views: 403, Comments: 20
Last comment 03/20/2017 by Mikerho

Caption This for 3/10/2017

03/10/2017 posted in Caption This!
by MaggieMc
This week's image: Be sure to vote for your favorite caption! Thanks to Solar Eagle for the submission.
Views: 533, Comments: 49
Last comment 03/14/2017 by Mikerho

Caption This for 3/3/2017

03/03/2017 posted in Caption This!
by lmno24
This week's image: Be sure to vote for your favorite caption! Thanks to user Nigh for the submission.
Views: 629, Comments: 52
Last comment 03/10/2017 by MaggieMc