our digital manufacturing ecosystem
Global Manufacturing Network
People on the ground
3D Printing Materials
Urethane Casting Materials
Digital Manufacturing Resources
Learn about fictiv
2020 State of Manufacturing Report
GD&T 101: An Introduction to Geometric Dimensioning and Tolerancing
How to Accelerate Your Engineering Builds (and Ensure You Get Parts That Fit)
Thank you for subscribing!
The Mars Climate Orbiter infamously disintegrated after its trajectory sent it too close to the planet’s atmosphere, due to a calculation error—an error that could have been avoided if everyone used the metric system.
You might ask, “Well, why not have everyone use imperial units?”, to which I would respond:
You might wonder why the rest of the world uses the metric system. Take a look at the following charts, and see if you can make sense of the imperial conversions:
If you’re still not convinced…
Answer the following:
Imperial: What is half of the diameter of a 1/32″ hole that’s 4 thou oversized?
Metric: What is half of the diameter of a 0.8mm hole that’s 0.1 mm oversized?
*questions from Michael Good.
If you busted out your calculator and began solving fractions, you’ve already added unnecessary complexity to your design. In the end, both answers result in the same distance when rounded—0.017 inches, or 0.425mm. The metric units just reduce the chance of error and, hopefully, keep your future spacecraft intact.