2 HN users recommended this lecture2 months2015–2023score 2.5
Years with an HN recommendation, 2007–2026
HN recommends the series as a fascinating, practical course in precision prototyping, with the flexure episode singled out as especially impressive.
Part 10 of Dan Gelbart's prototype-building lecture series, covering flexures: flexible joints that give precise, frictionless motion. It shows how a cheap piece of aluminum can become a nanometer-accurate mechanism.
“He starts off with a $10 piece of aluminum that took maybe an hour or two to make” (HN, 2015)
Part 10 [1] of his prototypes series also features incredibly impressive precision. He starts off with a $10 piece of aluminum that took maybe an hour or two to make, and is completely accurate down to nanometers. I worked in a nanotech lab with an electron microscope, and the idea that you could make a mechanical device that could accurately move a few pixels on my screen blew my mind. I thought I was hot shit with all my electrons and magnets... nope. Dan's flexure is so sensitive that radiative heat from his hand moves the end stage 100x more than mechanical input. You could move it by shining a laser pointer at it. Insane. The final part [2] is also very neat, and starts with a really remarkable demonstration of stiffness. [1]: [this video] [2]: [link]
Shows nanometer-accurate flexure made from cheap aluminum, remarkably sensitive.
I found Dan Gelbart's series about building prototypes [1] to be fascinating, and helpful. I was especially impressed with his video about flexures.[2] [1] [link] [2] [this video]
Fascinating, helpful prototyping series; flexures episode especially impressive.
In the industry flexures are considered to have 'infinite' life if they are correctly designed and if you stay well within the working parameters. If you stay within about 2/3rds of the elastic range it lasts forever. Dan Gelbart: [this video]
Cited as source on flexure design and fatigue life.
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