Dan Gelbart
2 HN recommenders · recommended in 3 months, 2015–2023
12:55 · 114K views · Feb 4, 2013
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.
HN recommends the series as a fascinating, practical course in precision prototyping, with the flexure episode singled out as especially impressive.
3 comments from Hacker News
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]
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
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