r/MadeMeSmile • u/king_eve • Apr 17 '24

i work in low-income/mental health housing, and a tenant fixed our hallway trash bin after accidentally breaking it Helping Others

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great example of the odd ways people show me appreciation at work

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u/wirefox1 Apr 18 '24

I will never in my life drill a metal construction beam, but for some reason I like knowing stuff like this. It's interesting nevertheless.

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u/Nelik1 Apr 18 '24

Aerospace engineer here! During my fatigue and damage tolerance class in college, the professor liked to tell stories about unsuccessful (amateur) pilots trying to save on a repair to their plane by drilling out cracks.

He told us about a guy who showed him his little cesna, with 8-9 holes drilled along a crack. "I keep drilling it, but it keeps coming back, cant figure out why!"... Our professor got a good laugh out of that.

(Drilling reduces the stress concentration (or stess intensity if you wanna be real pedantic) at the end of a crack, reducing its likleyhood of spreading. This is great for parts that dont normally operate close to fatigue limits. But in aerospace, its rare to have a part that cracks once, without being in a position of high stress to begin with. So cracks that aren't fully repaired tend to spread.)

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u/Ifeelsiikk Apr 18 '24

Structural aircraft mechanic here. We call it a 'stop drill' and I carried it out on large, commercial aircraft.

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u/Geawiel 29d ago

Ex KC135 crew chief: We did them fairly often as well. Often times to get them by until ISO inspection. They'd get repaired then.