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Comment by 8eye | Hacker News Reader

i remember listening to a lecture on this in my business class before all these issues, we watch a video on outsourcing and how this is the first of their planes that used an advanced supply management system to outsource. traditionally boeing did most of their major sourcing from mainly the united states, the united states has some of the strictest air safety laws in the world so previously it was nearly impossible to source overseas due to supply chain parts reliability. guess that is still the case then

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Back on the 757, Boeing outsourced a lot of subassemblies to Japanese companies. We engineers liked them, as they produced very, very good parts.

Though personally I liked Saginaw Gear the best, as they did the forgings for the stab trim jackscrew, and made the best of the best.

Can you share what makes forged parts better than others? Wouldn’t it simply be better molds or finishing I suppose? I’m only familiar with forged gun parts and even the cheapest forged parts look and function as good as the expensive ones, but then again going bang is easier than keeping people in the air through crazy stresses and heat and cool cycles.

Forging orients the grain structure of the metal in a predictable manner. It also helps remove voids.

Generally, a forged part is going to be free of the voids and surface defects of a casting, and waste less material than cutting from an rolled or extruded piece of stock.

I understand what forging is, I was just asking what made their forging better than others is all.

Do you mean why Saginaw is the best? Because Boeing didn't have problems with defective parts coming from Saginaw. The Saginaw people knew what they were doing. Boeing didn't trust anyone else, as these are critical parts. I wish I could have taken one of the jackscrews home and mounted it over the fireplace like some people mount a sword :-)

Saginaw is Chinese owned and has a interesting history:

"GM in 1999 spun off its parts group as Delphi Automotive including Saginaw Steering. Saginaw Division was renamed Delphi Steering"

"With Delphi entering a lengthy bankruptcy proceeding, GM purchased Delphi Steering through their subsidiary, GM Global Steering Holdings LLC, in 2009 and renamed the company, Nexteer Automotive"

"Nexteer was acquired by Pacific Century Motors on November 29, 2010"

"Originally, Pacific Century was a subsidiary of E-town, the Beijing municipal government's investment company, and Tempo Group, a Chinese car component manufacturer."

"In March 2011, AVIC Automobile Industry Holding Co., a Chinese state-owned parts manufacturer, purchased a 51 percent interest in Pacific Century Motors."

Can you extract one from one of the dead 757s in Arizona?

Forgings are 3x stronger than the equivalent casting. I'm not a materials science guy, so my knowledge of the details is a bit vague, but the grain of the metal follows the shape in a forging.

When I amped up the horsepower of my Dodge, I replaced the cast bell housing with a forged steel one, because I like my feet. (I've seen pictures of the flywheel coming through the side of a car.) All the spinning parts in the engine were replaced with forged ones, too.

I think that video was not correct then or they talked about something else because Boeing has outsourced critical parts whenever necessary at least since the 80s. I think the parts came mainly from Germany and Japan but I'd have to look it up.

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