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The case of the Pentagon’s $45 bolt

Here's an interesting thing. It starts with a typical outraged Twitter post:

Now suck in your gut and read this very long—but fascinating!—reply from Greg Koenig about why bolts like this cost so much and are worth every penny:

Fun fact.

In the outskirts of Portland is a nice little shop in an anonymous industrial park. You walk in to a little foyer with a folding card table and 9 thick, vacuum sealed Mylar bags, each about 1' long and 4" in diameter. They are sitting on top of about 70 pages of paperwork. This is the entirely daily production of this facility.

Inside are a bunch of old Mori Seiki NLX lathes — the old ones, before Mitsui bank let Dr. Mori train wreck the company with the DMG merger. Aside from a little wear on the interior paint, the 7 lathes look like they just came out of the showroom. In fact, the whole place looks like a machine tool showroom — spotlessly clean, with a thick, perfectly level urethane floor that a product photographer could use as a mirror white background plane in an Apple ad.

There are a few big things in our lives that are literally held together with a couple of fasteners. One example; every Boeing and Airbus engine is held onto the wing by only 2 bolts, and this is the shop that makes them. Boeing and Airbus both require multiple suppliers for critical components, so this is not the only shop that makes these bolts, but the nearest competitor is in Seattle (close to Boeing, but far enough away that the Cascadia Subduction Zone quake won't take both out).

The shop bay next door is equally clean, but contains a vacuum furnace and the most through inspection lab I've ever seen. X-ray and magnetic particle inspection, CMM, optical comparators. In the corner is a cherry red custom painted Lista cabinet where raw blanks are stored. An identical Lista cabinet in Green is at the opposite side of the shop. Raw material comes in, gets inspected, heat treated, inspected again, and moves from the Red to Green cabinet, collecting about half the paperwork along the way.

The blanks take about 3 days to go from a cylinder of Sandvik or Thyssen-Krupp steel into a bolt. One machine, the oldest, is used to rough the blank into a pair of concentric cylinders, the second oldest machine roughs the hex head, before the bolt is stress relieved and allowed to rest for 36 hours. Another machine finishes the hex and applies chamfers, these are final surfaces.

The final step is the threads, where things get interesting. They are cut in 3 steps; roughed, semi-finished, and finished. The secret sauce here is that a new insert is always used as the semi-finisher, and the semi-finished state is very very carefully measured to compensate that exact insert. The final finishing pass is taken in one (surprisingly healthy) hit using the data from the semi-finishing pass to be on-dimension within about 2µm. The key insight they had is that you get a better surface finish off of a tool that has already taken a couple of cuts. The threads look like you wrapped a mirror around a spiral staircase; their process is so dialed-in that their work competes with thread-grinders for dimensional and surface quality. Even so, just before inspecting with old-school thread wires at the machine — the guy running the lathe spins it at about 500rpm and reaches in with a Bright Boy stick and touches them up, runs his fingers over them, and gives them the most important QC they'll receive. This guy has been on this machine for 15 years; nearly every aircraft passenger aircraft in the sky is held together by at least one bolt that has passed his touch inspection.

Of course, the engineers in Renton or Toulouse won't just accept that Mitch in Gresham touched this bolt so it is good... so whole reams of paperwork are geared by regularly calibrated Zeiss metrology gear that does a complete dimensional inspection, another magnetic particle inspection (3 in total), and an X-ray. Having said that, Mitch rejects more than Zeiss does (about 2-3%).

You want to pay more than $45 for each of these bolts.

Now, the particular bolts Koenig is describing actually cost $2,300: as he puts it, $100 for the bolt and $2,200 for the inspection paperwork. But the bolt in the picture is its little cousin. It doesn't hold engines onto wings, but it's an airplane bolt with similar quality requirements.

This is not the explanation for every high-priced milspec component. But you should know which is which before you shoot off your mouth.

63 thoughts on “The case of the Pentagon’s $45 bolt

  1. QuakerInBasement

    "This guy has been on this machine for 15 years; nearly every aircraft passenger aircraft in the sky is held together by at least one bolt that has passed his touch inspection."

    And this MFer gonna get paid. No one should begrudge him.

    1. Ogemaniac

      I work with a very complex piece of 40 year old equipment who OEM has been out of business for twenty years. There’s one guy on earth, a former OEM employee, that has made his career refurbishing these million dollar beasts and keeping them running.

      His $325 fee for a video conference is a bargain. Press that button. Tell me the voltage across C9 and C8. Now flip that breaker on and off. There, you are set. Just had to discharge a capacitor…etc.

  2. Total

    Yes, we should definitely adopt the position that military spending is efficient just because the Republicans are on the other side.

    1. Laertes

      Don't know what article you're responding to, but the one above is about adopting the position that certain parts may be more expensive than the ones you pull out of the bin at the hardware store downtown for reasons that aren't apparent to readers who consult only hostile sources and/or their own preconceptions.

      Sure sounds like the article you're responding to sucks, though. Maybe link it if you get a minute.

    1. J. Frank Parnell

      I suspect Koenig got this wrong. A quick Google check says engines are typically mounted at two points, one forward and one aft, but each "mount" uses several bolts. On the CFM56 engine used on an Airbus A320 each mount uses 4 bolts, or 8 bolts total. The mounts also include shear pins so that under extreme loads the engine will break loose without tearing the wing off.

  3. JohnH

    That's fine. Even interesting (and enlightening). But I'll just repeat it's not needed. I'd be delighted to see excessive spending subject to crit and cuts, most especially defense spending. Seems to me that libtards like me have been complaining about the military and its spending since the Vietnam War, maybe longer, and it's always been the GOP resisting (and cashing in). But , again, so what? It won't make us eliminate the Defense Department, much less government.

    And anyway, what you see in social media is no way to run a country. It gave us Trump this on Election Day, but that's hardly a recommendation.

    1. J. Frank Parnell

      A big problem confronting today's aerospace industry is counterfeit parts. It's cheaper to dumpster dive behind the factor and rescue reject parts and then counterfeit all the paperwork than to make the real thing. Likewise one can just use an undocumented offshore bolt and counterfeit a provenance. All the inspections and certification seems extreme, but when a wing comes off and hundreds of people die there is hell to pay.

    2. Jim B 55

      You have to remember that for the Red States, military expenditure is military Keynesianism. Without it, their states would collapse economically.

  4. dilbert dogbert

    A lot of the paper work and inspections are driven by our real rulers. The personal injury lawyers.
    The boss needs to look into the Federal Acquisition Regulations.

    1. Dave_MB32

      You make it sound like a bad thing that there's at least *someone* who's holding people responsible for following the rules and regulations and making certain that they're doing what they're supposed to.

  5. J. Frank Parnell

    I suspect the threads on the bolt in question are not "cut", but rather are "rolled", as this produces a better thread form with a hardened surface and without the stress concentrations that a cutting tool would produce.

    1. Steve_OH

      You would think so, but the process described, involving [carbide] "inserts," is clearly a cutting operation rather than a rolling operation, which uses dies rather than inserts.

  6. SeanT

    Your first mistake was reading Harrison Krank

    a guy who literally tweeted a few months back
    "Call me radical but we should hire based off merit "

    who
    wait for it
    works for his father's financial services firm

      1. emjayay

        From the pilot episode of All In the Family:

        Archie: If your spics and your spades want their rightful share of the American dream let them get out there and hustle for it just like I did.

        Meathead: Yeah but Archie you are forgetting one thing - you didn't have to hustle with a black skin....are you telling me that the black man has had the same opportunity in this country as you?

        Archie: More. He's had more. I didn't have no million people out marching and protesting to get me my job!

        Edith (agreeing with Archie): No, his uncle got it for him.

  7. Doctor Jay

    The simple answer to this kind of thing is to let them do it, bet against them in some futures market, and wait for the profits to roll in. And we'd do this if not for an inconvenient thing like a conscience.

    Or, let's look at this a different way. It might be the case that a bolt of identical quality could be made for half the price. How much difference would that make? How much of my tax bill could be refunded based on the savings? Would it even be a penny?

    And now I'm wondering if some enterprising YouTuber couldn't do a side-by-side video with the custom bolt on one side, and a hardware store bolt on the other. If the quality difference is real, you should be able to see it, right? Not just get told by some profit-seeking jerkoff who is trying to skim off the taxpayer's back, right?

    1. Steve_OH

      If the quality difference is real, you should be able to see it, right?

      Not it the difference is in heat treatment. You can't look at a bolt and tell if it's going to fail from fatigue after 50 cycles vs. 50,000 cycles. Likewise for stress-induced microfractures from the machining process.

    2. lawnorder

      The only visible difference will be that if you subject both bolts to equal loads, increasing until something breaks, you will see that the hardware store bolt breaks first.

    3. Adam Strange

      Back before Sears went out of business, I bought a hex wrench from them for removing a stuck socket head cap screw.
      As I turned the wrench, the screw remained stationary but the hex wrench twisted into a spiral which made it look like a tap extractor.

      Steel quality and heat treating are not something that you can see, just by looking.

      1. Crissa

        I just got some drill bits off Amazon which just... unrolled. Their heat treatment was inconsistent so they had soft spots.

    4. golack

      Interesting proposal. You probably could buy different grades of bolts, as well as bolts of different materials, and easily see differences. A high grade hardware store bolt and a truly mil spec bolt? Maybe with an electron microscope or some of the test equipment talked about in the article. Testing failure over time/cycles, takes, well time. And you need to test a lot of them. Maybe a low percentage of high grade hardware store bolts will fail significantly sooner than average whereas mil spec bolts would have that in the low fractions of a percent.

    5. kaleberg

      Back in the 70s I had a friend who worked on Xray satellites. One day, there was a lot of excitement in his lab. Someone had found a burned out MILSPEC transistor. As my friend pointed out, odds are no one had seen one and likely no one would ever see the like again. I remember MILSPEC transistors cost maybe 10x regular transistors which cost a lot more than the Radio Shack happy bag of ten or maybe 25.

      Another thing to consider when estimating the cost of parts for military equipment, a full lifetime of replacement parts is budgeted as part of the cost of each unit. If a plane or tank or heavy gun is going to last 20-30 years, there has to be a 20-30 year stockpile of replacement parts. Gearing up a factory to produce them would be even more expensive than maintaining an inventory. Needless to say, this gets us some ridiculous prices for what seem to be ordinary items.

  8. miao

    Once I had to buy some special plastic tubing for a project I was on. I found I could buy it in "consumer" grade, which I did, because the medical grade cost 10x more. Because of all the documentation requirements, showing it would not kill people. Some times some extra cost is worth it.

  9. bbleh

    But you should know which is which before you shoot off your mouth.

    Hahahahaha! Stop, please! Yer killin' me!

    Let FACTS get in the way of OUTRAGE? Actually KNOW what you're YELLING about?! Do you realize who was just elected President, and who voted for him, and whom he's nominated to head nearly every Cabinet department?

    Buddy, "facts" are Out. Loudmouthed outrage is In, and it SELLS! That's how you build a Personal Brand, and there's nothing more important than Personal Brand when you're working for that sweet, sweet cash! (And really, is there ANY measure of our value as Americans more important than how much cash we have?) Also, "facts" are BORING, and finding them out takes TIME that can be better spent, yes, building Brand. Why bother?

    Know what you're talking about. Ha!

  10. chuchundra

    Many years ago our local defense contractor Grumman, when they were still an independent a going concern, got gigged by some congressional military waste investigation. Turns out they were charging $600 a throw for ashtrays for the F-14 Tomcat. Sounds like a lot of money for an ashtray, but it turns out that they F-14 was never designed to have ashtrays, so when some military bigwig requested them they had to be custom designed and machined out of aircraft-grade aluminum, each one taking hours of skilled labor.

    In response to the outrage, they lowered the price to $50 and vowed never to make ashtrays for anyone ever again.

    1. rick_jones

      I could see cup holders. I could even see trays. But ashtrays? Why the hell would pilots be permitted to smoke in the cockpit? Oops, left the oxygen mask going...

    2. J. Frank Parnell

      Boeing got dinged for charging several hundred dollars for the rubber feet on a stool used by one of the crew on the B-52. I am sure what happened is the Air Force ordered some replacement rubber feet, the Boeing engineer went to his boss and said, "these things are no longer available, it would cost us hundreds of dollars to make new ones". To which his boss replied: "just give them a bid showing what it would cost us, they will look at it and find someone else to make their rubber feet." Except the Air Force outsmarted them and ordered the rubber feet anyway.

  11. martinmc

    Can't wait until Trump gets rid of all those pesky FAA regulations and the airlines can just go to Lowe's when they need a new bolt.

      1. kaleberg

        We'll see if Boeing can finish trashing its reputation and take advantage of Trump's claim that he is going to eliminate regulations.

  12. NotCynicalEnough

    I'd happily spend a lot of extra money for "mil spec" zippers on clothing as in the race to the bottom, making zippers that last as long as the cloth they are attached to seems to be a lost art. It seems like it no longer matters how much you spend for "quality" clothing, the zippers are all crap.

    1. Salamander

      I'd disagree with you on zipper quality, but a quick look at my wardrobe reveals that all my clothing with zippers seems to be at least 20 years old. I've got a winter coat that i've worn since 1977! Sears!

    2. nikos redux

      Check out Alpha Industries, they sell mil spec jackets. The company's origins are as a 1960s DOD contractor for bomber and field jackets.

      Not cheap, but you said you're willing to pay.

  13. TheMelancholyDonkey

    Military hardware is engineered within an inch of its life. The tolerances required are far tighter than those of machinery you buy at Home Depot. Occasionally, one of these stories actually does highlight some real price gouging. Most of the time, though, the parts cost a lot more than what you would buy at the hardware store because the manufacturing and quality control processes are a lot more rigorous than anything you would ever buy.

    We can have a debate as to whether it was a good idea to go down this road rather than making and using less expensive equipment. But that's water under the bridge at this point. And going with that less expensive equipment will lead to higher casualties, and higher manpower pools.

    1. lawnorder

      There are places (not aircraft) where milspec drives the cost up enough that the result is substantially fewer of whatever it is. For example, which would you rather have; a thousand Stingers of which one can be expected to malfunction, or for the same price two thousand Stingers of which four can be expected to malfunction? Milspec gets you fewer but more reliable munitions, which is not always the smart way to go.

      1. TheMelancholyDonkey

        The problem is that, when military equipment fails, someone dies. (I mean, your guy dies and not the other guy.) Aside from saying something about how much you value your guys, that also necessitates having more guys to replace them. The switch the US made to an all-volunteer force in the 1970s inherently meant that the guys were more valuable, and the tolerance for failure went down.

        The classic example of this was the German/Soviet war of 1941-45. The two forces had diametrically opposed philosophies on this. The Soviets built cheap equipment that failed often*. The Germans destroyed it in huge numbers, but the Soviets had the manpower and industrial base to keep pumping them out.

        The Germans, on the other hand, were manpower poor. They never managed to replace he losses they suffered over Barbarossa and the first Red Army counteroffensive, let along those at Stalingrad. They couldn't absorb the kind of losses their enemies could. In response, they produced very high quality equipment with a focus on protecting crews. They had to, to minimize casualties.

        So, yes, there is always a trade off made in this decision, but the decision to go with fewer units of more expensive hardware is pretty complicated.
        *The idea that the T-34 was ruggedly reliable is a myth. When it was working, it was a fine tank (though not all the way to its reputation), but it broke down at ungodly rates. It got the reputation for being reliable for three reasons. The first is that they were able to produce it in enormous numbers, so it seemed to the Germans (who, for reasons, were able to set the historiography of the war and create conventional wisdom) that it had to be reliable, because they couldn't fathom the Red Army's actual manufacturing capacity. It was fairly easy to repair. And it was a lot more reliable in the Russian winter, because the tolerances in it were so sloppy that there was room for the components to shrink and expand with the weather.

    2. kaleberg

      Check out "Race Against Time" on archive.org. It's a WW2 propaganda film where some poor bullet inspector takes a bathroom break and winds up killing a US infantryman in the Pacific somewhere. A guilt trip like that might convince someone to hold it in until the end of the shift.

  14. Chip Daniels

    I have noticed a pattern among all the "Ermagerd the Gubmit spent 600 dollars on a hammer/ toilet seat/ underwater basketweaving class!!1!" stuff.

    Its a documented fact that billions are lost every year to military contractors due to outright fraud. They've admitted this many times, its not in dispute.

    And yet...oddly, these sorts of stories never seem to make Grandpa's fwd;fwd;fwd;fwd emails.

    I'm done, and I mean really done listening to anyone braying on about government wastenfraud.

    Anyone who starts banging that drum is a liar. Not mistaken, not in error, but just f*cking lying their ass off.

    Because if the Bush/ Trump years have shown us anything, they don't give a rip about any of it. I won't debate them about it, because I don't accept the terms of the discussion. I would just as soon argue with a creationist about the age of the earth.

  15. realrobmac

    No one who works in the aircraft industry, especially anywhere close to parts and maintenance, would be surprised by any of this. Every single aircraft part needs paperwork and without the proper paperwork, the part is useless. This shit is complicated, people.

    1. kaleberg

      If you visit a hardware store near an airport, you'll notice that they sell left handed and right handed metal shears. I remember wondering how many left handed metal works were in a typical aviation repair shop. Then I looked closed. The left and right refer to which is the upper or lower blade. It apparently makes a difference, so shears are bought in pairs.

      1. TheMelancholyDonkey

        Lefty here. Which is the upper blade is (or, as I'll get to, should be) the distinction between all left vs right handed scissors or shear. The blade orientation of standard scissors make it so that, when they are used by right-handed people, the blades are pushed together when they are closed, while using them with your left hand pushes them apart. The latter dramatically reduces the utility of the scissors. With left-handed scissors, it's the other way around.

        Unfortunately, it's become very hard to find true left-handed scissors to buy. These days, it generally just means that the handles are shaped to be used with the left hand, but they still have the blade orientation of right-handed scissors. It's very frustrating.

  16. Salamander

    We pay something like $177 million ($177,000,000) for one F-35 fighter jet, then whine because one of its bolts costs $45.? Or $600, or whatever? Okay...

  17. steverinoCT

    I was a submariner. Going from a 1960s-vintage sub to a newer 688 (which is now over 27 years old!!!), a lot of equipment was more-or-less off the shelf commercial, placed on sound and shock dampening mounts rather than being designed and built to be sound and shock resistant themselves. Saves a lot. Also, famously, the newest Virginia class subs have fiber-optic electronic periscopes. The designed control for that was a special $30K joystick. A clever lad realized that a $30 videogame console controller would work as well, and if it broke, well, just get another out of stores. Done. And the crew didn't need any training to use it.

  18. name99

    You leave out the minor detail that the reply was ALSO on Twitter....
    And at least in my Twitter stream the two arrived together - claim and counterclaim.

    This is the issue.
    The right has stupid people, yes, but they mostly have no power.
    The left has people who want to limit all alternative voices, and they have plenty of power.
    X/Twitter is valuable precisely because it still runs on old-school liberalism, allowing multiple voices, with explanations and answers generally coming through after a day or two as knowledgeable people see an issue and respond.
    You don't get this on traditional media -- only the voices chosen to respond do so. And you don't get it on Bluesky, which is already turning into a parody of a 24/7 Struggle Session run by HR.

    1. kaleberg

      It's more the other way around. The folks on the left haven't a clue about power. To be more accurate, the folks on the left have social power but the folks on the right have economic power, and when it comes down to it, economic power is the power that matters.

    2. realrobmac

      Don't know if you have been keeping up with current events, but the stupid people on the right currently have ALL the power.

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