Boeing Everett This is the largest enclosed manufacturing space in the world by volume, it has its own internal weather system and micro climates inside the building. It’s about 13m cubic meters. It was built in 1967 to build the 747 jumbo jet. What is interesting is that Everett operates as an assembly line, that is continually move in the same way a Ford autoplant does. Before 67, jets were assembled in batches where the aircraft would sit stationary in assembly bays and several would be built side by side in a batch. The SR-71 was built in stationary batches. The two production types warrant different quality systems, different tooling and capex requirements. But the MAIN issue between these two types of manufacturing method is the cycle time of each assembly step at each station. In batch production, each assembly step can be different duration. Step 35 might take 45 minutes, step 235 might take 11 minutes and step 6235 might take 5 hours. This works because every aircraft in the batch does each step concurrently, in parallel. In continuous assembly line production, all the steps have to be the same cycle time duration. Otherwise the entire plant moves at the cadence of the slowest station and your utilisation collapses. This is why continuous production is so hard, you have to design for piecewise assembly, and if you do not start with piecewise assembly as a starting design philosophy you’re going to have a very bad time. Being able to design for parallel and serial assembly is a super power. Product designers too often focus on performance and too rarely do they focus on how the product is built until it’s almost time to build it. Anyway, Everett exists, so doing things at 1,000 acre scale is perfectly doable.

The Scissor Test. Within the first few weeks of me joining TBC, Steve gave me the direction that he wanted to be able to walk around a Prufrock with a pair of scissors, be able to cut any wire, and the machine should still be able to mine. Obviously this was a hypothetical exercise, but the goal was real. What followed was a deep system-wide failure mode effects analysis and a complete redesign of the machine’s electrical system to be able to pass the scissor test. There are still a few single points of failure where the complexity or cost tradeoff doesn’t make sense to design out, but for the most part Prufrock now passes the scissor test. Being robust to a single failure is obviously important, but equally as important is observability of those failures. Without observability, a failure can lay latent in the system without anyone noticing for years and then when the backup fails the system will still go down. For this reason we make sure to instrument each redundant connection so when any failure happens we instantly know, get a notification, and can schedule a repair for the next maintenance day - all while Prufrock keeps mining. That’s what lets these machines keep mining continuously with zero people in the tunnel. We’re hiring electrical engineers. Come help us keep pushing this further. Link to apply in the comments below 👇

If you’re inside Prufrock while it’s mining, you never really see dirt. The only dirt is on the conveyor over your head. In front of you: the stationary shell (pictured below). Behind you: a finished tunnel. There’s a watertight seal between the inside of the TBM and the outside world. Without it, tunneling under the water table wouldn’t be possible.

This is Prufrock, riding The Monster, riding an SPMT, driving through Las Vegas. After we retrieve a machine, an SPMT drives directly under The Monster. That lets us move this 530,000 lb Prufrock section plus the ~140k lb Monster through city streets. The SPMT is a self-propelled modular transporter: dozens of independently steered axles that can crawl, crab, and rotate a load this size around an intersection. When we get to the next site, The Monster tilts ±10° and launches Prufrock straight into the ground.

Each Prufrock carries 2.6 million watts of electrical capacity. That’s the same as: • ~4,000 corded power drills • The continuous draw of more than 2,100 American homes • 1,444 hair dryers running at full blast We typically only use about half of that at current mining speeds. The rest is pure headroom for going faster. Three 13.2 kV substations power every machine. All three designed in-house by our electrical engineering team. We’re hiring at every level. Link to apply in the comments below 👇

I’ve never seen a real inventory system succeed without physical access control. Has anyone actually pulled this off—even at the small, sub-team supply level? Not talking Kanban for consumables. I mean actual inventory. If so, what was the trick?

On hard-rock machines like Prufrock Main beam, the propulsion system doesn’t push off a tunnel liner — because there is no liner. The rock itself forms the walls. Instead, Prufrock Main beams grip the tunnel walls with ~4 million pounds of horizontal force. Think of bracing yourself hard against both sides of a narrow hallway and then pushing forward. That’s the principle. By gripping the rock directly, we delete entire subsystems: no liners, no erectors, no segment handling, no grout. The result is counter-intuitive: the maximum theoretical tunneling speed through hard rock is significantly higher than through soft soil. Simpler machine. Faster progress

Everything takes longer than you think it will — no matter how hard or how fast you work. And while you’re in it, it almost always feels messy. That perceived "mess" is usually a sign you’re actually growing. The only organizations that feel clean and orderly all the time are the ones that have stopped evolving. Static. Bureaucratic. Safe. When you’re in the middle of it, it’s easy to look at the chaos and decide something is broken. Most of the time it’s the opposite. Growth requires change, and change never shows up neatly packaged. Part of my job is helping the team — and myself — hold this perspective.

🔥 PART 4 | FIRST EVER RECORDED Boring Company Full Tour Steve Davis (President of The Boring Company) sits down and goes deep on tunnels, Prufrock, Bastrop Tunnels & more. @boringcompany @Mike__Baier In this exclusive Part 4, Steve Davis spends real time talking with me about everything happening behind the scenes at The Boring Company — from the latest tunnel progress to what they’re building next. This is the most in-depth, unfiltered conversation ever captured on camera with Steve Davis about The Boring Company.