Which is why they need to get their first paid job so they can prove it. They can make lots of bold claims for their own tunnel, but if they prove it's true on a real job, then their technology suddenly becomes much more valuable.

That said, I'm skeptical too.

He set up a line between Washington and Baltimore, and transmitted the news from a convention in Baltimore. It arrived in Washington 64 minutes before the train bearing the news did, thus proving it worked.

Within 2 years, there was 2,000 miles strung, within 4 years, 12,000 miles. People had discovered they could make money by using the telegraph. People who received news faster made money.

In March 1843, the US Congress appropriated $30,000 to Samuel Morse to lay a telegraph line from Washington, D.C. to Baltimore, Maryland, along the right-of-way of the Baltimore and Ohio Railroad.

$30K in 1843 was around $1M in today's money. I wonder if that $30K paid for the whole project or if Morse had to kick in some of his own.

Without environmental and employee protection laws, or permitting concerns, maybe it would be doable for under $1M today. Since copper is so expensive, I thought the cost of wire would dominate the expenses, but 5000 ft of uninsulated 16 gauge wire sells for $400 on ebay, so 45 miles worth of a pair of wires would cost around $40K

Shouldn't the boring company prove that it works before they get offered the job?

Don't think this is paid.

My understanding is that the way he gets most of the way to 10x is to dramatically decrease tunnel size and to have the machine dig and create the tunnel simultaneously. The second part may be valuable to other tunnel boring companies, but most municipal projects tend to use quite large tunnels, where Musk's machines wouldn't be a viable solution.

And now that you mention it, this is going to be the other major issue with the boring company - unions, people and regulations.

We probably need unions to help stop wage stagnation. Which is why it sucks that unions in the US are so terrible.

That tells me all I need to know about why The Boring Company exists.

EDIT: Theptip below found the URL I could not, for boring machines that assemble the tunnel while operating: https://www.herrenknecht.com/en/products/core-products/tunne...

The standard with US subway construction today is massive tunnels with huge, expensive stations. Seems to be a design choice from Musk.

That said, I don't have any particular insight into the field itself; however I do have a respect for Musk's ability to rephrase the problem just slightly (e.g. landing boosters to save costs) and to turn the whole economics of the situation on its head.

How? These pods take 16 people, and per the article, only one can set off every 30 seconds. This limits capacity to 2k people per hour (even assuming that it manages the promised numbers, and historically Musk stuff doesn't), which is far less than one would expect of a decent bus rapid transport line, never mind an underground train.

Parallelzation applied to subways.

Single big trains get delayed due to any number of reasons - something on the tracks, broke-down train, etc...

With 10 smaller tunnels, they can just be rerouted.

Generally, every city has big transportation hubs - airports, train stations and so on - located at strategic places within the city. Musk's idea is to ditch these hubs and replace them with more frequent and much smaller stations which get you closer to your destination. On the other side if they don't have to move millions of people to the same hub but rather move a much smaller number of people, they can afford to dig smaller tunnels and stations which are way more easy and fast to build.

For instance, in London every time they build a new transportation hub, it takes years. These stations are massive, they literally dig in every direction for several meters.

I don't know if it's going to work but surely there's thinking behind it.

Edit: typo

This also could really only be the long time play anyways - it's the only reason using autonomous battery powered model X's as the "cars" makes much sense.

I think it's an interesting idea, Musk obviously likes his sci-fi. He is basically attempting to implement packet switching for human mass transport vs. the current circuit switching we have.

The actual cost of tunneling itself is generally fairly cheap--somewhere around $50 million / mile. The expensive part is the stations. You can probably save money without having to build mezzanines, but the lower utilization of the tunnel and the greater number of vertical access shafts needed (not to mention the challenges inherent in moving through that very crowded portion of real estate) is probably going to cause cost blowouts compared to subways. Particularly if you design the tunnels to move cars, not people (SOV cars being about the worst use of space possible).

If you have 4x as many trains but don't load and unload on the same platform you could easily get by with 1/4th as many passengers per train.

The factors that limit train frequency are station dwell times and switching time. A subway line can generally hit 26TPH, and the top speed of most subways is usually about 70mph, with average speeds generally being in the realm of 30mph. Making trains faster actually reduces capacity; a HSR that goes 220mph is considered to have a capacity of around 4-6TPH. You can also improve throughput by cutting out all branching; Moscow gets about 40TPH as a result, which is about the feasible limit of rail systems.

30 MPH which is low = 5280 * 30 = 158,400 feet per hour / 26 TPH = 6092 feet per train. Actual subway trains are 600 feet or less long ~= 10% utilization. At 30MPH cars don't keep 126 feet between each other. Bump that to 60MPH and the trains are at 5% or less utilization and again cars don't keep 266 feet between each other even if they should. And again this is very long 600 feet subway trains most are significantly shorter than that.

Further trains have a stopping distance @ 62MPH of 820 ft with (0.15 g) deceleration. High speed trains can get an extra 0.3 m/s2 deceleration which could also be added to normal subway trains but would be an emergency situation as they knock people over.

PS: At 60MPH the theoretical limit is over 220 trains per hour assuming all trains can stop before hitting the train in front of them. But you can only approach that with full automation and multiple lines for acceleration.

We can also exclude any car stopped at a station, as you can have multiple cars unloading at the same station or have a train bypass a station without making a wider tunnel.

Sure, but we're talking about subway networks underneath major metropolises, and adding extra tunnels and platforms is basically as expensive as digging a whole new line - when it is even possible due to space or geological constraints.

Building a new network would not be constrained by existing implementations. For example, you can't just drive the trains faster on existing systems. Everything would have to be redesigned/upgraded to do it - the motors, tracks, track bed, brakes, suspension, safety equipment, schedules, signals, everything.

That doesn't answer the question. Why would the transport be "correspondingly faster" in a smaller tunnel than a bigger one, given both are new digs?

If the units/hour capacity can be met with a smaller tunnel running fast little pods on a single track, then boring out a larger tunnel that could fit perhaps three tracks would be redundant.

And that assumes that the pods could run on adjacent open tracks like railcars, whereas the intended design may require a smaller tunnel bore that is close to the size of each pod.

Likewise with the Boring Company. Of course they still need to prove themselves, but the factors that work in their favour in tunnel construction are the same ones that favoured SpaceX.

ULA and the established rocket manufacturers made big profits off the fact that launching rockets is stupidly expensive. That meant their profit margins ended up being stupidly large quantities of money. Musk’s contention on big tunnelling projects is that big construction companies have similar incentives not to reduce the costs of tunnelling. However Musk as an outsider is free to innovate and develop the engineering and technology because he doesn’t have big fat profits he’s already tied to.

All these features already exists in current and older machines. And the rocket market is different from the boring market.

Actually its not. TBMs are crazy expensive as of now. Any major disruption in price will be a total game changer for public transit systems.

Has the reused items proven reliable and profitable in he long run, which was the only reason others were not doing the same...

They claimed what was technically impossible?

Do you have a citation for that?

These things have existed for a century now. The fact that no one tried and it took a person with money from early dot com start up exit means others goofed up enormously.

Anybody could have tried. They didn't. Pulling down other peoples achievements because one didn't try the obvious themselves already reeks of envy.

[1] I have heard that the machine supported a reverse gear but Seattle elected not to include its use in the contract because it added a few million in cost. :/ I don’t know if this is actually true though.

For too long that part has been fiefdom of big earth mover companies.

It's equivalent to measuring software developer productivity in lines of code.

Also, as a sibling comment mentions, the 10x claim is pretty disingenuous in the first place.

Has Elon's company figured that problem out?

Antithenes is referring to this classic Clarke and Dawe bit: https://youtu.be/3m5qxZm_JqM

Anticipated. And this is probably top speed in perfect London clay, not average speed in average conditions.

EDIT: Oh, and it's also by reducing the size of the tunnel by 4?

E.g. https://www.quora.com/Why-does-Elon-Musk-think-he-can-bore-5...

A large part of the "10x faster" claim is from a 4x speedup from drilling a 4x smaller hole. That's not a boring machine improvement, anyone could drill such a hole with an existing machine. (I've heard the claim "10x cheaper" too). If you make a smaller tunnel with lower throughput than a subway, then you need more of them, so it's not clear to me that you can claim a speed improvement just because you can do one of your tunnels faster. Indeed if you more than halve the throughput by halving the tunnel cross-sectional area, and halving the boring time, then you've made the whole system more time consuming to create.

Another claim is that current tunnel boring machines (TBMs) stop for 50% of the time, to allow the supports to be put in; this will give them another 2x speedup. However a cursory Google search (I'm not an expert in this field) shows that the technology for continuous TBMs already exists [1]. That reference contains a very in-depth video if you want to see exactly how these things work, it's very cool. This machine can apparently do 2.8-12.5m diameter holes, which covers the diameter that TBC is targeting. (As I've fact-checked this point further, the Boring Company's website makes the more restricted claim [2] that "current soft-soil machines tunnel for 50% of the time"; maybe the overly broad claim came from misquotes in the press and not from TBC themselves. I haven't found any soft-soil continuous TBMs yet).

Finally Musk claims that current TBMs are operating well below the thermodynamic maximum, and so he can get another 3x speed boost. On this point I'm not qualified to debate; it seems unlikely that there's that much gain left on the table (surely the TBM companies that currently exist have spent a lot of money plucking the low-hanging fruit of efficiency gains?) but Musk has sent rockets into space so perhaps he knows what he's talking about here.

[1]: https://www.herrenknecht.com/en/products/core-products/tunne... [2]: https://www.boringcompany.com/faq/

What we need is more people like Elon. It's not magic, many others can do what he does, though few do (maybe because of social pressure? Look at all the crap Elon gets). There's a lot you can do just by having energy and willingness to try things and being unsatisfied with the crappy status quo.