Comment by exabrial | Hacker News Reader

Comment by exabrial | Hacker News Reader

If you think bricklaying is a simple task, you've probably never laid bricks, or likely ever worked a construction job.

There is _a lot_ that goes into laying a brick wall. From excavation, base compaction, material choice, mortar composition and viscosity, wall type, overlap patterns, leveling, overhang patterns, set time, and much more. Using an incorrect overhang pattern for instance can allow water drops to fall and contact the relatively soft surface of bricks and destroy them in a few years. Having an incomplete mortar seal allows the elements to penetrate through what would normally be waterproof, especially in places with high wind. An improper excavation, compaction material or compaction of said material, improper leveling, and many more factors will lead to failure within just a few years.

The best way to learn about this stuff is to go try it! One could volunteer for Habitat for Humanity or a local shelter that builds homes and get some time with the tools. None of this stuff is simple, straightforward, or easy, and there are a million ways to do it incorrectly.

>If you think bricklaying is a simple task, you've probably never laid bricks, or likely ever worked a construction job.

If you think the bulk of the actual laying of bricks, siding of a wall or shingling of a roof isn't a simple task you've never worked a construction job.

Thinking is required around corners, windows and other interruptions. The bulk of the material laid, hung or otherwise expended is done so in a simple and repetitive manner. Once you've figured out your non-standard bits of the job you basically just run on autopilot.

That said, I agree that 99% of the the engineers who try and design this stuff never actually have the requisite experience to understand the nuance of what's going on.

there's another comment to this effect and it's spot-on. I suspect a lot of the people quick to work on these automation projects don't fully understand the complexity behind it. Just reading the descriptions of the early and later machines shows the comical oversimplification of laying bricks.

A lot of complex tasks are done by machine today, and they do it better than master craftsmen.

The thing is, designing a machine may be really complex, but it only has to be done once. After that, the machine will repeat the process with extreme precision. A machine can position bricks within microns and mix mortar to the milligram, doing things level and with the correct overhang is jokingly easy for a machine.

What machines are not good at is dealing with variation they can't control. Bricks are not perfectly sized, mortar behaves in unpredictable ways, the ground is not flat, not even solid. We humans have no problem with that, and anyone can do a wall shaped construction, but the machine, with its microns and milligrams may fail catastrophically at the smallest bump.

You forgot trees in the yard, how much sunlight the wall receives, moisture content of the soil beneath the brick walls, roots that are growing there, and existing structure.

The hard part isn't laying bricks. It can be already be done in a day efficiently. The hard part is the near infinite things that are different between every construction site.

I feel like bricks were probably shaped the way they are today specifically to help bricklayers do a good job easily and quickly. If we're moving to automated wall building maybe using traditional brick is just a waste of effort. Automation will probably benefit from using different shapes or materials. For example a human can't handle a 30 pound brick but a machine might be a lot faster if you use larger bricks with different mortar configurations.

I've laid a little block and brick for myself. I found it kind of fun and pretty rewarding work. As soon as I saw the headline and started pre-thinking about the content, I immediately thought, "well, the mortar for one thing..." The bricks aren't all that uniform either. My big takeaway from doing myself was that it's easy to obsess over each brick (like a machine might) but when people look at a brick wall, they see the forest, not the trees: it's not necessary for each brick to be laid perfectly.

I also heartily second volunteering for Habitat for Humanity. It's rewarding work, fun if you're with a good crew, and a great way to learn new skills.

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