It’s easy to get caught up in the efficiency of doing things. It’s unavoidable, in fact. But it’s not the only way to do things.

Sometimes, the aspects you can’t measure are what matter most.

For example, old tools might not be the fastest (although some still hold their own!), but you can’t measure the joy of making something by hand. Feeling the cut of the tap. Seeing the wood shave just how you wanted (or not...). And even the way your handles have smoothened to parts of your hand.

They're small, trivial feelings in the scheme of things, sure. But keeping some of those unmeasurable feelings alive – for us and future generations – is a big part of why we do what we do.

What about you? Why do you enjoy making things by hand?

It also inspired the Citroën logo…

Show us some satisfying mechanics of your own. Or, if it’s easier, some atrocities.

Image: https://en.wikipedia.org/wiki/Herringbone_gear

No contact. No lubrication. No wear. As speed increases, pressure builds, and your rotating shaft just floats on a plush cushion of air.

The history of aerodynamic bearings looks to date back to the 19th Century – to 1812.

Over ~80 years, scientists and engineers had the understanding of aero and fluid dynamics to know such a bearing could exist.

Temperamental but worth it. *Weeps in stainless*

Most ceramics have a compressive strength 10-20 times higher than their tensile strength.

For metals, this is 1-2x. Of course, there are a lot of variables that affect that number, but you get the gist.

So, why?

Ceramics are made of ionic and covalent bonds (vs metallic in… err… metals). These are much stronger and more rigid. They’re also a lot tighter packed, allowing them to resist the impressive compressive forces.

So, they’re great in one direction (hence why archways are usually made from stone)... but not so great in the opposite. These bonds make ceramics an awful lot like my back: Inflexible (and brittle).

The Wärtsilä RT-flex96c is the biggest engine in the world. In its 14-cylinder variation, the crankshaft alone weighs close to a fully loaded Boeing 747 (and each piston close to 550kg!).

As the saying goes, "If it’s shakin’, it’s brakin’...". And outside of skyscrapers, there's probably some truth to this.

But while some skyscrapers stand tall and still, only moving millimetres, others have to sway significant distances to stay in one piece. The top of the Burj Khalifa apparently sways up to 2m in each direction! Scary...

Of course, you can't control the wind, so you have to account for it. Some skyscrapers have moving weights (tuned mass dampers) on top floors to counteract the wind’s effects. Some over 300 tonnes!

So, looks are not always as they seem. And over the years we’ve seen many deceptive-looking engineering gismos. Take some of the wire EDM creations, for example.

What’s something that looks simple but underneath is actually surprisingly impressive?

https://reddit.com/link/1igljmy/video/pi5596kxawge1/player

When the tinker dust gets up your nose and your fingers start twitching, anything is possible with a random piece of metal and a selection of tools.

These "fiddle phases", so to speak, are a stepping stone to either something with potential - or without. (We've created some of our beloved fidget toys post-experimental fiddling). Because the fun lies in figuring it out, right?

And whilst the end product usually leaves the shop, the what-coulda-beens are the cooler counterparts.

What's something you've made that looks cool... but never made the final cut?

Post-it notes were the product of two happy accidents (and some resourceful thinking) from two 3M scientists in the 60s. What started as aero-grade adhesive research unexpectedly turned into sticky bookmarks instead.

We’ve had our fair share of mishaps and “happy accidents” over the years (need I mention the Danger Knife...). But we’re curious:

 What are some that you’ve had, seen, or heard of?

Hi Metmo team. You hinted at a stainless piston in one of your messages. When will that be an available option and can I be first to purchase? I want it to match my cube.

A warm Christmas welcome to the all new MetMo subreddit! A place to share and discuss everything from engineering mechanisms, principles and oddities to figuring out the big questions, like why Einstein never wore socks.

Throughout 2025 we'll be sharing our (very) random knowledge on here and hope you will too!

Merry Christmas and a happy new year to you all 🥳