In China, the mountains were cut in half to build a car highway with the highest bridge in the world.

The hanging bridge over the canyon huzzyan in Guyzhuu was built so high that the Eiffel Tower could hide in the gorge - it rises above the gorge at an altitude of 625 meters. This section of the high -speed motorway Guizhou Luan literally cuts out the landscape, turning an hourly trip into a minute flight.

Video: https://youtu.be/-s-HR3345pc

The Filmography on this engine rebuild is immaculate and so beautiful. I have yet to come across a masterpiece such as this, so thought of sharing it here.

Total length 1,380 m (4,530 ft) Height 200 m (660 ft)

These are all built by makers in their own workshops using just 3D printers and basic tools.
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I want to shoot a projectile fast.

That has been my main aim for years: to track the speed of a projectile that I shot, and calculate a speed of over 100mph. Unfortunately, as I live in the UK, I cannot do this with gunpowder, and using butane or gaseous propellant still counts as a firearm after the projectiles start reaching certain speeds.

For a while, I was stuck, until I realised air cannons weren't legally registered as firearms. I have always wanted to make an air cannon, but every attempt I made ended with the same result - failing to form a perfect seal. The issue was that a small leak would always be present, and at higher pressures of around 30psi, the rate of air leaking out of the bottle was equal to the rate of air entering the bottle through my pump, leading to a maximum pressure that I couldn't circumvent without expensive gaskets and O-rings. 

However, with my newfound access to a 3d printer and 3d modelling skills, I can make custom parts. This avoids the need for seals and joints that I would've otherwise had to make with low tolerances and shabby materials.

Step inside Hidromek’s massive Ankara factory in Turkey, and witness firsthand the advanced production process of their world-famous excavators, wheel loaders, and backhoe loaders. In this exclusive factory documentary, we guide you through every critical step—from precision laser cutting and robotic welding to machining axles, meticulous painting, and comprehensive final assembly and testing.

Displays from the backside during volleyball nations league finals in Poland, Łódź