When Scott at the Melbourne, Victoria-based Wonder World YouTube Channel saw a video clip of explosives that created giant metal spheres, he started looking for more information. What exactly was happening in the video?
That online exploration landed him at a 23-year-old company called Shenzhen Maoping Sculpture Arts, a sculpture manufacturer that handcrafts stainless steel spheres up to 6 meters (20 feet) in diameter. This Wonder World explainer video is a summary of what the YouTuber found via the Joyce Chung Youtube Channel, Maoping’s Sphere-Ball.com, and other online sources.
His conclusions share a step-by-step look how water pressure hydroforming turns sheets of dull metal into a perfect-looking mirror-like sphere.
The video also includes what appears to be the four common ways that hollow metal spheres are created: Spinning, mold pressing, water pressure hydroforming, and explosive hydroforming. From the video notes:
“SPINNING is like working on a lathe, they attach a flat round blank onto a machine, while the blank is spinning at high speed, they use various types of tools to start pressing down the blank into a hemisphere and then weld 2 hemispheres together creating a sphere. This method uses the skills of an artisan to create the hemisphere, and a lot of labour. But Larger companies will use a robot or CNC machine to do the hemisphere forming.”
“MOLD PRESSING is just what it sounds like, they use a big hydraulic press and press a metal blank into mould and form the hemisphere that way, and then weld 2 hemispheres together.”
“WATER PRESSURE HYDROFORMING is when you create a sphere using either flat or slighting curved pieces of metal into a large polygon sphere, and then using a hose and pump to send lots of water into the sphere under high pressure, forcing the sphere into shape. During this process, they can find any holes in the welds they created and seal them up.”
“EXPLOSIVE HYDROFORMING is where you have a large polygon looking sphere made out of curved plates, the sphere is then filled with water and a small explosive charge, and when you set off the charge, the explosive force of the water forces the sphere into shape.”
Watch more about metalsmithing and spheres, including:
• Ball, a collection film by The Mercadantes
• Marbles – The Magic of Making
• Why all world maps are wrong
• The Sphere-Packing Problem
• Hammering, sanding, & polishing aluminium foil into a shiny sphere
• How does artist Anthony Howe fabricate a kinetic wind sculpture?
And previously from Wonder World: Yosemite’s glowing Firefall: Why does it happen?