The first step in building a metal box is to notch the corners.
To kick off Metallic Moments, our series on metal working and fabricating, let’s take a look at one of the basic techniques in metal work – making square corners. Jim Koper is a master metal worker at Storm Copper and he has a passion for custom work that lets him exercise his creative nature.
“The first step to making a metal box is notching out the corners so they’ll meet at the right angle when you bend them together. While you can bend sheet metal up to 16 gauge by hand, using a piece of wood and a mallet, it is a very difficult and tedious process. And for 18 gauge you’d really have to struggle with it. So, once I’ve notched all four corners, I’ll be using a box and pan handbrake to bend the sides,” he said.
Koper went on to explain that a sheet metal handbrake bends sheet metal by using a hinged clamping bar to hold the metal down against the bed. A hinged bending “leaf” is lifted to fold the metal around the fulcrum point of the clamping bar to the desired angle. However, with a standard hand brake can only bend three sides. A box and pan brake is designed to prevent the metal from hitting against the clamping bar when the 3rd and 4th sides are being bent. The clamping bar on a box and pan handbrake is divided up into many assemblies called “fingers” which can be removed at each end of the box.
Once the corners are formed, Koper uses a TIG welder to seal the two pieces of each corner together, and then he grinds away the excess bead to dress up the seam and make the corners into a smooth joint. Tungsten inert gas (TIG) welding, is an arc welding process that uses a nonconsumable tungsten electrode to weld two pieces of metal together. During the bonding process, the area to be welded is protected from atmospheric contamination by a shielding gas and a filler metal is normally used. The shielding gas is usually an inert gas such as argon.
“The twisted handles I put on top are made from ¼” square stock that has been heated to 1200 degrees to anneal or soften the copper. Then once it cools, I put one end in a vice and use an adjustable wrench to twist it, and then make the curve by bending it over a piece of pipe,” he added.
The next step is to pickle the whole box in muriatic acid to remove the scale that develops from welding, and then it’s just hand polishing to develop the final finish. While admiring his work, Koper offers a bit of encouragement to those who would like to duplicate this box. “Boxes aren’t that difficult to make, just basic hand work.”
This beautiful copper box was fabricated using .024 gauge decorative copper sheet. Contact our friendly customers service staff at 1-888-334-2177, or order online at quickshipmetals.com.
