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This is the third installment of Hands On, a series of informal posts dedicated to honoring the people, machines, and processes involved in making and manufacturing.


Until now, Hands On has focused on larger manufacturing in the traditional sense-- but we also want to shed light on the craft movement and makers who, in essence, are manufacturing a product completely by hand, item by item. So today we take things in a different direction as we meet Carson Sio, owner and sole employee of Sio Metalworks.

Sio Metalworks is not the first of our featured makers to be based in the Kensington section of Philadelphia, and it’s easy to see why; rent is dirt-cheap in this once heavily industrial neighborhood, which gives artisans like Carson plenty of space to develop their crafts.

Sio Metalworks lives in a huge warehouse, a space filled with shop machinery of every kind, stacks of wood and metal and other raw materials, and piles other things that I wasn’t sure if were trash or the beginnings of someone’s new project. In short, a playground for all sorts of manufacturers, builders, artists, and makers.

Carson has been working with metal for 2 or 3 years, a skill that he has picked up on his own since completing his degree in industrial design at the University of the Arts here in Philadelphia. Living just a short bike ride away, Carson spends his weekends and 2-3 nights a week here fulfilling commissions and learning more about his craft. Carson enjoys the “zen” of handwork, which is easy to understand. Observing his patient focus on the repetitive strike of the hammer feels like a kind of meditation. I can see what he likes about it.

The ever-expanding product line of Sio Metalworks includes tea kettles, light fixtures, bracelets, silverware, mugs and cups.

Today, Carson walked us through the process of making on of his copper mugs-- a beautiful piece that he typically sells for $125. At that price, it's a steal when you consider the care, time,  and attention that goes into each one.


In metalworking, there are two tools that are fundamental: the hammer and the stake. The stake-- the steel base on which the material is place, and the hammer, the piece of steel that strikes it to shape it. To a large extent, that's it! There are other tools of course, but nearly everything can be reduced to one of these two essentials.

I was surprised by the informality of Carson's relationship with his tools. More than once I asked him about the specific name of some tool, only to be answered with, "Well . . . it's just a hammer." Metalworking, I learned, is far from academic. Sure, there are different stakes and hammers for different purposes, but there's also a wonderful practicality to it. It's not so much about doing it the "right" way; it's really more about hitting the right piece of metal with the right shaped tool, wherever you can find it.

Carson's workshop is filled with hammers, stakes, and anvils of all sizes, all polished to a mirror-smooth finish to avoid marring the working material. His collection, he tells me, was assembled a little at a time from Craigslist and flea markets, along with a few he made himself. One of his stakes was once a piece of train rail; another is the polished and repurposed head of a sledgehammer.

Speaking of this pragmatic approach, Carson notes: "To a metalworker, all the world is a stake or a hammer."

There are other tools as well: an acetylene torch, buckets of chemical solutions for treating and cleaning, measuring tools, and perhaps most importantly, a stack of books. Since Carson is self-taught, in a way these books are the foundation of Sio Metalworks. And they are pretty old. Metalworking, Carson reminds me, has been around for a long, long time, and the methods haven't changed much. These techniques don't go out of style.


For this piece, Carson is working with copper. All metals have slightly different properties, but not as different as you might assume. The main difference is hardness, and on that spectrum copper falls on the softer end. It's relatively easy to bend with the bare hand, but even copper is harder than precious metals like silver or gold. Sio Metalworks works in silver as well as copper, but copper is typically too expensive to use unless it's for a commissioned project.

Working in silver all the time would be ideal, but copper is what's in the budget. No matter though, since they're similar. Essentially, Carson is applying silversmithing techniques to copper, which is what he's showing us today.


This mug starts out as a 8" diameter circle of 20-gauge copper sheet. The first step is to "crimp" the metal to give it a "bias." In metalworking, like when sketching a line, the idea is to start with a rough outline and then gradually refine. You can see this process in the above video.

Crimping is done on a concave stake to form the metal a gentle, wavy cone shape.

The next step is to begin raising, or forming the shape of the mug. With the piece once again perched on top of a stake, Carson works the metal by hammering at the base and working up toward the rim in concentric circles. The idea is to "raise" the sides of the mug up at a very slight uniform angle, about 20 degrees. This angle is slight enough to prevent cracking or wrinkling of the metal.


After raising the metal at a small angle, the mug looks like a Frisbee and it's time to anneal it. All that hammering causes the copper to become "work hardened," and it becomes tough and brittle. "Annealing" softens it up for further working. Carson heats the disc to 1100 degrees F with an acetylene torch. We visited in the afternoon, but if it were dark, Carson says, the copper would have a cherry glow. 

After heating, the disc sizzles as it is tossed into a bucket of water to cool, and then rinsed in another bucket of acid to remove the black oxides which have formed on the surface. Carson invites me to feel how soft it's become, and he's right. I accidentally bend it out of shape, but he assures us that it will be worked out in the next step.

Actually, the next step is raising again, but this time at a sharper angle. This particular mug will take 4-6 repetitions, or "courses" of raising the edges and then annealing before this part is complete.


Once the copper has been raised to the point that it actually forms a cup, it's time to finish the surface. This is done by a process called "planishing," in which the metalsmith uses a flat, polished hammer to cover the surface with hundreds of tiny dings. The effect is vaguely like disco-ball, or a cut diamond.

The surface could even be refined further with a lighter hammer, as in the pic to the right-- Carson would smooth out all the little ridges to give it a highly reflective and uniform surface, like in the the case of silverware.


Finally, with the body of the mug complete, the edge is rolled back to give it a rim, making it easier to drink from and hiding the unevenness of the metal.


Almost done! The last step is to forge the handle out of a piece of think copper wire. This is by far the loudest and most violent step. Carson raises the hammer past his shoulder and takes full swings to flatten the wire, and I suddenly understand why he has a box of earplugs on his workbench. 

He then uses a hacksaw to split the end into a Y and continues shaping, and then welds or, in this case, rivets the handle to the piece.


For the final touch, Carson soaks the piece in a chemical solution of "Liver of Sulfur," which smells as bad as it sounds. This chemical creates a patina on the surface which is polished away in the high areas but left untouched in the low spots, leaving a gorgeous antiquated look. Next a wax sealant is applied for shine and to protect the patina, and that's it.


Thanks for having us, Carson!

For more about Sio Metalworks, including process pics, commissions, and contact info, visit siometalworks.blogspot.com.

Or shop at Sio Metalworks on Etsy.


Hands On Manufacturing Series

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