HMS Metals

Heather Schramm

Design and Fabrication: Copper Cup - Part One

ProcessHeather Schramm

Hello everyone and welcome back to my blog. I’ve decided to base this months post on a Copper Cup Workshop I took at the Baltimore Jewelry Center with David Harper Clemons at the beginning of February. I took this workshop to both get comfortable with new techniques and because I would like to offer tableware on my site store later this year. I may also be a sucker for Moscow Mules!

During this two day workshop we were taught how to fabricate a Colonial Style Beaker using either a butt or lap joint to begin the fabrication process. To break these two joints down into laymen terms, a butt joint is a joint formed by two surfaces abutting at right angles. While a lap joint is made with two pieces of metal by halving the thickness of each member at the joint and fitting them together. I’ve utilized the butt joint many times. Therefore, I chose to create my cup using the lap joint because this particular joint gives you the strength needed for forming the piece later in the process.

Now for the fun part. Process and Fabrication! I started off with a 6x12 inch sheet of 16 Gauge Copper. This is what my template was cut from using my Knew Concepts Jewelers Saw. After my template was cut out, I filed my edges smooth and used a ruler to add an additional tab to the opposite side of the template.

After all my edges were smoothed out and I cut the tabs into my template. I used a Raw Hide to bend both sides of my template in opposite directions. This gives me the space and angle I need to file down each tab so it resembles wedge. Once my tabs are wedge shaped, my acetylene torch accompanied by flux and solder will be used to sweat solder the tabs on my template. During this process my metal became softened (annealed) due to the heating process. Quick side note: when properly annealed you can bend metal by hand using little effort. This allowed me to get my template roughly into shape before I added more flux to the tabs and used a stake to flatten the surface with the seam out. It is important that the metal fits snuggly together that way when it is reheated to solder that joint it doesn’t move or create any gaps within the seam.

Once the seam fit together, I returned to the soldering station and applied additional flux and solder to the seam this ensures the seam will be complete. After soldering, the piece is then put into pickle (an acid bath) and neutralized before I can do anything else with it. Once the piece is completely dried off I brought it over to a flat stake and began to hammer around the seam to ensure the thickness of the piece is consistent. After this the piece is brought back to the torch and annealed before being rounded out on the Blow Horn Stake to round it out.

Once the piece is rounded out and I have double checked that all the seams are still intact. I can start leveling out my piece this means, removing any metal that may have stretched outwards during the initial shaping process. Once both the top and bottom have been cut and sanded level. I can clean up any extra solder around the seam using a flex shaft and begin sanding the form. After a quick round of sanding, I brought the piece back to the Blow Horn Stake in order to begin planishing (adding texture).