Here is a simple instructable on how to turn a little bit of
mixed sheetmetal into a cool piece of art. For demonstration I choose to make a Sign of the Deathly Hallows wall hanging, but you can apply the same steps to any design you want…
Sheet metal, I used 16oz aluminum and 20 ga aluminum
Pattern making: pen, paper, computer, printer, scissors, tape
Metal cutting: band saw, jig saw, scroll saw, hand shears, throatless shear, knife
Metal working: hammer, anvil, pliers, clamps, power drill, drillpress, drill bits, center punch
Metal finishing: sand paper, palm sander, belt sander, disk sander, files
Final finish: Your favorite patina technique, household oven, oven mitt, paper towels, olive oil
Step 1: Make Your Patterns
First you need to know what design you are going to make. The design has to be simple enough to work out in 2 to 3 “colors” so that you can convert the design into simple metal shapes. Once you know your design, you need to make your patterns. I use GIMP, but you can draw, sketch, or use any other method to make a paper pattern. The important part of the pattern is to have the overall outline of the base and the orientation of each piece on the background (Master pattern). You also need a pattern of each piece to transfer to the metal sheet. All patterns must be at full scale, so if you are printing the patterns on standard paper, they will need to be trimmed and taped to create the final patterns for use.
Step 2: Metal Preperation
Take your patterns and find some sheetmetal they will fit. Use the Master pattern to select your base, and each individual pattern for the components to be added. When working with large sheet, it is easier to cut pieces down to the rough size and shape. As you cut each piece, be sure to check the fit to the Master pattern.
One additional piece you need to make is the wall hanger. I use a small 1” X 1.5” bit of aluminum scrap. I drill a 0.5” hole in one end and soften all of the edges.
Once all of the pieces are cut to shape, use sander/sand paper to soften any sharp edges. You also want to sand the top face to make a clean uniform finish. Now is the time to add any patina to your pieces. For aluminum, I use a commercial product called “Aluminum Black” and for brass and copper I use gun blueing solution. Try to get a uniform finish without leaving any fingerprints. If there are any bad spots, don’t worry too much as you will be removing most of the finish later.
Step 3: Assembly
I use solid round rivets to join sheet metal. Here is how I use them:
Lay the Master Pattern over the base piece of metal. Choose a starting point with 2 of the other pieces. Be sure to start somewhere other than the top most center rivet. You want to save that one for last so you can easily attach the hanger.
With the pattern still in place, drill the first rivet hole. Place a rivet through the hole and align a second set of pieces and drill another rivet hole. Remove the rivet and pieces to separate the Master pattern from the base. Replace the pieces and set the rivets. Use the master pattern on top of the assembly to continue to place pieces correctly. Drill and rivet the pieces in the order that makes the most sense to your design. Again, be sure to save the top most center rivet for last and be sure to remember to attach the wall hanger.
Step 4: Finishing
After all the rivets are set all that is left is the final finish. Using sandpaper or some other fine abrasive, lightly sand away some of the patina. Due to the rivets and over lapping pieces, there will be areas that you cannot get to, but that is alright… It adds character to your piece.
To get a nice glossy finish, we are going to heat the metal and apply an olive oil finish. Heating the metal adds color to the patina and prepares the surface to absorb the oil. After sanding, scrub your piece clean using soap and water. Dry the piece and shake off any excess water. Place it in an oven and turn the oven to 450 degrees Fahrenheit. The oven will need to come to temperature and stand for at least 15 minutes. While it is heating, gather some supplies and clear out a space to work. I place newspaper on a cookie sheet, then add a layer of aluminum foil. Get several paper towels or a small cotton rag and a bottle of olive oil. The metal have to heat long enough to reach 450 Degrees. My 10” circle took about 10 minutes after the oven reached temperature. I could tell by the color change in the copper when it was hot. Brass will change slightly, but aluminum does not show heat. Once you think it is hot, use a pot holder to remove it from the oven and place it on your prepared work area. Using the paper towels, apply a heavy coat of olive oil. The metal should hiss slightly upon the first touch and the metal should change color where you have wiped the oil (well, maybe not the aluminum). Be sure to cover the entire piece. It will still be hot, so be careful. Once it is covered, use a new towel or rag to wipe off any excess oil. Set the piece aside for an hour or so to cool. Once cool, shake any excess oil away and wipe down one more time.
Use a knife edge or small screwdriver to lift the wall hanger away from the base. Your piece is now ready to hang and enjoy.
Step 5: Follow-Up
Even though the photos do not show it well, the olive oil finish does give the metal a deep shine and really enhances the look. I have used this finish on most of my work and these photos show some better pictures on previous pieces.