How Do You Cut a Perfect Circle in Sheet Metal Using Basic Tools?
Trying to cut a perfect circle in a piece of sheet metal? Using basic tools, there are a few different methods that can work. Check out these ideas:
Tin Snips
To create a circle in sheet metal using tin snips, mark the centre of your circle, and punch a hole in the metal in that spot by pounding a screwdriver through the metal using a mallet. Then use a compass to trace the rest of the circle around the centre pointe.
Once the circle is traced, wedge the screwdriver into the centre hole again, ripping it slightly open. This is the space where you are going to wedge your tin snips into the sheet metal. Then, simply cut the metal as you would paper, but with more force, until you have a circle.
Drill
To create a circle in sheet metal using a drill, trace a circle onto the metal as described above. Then, trace a slightly smaller circle inside your main circle. The distance between these two circles should be the size of the drill bit you plan to use.
Once you've made sure your drill bit can handle metal, drill a series of holes in the space between the two circles you have created. This is called chain drillin, and when you have finished drilling holes all around the circle, you should easily be able to push out the inside of the circle. Use a die grinder or a file to smooth the edges.
Right-Angle Drill
Sometimes called a sideways drill, a right angle drill can work well for small circles in sheet metal. Using a screwdriver, rip open a bit of metal where you want the centre of your circle to be. Continue to rip the metal until you have created a large enough hole to fit in your right-angle drill.
Then, wedge the drill into the hole you have created and begin to drill. Your drill bit should be hitting the edge of the sheet metal, and as you move the drill in a circle, it will create a perfect circle as long as you keep the drill steady in the centre spot. Move the drill slowly as it will be difficult for it to cut through the sheet metal, especially if it's relatively thick.
Alternatively, instead of trying to cut a perfect hole in sheet metal on your own, you may want to turn to a professional sheet metal cutting service. They can use plasma, water-based cutting, a CNC machine or other methods to ensure the circle is exactly as you want it.