Quck answer
Cutting sheet metal can be done using various methods and tools. Here are some common ways to cut sheet metal:
1. Tin Snips: These handheld cutting tools are great for straight or curved cuts in thin sheet metal.
2. Electric Shears: Electric-powered shears are efficient for cutting straight lines in thicker sheet metal.
3. Plasma Cutter: This tool uses a high-temperature jet of ionized gas to cut through sheet metal quickly and accurately.
4. Laser Cutter: Laser technology provides precise and clean cuts in sheet metal, but it can be expensive.
5. Circular Saw: Equipped with a metal-cutting blade, a circular saw can make straight cuts in sheet metal.
6. Jigsaw: With a metal-cutting blade, a jigsaw can be used for curved or intricate cuts in sheet metal.
Remember to wear protective gear and follow safety guidelines when cutting sheet metal to avoid injuries.
Sheet metal, commonly found in 18- to 28-gauge thicknesses, is a thin, galvanized steel material used for making ducts. It can also be found in aluminum, copper, and brass, and can be cut using the same tools and techniques. While a single pair of snips can make almost any cut in sheet metal, there are specialty versions available for smoother cuts and curved cuts.
Ordinary metal snips are suitable for cutting most types of sheet metal.
Image Credit:
Wiss/Home Depot
Tools for Cutting Sheet Metal
When cutting sheet metal, it is crucial to wear a pair of leather work gloves to prevent injuries. The next essential tool is a pair of compound tin snips, also known as aviation snips. Unlike traditional tin snips, these snips have short, powerful jaws that can cut through 18-gauge sheet metal and the seams on sheet-metal ducts. They are versatile and can also be used for cutting other sheet materials such as plastic, leather, and rubber. Investing $10 or $12 in a decent pair is worthwhile.
The jaws of metal snips have fine teeth for gripping the smooth metal.
Image Credit:
Wiss/Home Depot
Aviation snips come in different types. The standard straight-cut versions have straight pointed jaws and yellow handles. They are designed for straight cuts but can also handle curved cuts. For straight cuts and occasional wider curved cuts, the standard straight-cut snips are sufficient.
There are also right-cut and left-cut versions of aviation snips. Right-cut snips are ideal for right-handed users as they are made for straight cuts and right curved cuts. They have green handles. Left-cut snips, with red handles, are suitable for left-handed users as they make straight and counterclockwise cuts. Right-cut and left-cut snips are more effective for curve cuts than straight-cut snips and offer better maneuverability with their offset geometry.
Straight-cut aviation snips.
Image Credit:
Wiss/Home Depot
If you frequently need to make long straight cuts in relatively thin sheet metal, you may also consider purchasing a pair of standard tin snips. These snips resemble scissors and have large metal handles. If you already have an old pair, you can use them or opt for a newer, sharper pair. Standard tin snips provide cleaner and faster straight cuts compared to aviation snips, but they are less versatile.
Tips for Cutting Sheet Metal
When it comes to cutting sheet metal with snips, it can be compared to cutting fabric with scissors. However, sheet metal is a much tougher material with sharp edges and corners, so it is important to wear gloves for safety. As you cut, the sheet metal can obstruct your snips, making it difficult to keep them straight and position your hand for efficient cutting. To minimize this problem, use your free hand to peel or bend the waste material out of the way. Here are additional tips for different situations:
Right-cut aviation snips are often identifiable by their green handles.
- Use a permanent marker to mark your cutting line. For basic cuts, a “fine point” Sharpie works well, while an “ultra fine point” marker is ideal for more precise lines that will be less visible afterwards.
- Before each cut, fully open the snips’ jaws and align them with your cutting line. The back of the jaws, where the two halves cross, has the most cutting force. If the material is difficult to cut, open the jaws all the way and apply force when making the cut to prevent the material from slipping out. Always align the jaws to ensure accuracy.
- In most cases, avoid closing the jaws all the way. Doing so tends to bend the metal at the tips of the jaws, where they have the least cutting power. Instead, stop cutting as you approach the tips, then fully open the jaws again to prepare for the next cut.
- For interior cutouts that do not touch the edge of the material, start by using a chisel or flat-blade screwdriver and a hammer. Place the chisel edge or screwdriver tip inside the marked cutout and lightly tap it with a hammer to create a short gash. Then, insert the jaw of the snips into the gash to begin cutting out the desired shape.
- When cutting small holes, up to approximately 2 inches in diameter, use a hole saw and a portable drill. Mark the center of the hole on the metal, and securely clamp the sheet over a thick piece of scrap wood, such as a 2 x 4. Create a dimple at the center mark by lightly tapping it with a punch or nail and a hammer. Be careful not to break through the metal. Position the drill bit of the hole saw onto the dimple and slowly drill out the hole, similar to drilling wood. Use a slow drill speed to prevent overheating the hole saw.
Left-cut aviation snips can usually be recognized by their red handles.
