Whether you’re making a patch panel or fabricating a new design from scratch, cutting sheet metal can be a challenge. The key to a good, clean cut is having the right tool for the project. Some tools are great for long, straight cuts while others are made specifically for making tight contours.
Below are six general categories of tools for cutting sheet metal. These include shears, circular saws, reciprocating saws, nibblers, disc cutters. Many of these are available in either electric or pneumatic drive, as well as manual operation in some cases. One tool we intentionally left off this list is plasma cutters. While we love the power and speed of a plasma torch, we feel that requires a different set of skills than these hand and power tools.
Hand shears/snips
When it comes to cutting fine details in fairly thin materials, you can’t beat old-school hand shears. Whether you’re talking about simple tin snips (essentially heavy-duty scissors) or more complex aviation snips, they’re a toolbox staple. Both are great for making small, quick cuts and offer great agility and flexibility. There’s no material loss from cutting with these shears, but you’ll need to be mindful of how the cut may curl one side of the work. Hand shears can be a workout for your hands, making them less ideal with thicker material or longer cuts.
Power shears
Similar in function to hand shears but backed up with the strength of electric or pneumatic power, these can be a great option for number of cuts. Many handheld power shears use three blades – a moving central blade and two stationary shoulder blades. This design prevents the work from warping during cutting, but it sacrifices a thin ribbon of waste material in the process. This is typically only around 1/8” or so, but it must be factored in to achieve precise cuts. The length of the cutting blade will dictate how tight a radius can be cut, but most allow for generous contours.
Bench-mounted shears, as well as power-operated throatless shears, offer a no-loss cut with the ability to handle larger work with precision.
Circular saws
When you need long, straight cuts in thicker material, it’s hard to beat a pneumatic or electric circular saw. When cutting sheet metal, the key to a smooth edge is having the correct blade. A fine-tooth blade with a high tooth-per-inch (TPI) count is often preferred. However, another option is the more aggressive (lower TPI) type with hardened teeth specifically for sheet metal. Handheld body saws are a fast, clean way to cut out floors and body sides. You lose only as much material as the thickness of the blade, but the cuts need to be essentially straight to prevent binding.
Rotary discs
A close relative of the circular saw is the rotary cutter like this adjustable-head cutter-off tool. The biggest difference is that rotary cutting discs don’t have teeth, but rather an abrasive edge that makes the cut. Also, cutting discs are often much smaller in diameter (3″ or less) and thickness than a saw blade. These two differences allow for smoother, more agile cuts than a saw. The downside is that rotary discs wear much more quickly and may even be consumed during a long cut.
Reciprocating saws
Another common shop tool that’s great for cutting sheet metal is a reciprocating saw. With their shallow, thin blades, these are best for cutting complex contours or making cuts in tight places. Their relatively short strokes are ideal for cutting sheet metal or other thin materials. Understandably, they require blades with a high tooth count (24-32 tpi) to prevent gouging. Material loss from cutting is quite minimal and the tool typically doesn’t alter the contour of the work.
Nibblers
Whether powered by electricity or air pressure, nibblers work in a similar way to reciprocating saws. However, instead of a flat blade with a row of teeth, the nibbler uses a reciprocating hardened pin with a nibbling face. As it travels up and down, it “bites” a small chunk out of the material with each cycle. In the process, it spits out tiny chips of the removed metal. The diameter of the bit determines how much material is lost, but it’s minimal. Because the bit is circular, the nibbler can be turned in place, making it one of the most agile cutting tools available.
