Sheet metal is used to make things that we use every day, from major appliances to simple decorative items. As its name implies, sheet metal comes from the steel mills in sheets around 200 feet long. It needs to be cut down into smaller lengths. Whether using tin snips, computer controlled machinery, or large power shears, it is cut again into usable sizes and shapes. The computer controlled cutting machines make precision cuts that are amazing.

Two types of precision cutting are punching and laser cutting

Punching is the older way of the two. A die consisting of two intermeshing plates are mounted opposite each other. A piece of sheet steel is placed between them. The punch is activated and the two plate punch cut the steel into the form the die was designed in. Punch cutting is faster but harder to change for repetitive assembly line cutting. Air conditioner housing and car hoods are just some of the examples of punch cutting.

Laser Cutting

Laser cutting is a more modern way of cutting sheet metal. A CNC or Computer Numerical Control monitors a laser to heat and cut the sheet metal. Oxygen is blown through the same nozzle as the laser beam. The oxygen/laser combination allows for a faster cut than laser alone. The CNC can cut very precise shapes and the pattern can be changed faster than the punch cut.

Hand tools

Sheet metal has been used since before machines were invented. Cutting and forming sheet metal can be done with hand tool. Although a hammer and knife, or axe can be used to cut sheet steel, it is dangerous and it is highly discouraged from using that method. Try using tin snips instead. They are popular with hobbyists. When working with tin snips, remember that the metal is unforgiving. The metal is stiff and the edges are sharp enough to cut with just a slight brush of the skin. Cutting curves and shapes with tin snips is difficult. Remember to use the proper snips and study up on the proper techniques of using tin snips.

Hand tools come in different shapes and size for different applications. The same is true for tin snips. Offset compound tin snips are recommended for beginners. The offset jaws allow you hand to stay above the sheet metal instead off passing through the cut in the steel. The compound jaw action lets you cut thicker steel faster and easier. Be advised; tin snips are color coded.

Snips cut curves in the counter clockwise direction. Green tin snips cut curves in the clockwise direction. I guess that means there is left handed and right handed tin snips.

Finally, a sheet metal cutting tool that is used by construction workers and professional sheet metal workers are aviation snips. Unless using aviation snips with offset jaws known as upright snips, the user of aviation snips must put his/her wrist into a precarious position when holding the metal to be cut.