Cutting is an important part of sheet metal fabrication, removing parts of the original metal to achieve a desired shape. Several different techniques can be used to accomplish this, and it is helpful to understand the differences.
Slitting
Slitting is often the first part of the kind of cutting process practised by professionals such as those at https://dkmsheetmetal.co.uk/, using a pair of opposing circular blades to divide a coiled sheet of metal into precisely sized pieces.
Shearing
This basic process places a large piece of metal into a machine. There are two blades, and the upper blade slices the metal into smaller pieces through downward force.
Punching
Punching includes piercing to create a single hole, perforating many small, close together holes, slotting with a rectangular tool to make a slit, lancing with a single blow that both cuts and bends, notching the edge or nibbling more complex designs with overlapping punches.
Blanking
The metal is held in place whilst a punch of the desired shape is applied. This allows for the production of smaller details.
Deburring
Burrs are the rough edges left after a cut. They are traditionally removed with handheld tools and mechanical abrasion, though electromagnetic and electrochemical methods have also been used.
Trimming
Similar to deburring, but using a machine rather than a handheld tool, trimming clears away any remaining excess to finalise the edges and borders.
Each method of cutting serves a different role. Being able to distinguish between them will make it much easier to choose the most appropriate technique for a specific project.