Sheet Metal Fabrication Techniques

Sheet Metal Fabrication Techniques

Published by Ted on Jun 26th 2019

Metal fabrication involves bending, cutting, shrinking, stretching, or welding material. Each of these methods requires different techniques and tools to get the job done.

Bending

Form bending is the most basic technique for bending metal. The metal bends over a shape or the edge of a tool such as a hammer.

A metal brake is the most precise technique. This involves the use of a clamp and a flat bar that bends the metal to the intended angle.

Cutting

Hand shears, power shears, throatless shears, angle grinders, and saws provide suitable options for cutting metal. Hand shears and throatless shears allow you to manually cut metal.

Power shears, saws, and angle grinders are useful when cutting straight lines. However, they tend to waste material when cutting complex shapes or around corners.

Shrinking

Tucking metal involves hitting the metal with a hammer and is the earliest technique for shrinking. A shrinker offers more precision. It includes textured jaws that grab the metal from the top and bottom, pressing the metal together.

A heat shrinker is another metal fabrication technique for shrinking. It requires you to overstretch the metal over an area and torch it.

Stretching

Using a hammer and dolly is an easy technique for stretching the metal. You hold something behind the metal and hit the other side with a hammer.

A stretcher is a mechanical device that stretches the metal using two textured jaws. A foot pedal or lever adds pressure, pulling on the metal.

An English wheel also works for stretching the metal. It includes an anvil wheel and a top rolling wheel. This device is a common choice for fabricating large sheets of metal such as automotive panels or aircraft skins.

Welding

Welding is the most common type of metal fusion. The oldest technique is oxy-fuel welding. An adjustable torch mixes acetylene and oxygen to create a controlled flame.

TIG welding requires a torch with a non-consumable electrode. This torch creates a small electric arc that melts the metal.

Most metal fabricators still use MIG welding. This method involves a motor that feeds a filler wire to the tip of a MIG gun. The wire completes a circuit when it touches the metal, creating the weld joint. Compared to other welding techniques, this creates more sparks and requires more experience to master.