Definition
A sheet metal shop tool used to make straight, sharp bends along the edge of a piece of sheet metal. The metal is clamped between a stationary jaw and a folding leaf, and the leaf is swung up to bend the exposed edge to the desired angle.
Plain English
A bench tool that grips a flat piece of sheet metal and folds one edge cleanly to a chosen angle.
Context Anchor
Seen in aircraft maintenance and repair, especially when making or repairing metal panels, covers, and brackets.
Derivation
Called a 'bar folder' because a long bar (the folding leaf) is what swings up to fold the metal. The name describes the action of the tool.
Why Pilots Care
Enables accurate forming of metal parts that maintain aircraft structural integrity and aerodynamic surfaces.
Intuition Check
A bar folder is not a file folder or storage item. In aircraft maintenance, it is a tool for bending sheet metal.
Example Sentence 1
He used the bar folder to put a 90-degree flange along the edge of the aluminum patch before riveting it to the skin.
Example Sentence 2
Before riveting the new access door, he folded the flanges on the bar folder to match the existing contour.