All this occurs on a molecular level.
Binding sheet metal to hard plastioc.
This is done through the application of force on a workpiece.
Bend the metal with your mallet.
The force must exceed the material s yield strength to achieve a plastic deformation.
Your tapping should start at one end of the evolving bend.
Holding the sheet material evenly with both hands both in protective gloves push the sheet up gently bending it against the line of the jig as shown in the photo above.
You can see this in the fogging of some clear plastics on the outside surface.
Do this until it bends toward the form block and achieves your desired angle gradually and evenly.
Bending is one of the most common sheet metal fabrication operations.
When a bend is made in sheet metal or plastic the outside of the material structure expands while the inside compresses.
Commonly used equipment include box and pan brakes brake presses and other specialized machine presses typical products that are made like this are boxes such as electrical enclosures and rectangular ductwork.
To prevent damage or unsightly dents it s best to use a rubber plastic or rawhide mallet to gently tap the metal.