Hinges formed by stamping should be approximately 0.020 in (0.50mm) thick. They are less
durable in flexing but stronger in tear.
- Heated sheet/cold die: usually coupled with thermoforming. The die is cold since there is
enough residual heat in the sheet.
- Cold sheet/heated die: this approach is more energy efficient if the sheet does not require preheating
for other reasons. It also prevents distortion of the sheet, which occurs when highly
stressed sheet stock is heated.