This test method covers determination of the ductility of grain-oriented silicon steel by use of an apparatus known variously as a tinners brake, hand folder, or an apron brake. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. The values stated in inch-pound units are to be regarded as standard. The values stated in SI units, shown in parentheses, are for information only.