Tamashigiri is the practice of test cutting using a Japanese Sword (Shinken), the origins of this practice date back to the Edo period - 17th Century.
The practice was originally intended, not to test the kenshi (swordsman) skills but more specifically a test the quality of the toshin (blade). The results of these tests were often inscribed on the nakago (tang) of the respective swords. Today, the reverse is more often common, with tameshigiri being used as a marker of actual cutting ability and technical skill.
Test cutting was originally conducted using cadaver and sometimes upon the unfortunate souls of convicted prisoners, a multitude of specific cuts were often made, many directed at the targets found in the wearing of yoyori (armour) however; further additional cuts were made as illustrated:
Today, the practice of test cutting is far less grim in reality however, a student always remains mindful of the practice's origins and affords the wara (cutting target) a degree of respect that might otherwise appear unwarranted. The act of tameshigiri is essentially the same act of cutting a live target.
Tameshigiri is now conducted primarily against rolled targets of straw, these can be manufactured from scratch if one has access to the raw material. Bundled together, trimmed and tied together to provide a target offering several cutting opportunities, the wara is then soaked in water often overnight, then drained. The result provides an approximate resistance to that of the human body (thickness and resistance depending upon the wara dimensions). Because test cutting has become a popular activity, commercially available wara are now widely used, these can be purchased ready rolled or in the form of mats which the user rolls to their own specification.
In addition to rolled mats, green bamboo is used as a cutting medium however the resistance bamboo produces requires a greater degree of skill to cut cleanly and effectively. Green bamboo may also be rolled into matted targets to simulate the greater resistance found in cutting through bone.
Safety is an important factor in the successful application of tameshigiri, one should NEVER attempt to test cut ANYTHING without first having instruction from a qualified and experienced instructor