The Mengane (面金)is one of the most essential parts of the Men (面) as it protects the face from the impacts (Shinai, Kote, Mengane ...). It imports a lot in the weight of the Men, which when too heavy can cause discomfort or, even worse, damage the cervical of the user.
The Mengane structure
The Mengane is composed of 14 Yokogane (横金) for an adult size, and 13 for a child one. From the top, the space between the 6th and 7th Yokogane, for an adult size, is called the Monomi (物見), and between 5th and 6th for a child one, this space his wider to offer better visibility.
The Yokohigo above the Monomi are called the Kami (上), and the ones below are called Shimo (下).
The central part is the Nakahigo (中ひご), it is traversed by the Yokohigo and reinforces the Mengane.
The outer part where all the Higo are attached is called the Daiwa (台輪). The Higo are attached to the Higo by welding them together.
The Kami receiving the Shinai strikes are 5.5 ~ 6 mm thick to be more resistant, as well as the Monomi. The Shimo, to make the Men lighter are 4 ~ 5.5 mm.
The Nakahigo, to improve the visibility, is thicker on the outside than the inside.
The Mengane materials and properties
As explained, the Mengane play an important part in the weight of the Men. Thus, Bogu maker to create lighter Men have started to use lighter metals. However, this lighter metals can be less strong than heavier Mengane like, Steel or Titanium one, and, thus, not react correctly to intense training.
Different alloys or metals can be used for Mengane, Brass alloy, German nickel, Duralumin (Aluminium-Copper Alloy), Stainless Steel, Titanium ... But the most common ones are made from Duralumin of various quality, Titanium, or a hybrid of both.
The outer Mengane was, in the past, polished or left as it was. Nowadays, it is mainly coated with Nickel or Chrome. Some uncommon coating like Gold one also exists for antimicrobial Mengane.
The inner Mengane is most of the time the paint in red/ vermillion to nake the Men brighter.
When doing Taiatari important stress is exerted on the Mengane and in some case, the Higo can bend. Once they have started to bend, they can easily be bent even more. This situation lends to metal fatigue which can be the cause of accidents.