Kumihimo is an ancient Japanese braiding art. The braids are still used nowadays as ties for yukata and kimonos. I learned how to braid on two looms, the Marudai and the Takadai, with Giovanna Imperia.
The Marudai stand consists of a round wooden piece with a hole at its center, called the mirror, mounted on 4 legs. The braider sits or kneels in front of the stand and moves threads weighted with bobbins (the tamas) over the mirror. I'm using tamas of 70g each, and embroidery thread. Different patterns call for different weights and more tamas. A bag full of weights (marbles, fishing weights) is attached at the starting point of the braid to counterbalance the weigth of the tamas. The weight in the bag depend on the combined weight of your tama, basically you want your point of braiding to be at the top of the hole, to get a firm braid.
The weaver moves the tamas on top of the Maru-Dai, crossing the threads in a predefined pattern, the weights produce the tension necessary to form an even tight braid. This is very rhythmic, very peaceful.
The braids created on the Marudai have a small diameter with a polygonal section (the section shape depends on the pattern used).
The Takadai is a large frame in which flat larger braids are created in a process similar to weaving, but with more flexibility in the pattern than an occidental loom.
The width of the braid depends on the number of threads, and is limited by the width of the torii, the wooden rod at the top of the Takadai. As with the Marudai, the threads are attached to weights (the tamas), that take care of the tension. The threads are woven following complex patterns, and a wood sword is used to gently tap the threads in place. The weighted threads are placed on the arms of the takadai, kept in place by pegs(komas). Some patterns are made using one arm on each side, others are using the 4 arms.
Special braids, called pick-up braids, are made with the 4 arms and the threads are woven to create patterns on the braid (geometrical designs, flowers, letters, etc.). These braids are usually bi-color, one color is set on the lower arms and another color is set on the upper arms, while weaving the threads are exchanged to create the pattern.