Leader cord, it's what I call the loop that connects the braid to the anchor (or counterweight for marudai), and I’m sure that there are other names for it. Used in kumihimo to quickly attach and detach braids from the dai with minimum waste of the braid. Its use in kute-uchi is a bit more problematic as there is no clear visual or written evidence of their use. In fact, a few drawings (all of which are Edo reproductions of earlier drawings) of kute-uchi appear to have the braid tied to the anchor and in one drawing wrapped around the anchor with the excess braid dangling*. But there are several other drawings and paintings where the braid is represented by a single line from the braider to the anchor, with the line simply ending at the anchor.
We do know from comparing artifacts with the drawing and paintings that artists often took liberties in representing what they see. As noted above, several Edo drawings of Japanese arts, crafts, and daily labors are reproductions of earlier drawings. In preparing for this post, I was looking for a pair of nearly identical drawings from two different sources but because of the difficulties of adding multiple photos, here is a link to one from the 15th Century on Masako’s website, http://www.lmbric.net/n6/n6.html. Masako doesn’t give any additional information on where one can find the 15th Century scroll. And below is one from Japanese Craftsmen dated to about 1657 in which shows a nearly identical scene. Some of the different details are obvious, but a few subtle differences in where the braid joins together and the location of the uprights for the beater sword shows that artists weren’t concerned with directly copying the previous drawing. I’ll get into more about the artistic license with drawings when I post about building a foot-beater so let's move on.
What we find missing is a definitive way of attaching the braid to the anchor, nearly all the images show the braid just ending at the anchor. A few images show what looks like a bow on the opposite side of the anchor. Is this because the braid goes through the anchor and is knotted off on the other side?
Let’s presume for a moment that the images are what they show; the braid is attached to the anchor directly. Using either a hole through the anchor with a knot on the other side or the braid wrapped around the anchor to knot off presents several inches and possible over a foot of wasted braid. Any thread (times the number of loops) through or around the anchor can’t be part of the finished braid and must be cut away. By itself, a convincing case could be made for this practice as it allows for the loose, jumbled beginning of the braid to be removed to present a clean, crisp beginning. But that’s not the only wasted thread in the drawing. From the anchor to the point directly above the beater swords rotational point will be a braid that is improperly beaten, loose, and out of shape. That distance is easily four to eight inches of wasted braid. If we use a conservative loss of six inches per element, two inches for attaching to the anchor and four inches between the beater sword and the anchor, that’s a foot per loop (as each loop contains two elements). And looking at images of extant braids, each loop was made of several smaller threads. Not bad for simple braids of eight loops or less, those eight foot long threads can be used to tie off the braids into manageable sizes. But on braids using up to 32 or more loops, that’s a lot of waste.
What I theorize is that a leader cord was utilized to make that attachment to the anchor and cover the gap between the anchor and the beater sword. The leader cord is reusable, and no part of the braid must be cut away to free it from the foot-beater. To explain the lack of detail in drawings and paintings, the connection between the braid and leader cord would look like a dot on the line used to represent the braid. A difficult detail to see in the first place and clouds the image, it would be easier just to omit the detail for a cleaner look.
* The particular image mentioned is from the Treasure Chest of Women’s know how. It’s an excellent example of artistic license. The image shows an integrated anchor on the heshiki (a style of foot-beater) sled. But a heshiki built like this doesn’t work as only an inch or two of braid can be made at a time before an assistant winds the braid and negating the benefit of the foot-beater. It’s also the only known image where the braid is clearly drawn like a braid and wrapped around the anchor using what looks like a slip hitch. Because the image shows some of the braid already completed it's entirely possible that any attachment method was already removed.