The Rokkaku Kite

MBK Dowel Rokkaku

Although there are differences between East and West, rok battles involving individuals or teams are still being organized in various parts of the world.

In Japan, the kites are often large and made from traditional construction materials. We were fortunate enough to see a few examples of the real thing at a kite festival here in Adelaide one year.

Talking about that kite festival ... for several years, a collection of identical small white rokkakus were pulled out each year for a crowd-pleasing item—the Rokkaku Challenge! One year, I captured an entire bout on video. The soundtrack also captured the running commentary coming through the PA.  

In the USA there is also a thriving rok-battle scene with its own rules and kites made from more modern materials.

The last kite remaining in the air wins! Strings are either sawn through, or kites tangle and come to ground together.

Rok featuring applique decoration

• The overall size of both traditional and Western rok-inspired kites doesn't vary a whole lot, in general.
• The basic outline is always the same, with minor variations in proportions.
• Traditional construction materials hardly vary at all, which contrasts with the variety of modern kite-making materials.
• Traditional rokkakus are designed to fly without a tail in all conditions.
• Traditional roks are artistically decorated and shop-bought versions are available in very vivid modern designs.
• The number of bridle legs varies, with four being by far the most common number.
• Traditionally, the sail was hand-made paper but these days ripstop nylon is commonly used.

Here's a few comments on each of the above points:

Size. Most plans and write-ups for rokkaku kites feature a vertical spar around 1.8 meters (6 feet) long. This is because the most commonly accepted size for Rok Battle kites is 6 feet. Kites bought from stores vary a bit more with one well-known shop selling sizes from 1.2 meters (4 feet) tall through to 2 meters (6 feet) tall. There's that 6-foot measurement again! There also seems to be the occasional bigger home-made rokkaku kite, say 7 or 8 feet tall, flown for recreation. And of course, the kite aerial photography (KAP) crowd have always loved their super-big stable roks!

Shape. Rokkaku kites all look pretty much the same in outline, with six corners, a long vertical spar, and two bowed cross-spars. There are two widely-used proportions in particular, named 4,5,6 and 3,4,5. For example, 3,4,5 means that the kite is 5 units tall, 4 units wide, and the main body—the rectangular bit—is 3 units tall. That means the cross spars are 1 unit in from the top and bottom.

Construction. The Japanese like to refer to the kite frame as the "bones" and the sail material as the "skin"—sounds logical to me! A modern rokkaku kite might have pockets in the sail, into which the ends of the spars are inserted. Then the cross spars are bowed, and the kite is ready for flight. There's not much to it really; it's a small price for having something collapsible and easily transportable. Browsing around, I came across three separate methods for holding a bow in a cross spar:

• The truckie's knot: Without going into detail, this is an easy way to hold tension in the line while tying it off at one end of the cross spar.
• Using one line from each end of the cross spar: A button on one and loop on the other allow the lines to be connected in the middle and hence hold the tension.
• Using a slider with three holes: With a slight twist, the line moves easily through the slider, but let it go and it holds the tension firmly. One end of the line is tied off at the third hole, after passing around one spar end.

One clever idea used by some designs is where the vertical spar remains attached to the cross spars. However, it separates in the middle, so each section can be swung around parallel to the cross spar to which it is attached. In this state, the whole thing can just be rolled up like a mat. Easy.

Being able to alter the amount of bow easily, as with the three-holed slider, is handy. This way, the stability of the kite can be tweaked to suit the conditions.

Tails. Usually, roks are flown without tails. However, a tail can be useful in strong winds. People who suspend expensive cameras from their kite line are particularly keen to have the kite good and stable in strong winds!

Decoration. Firstly, some modern methods could be mentioned. Strips of different-colored material can be joined together before the outline is cut. The appliqué technique involves sticking light but colorful cutout patterns onto the sail material. Screen-printed sail material can be used. These methods can be seen in both shop bought and homemade kites. Nearly all traditional Japanese kites were brush painted with bright-colored natural dyes and black ink. The shape of the rokkaku kite really lends itself to displaying a face of some sort. I've seen everything from people to eagles' heads!

Bridle. When it comes to bridles, there is some variation. Generally, a four-leg bridle is sufficient for the standard 2 meter (6 foot) rok. The bridle lines attach to the cross spars, midway between the vertical spar and the edge of the kite. Kites this size or larger can benefit from an extra one, two, or even three bridle lines attached to the vertical spar. This helps the spars resist bending out of shape in strong winds.

Sail. A traditional rokkaku kite used washi paper that was hand made. These days, ripstop nylon or Tyvek is a common choice for the larger kites. Smaller kites made in workshop sessions often just use plastic or tissue paper.