Is size important? Rope!

Posted on Sat, 14 September 2013

The question I am often asked is what length, type and thickness of rope should I use? If you want a strict answer, kinbaku is typically performed with equal length ropes of 7m-8m. Whilst there may be historical reasons for the length, it is certainly easy to handle and means you never have to worry about which rope you pick up. The standard forms (katas) are designed to work with these lengths, although sometimes slight adjustments in length can aid in tying particular elements more elegantly. [private] For example, I prefer a rope nearer 8m for tying an Osada Steve style takate-kote, even for a small model, as it allows me to tie and cinch the first wrap with one piece. There is a lot to be said, however, for ensuring a rope is no more than 4 x the span of your out-stretched arms. This means the rope can be pulled through in one movement, as you will be using it doubled, which is fast and fluid. As ropes can be extended by simply forming a lark’s head on the additional rope and slipping it over the knotted end of the last, there is no need for a selection of extra long lengths. If you make your joins as late as possible and, when untying, remove them as soon as you can, it will save much pulling through of rope and speed up your work.

In Japan, jute seems to be the rope of choice, although is not used exclusively. It is easy to see why, as it handles beautifully and is very light compared to hemp. Due to the nature of kinbaku technique, the rope must be ‘grippy’ to hold knots well and have minimal stretch. This means that natural fibre is ideal, since many synthetics can be too slippery or too stretchy. Also, it is more difficult to cause rope burn with a natural fibre and it doesn’t heat up as much when pulled across skin. Twisted 3-ply rope is much favoured as it leaves characteristic indentations when it is removed, something which many people find as beautiful as the bondage itself.

Interestingly, I have recently learnt that 'Japanese hemp' is a misonomer as, apparently, very few use hemp rope in Japan. The Japanese language does not differentiate between jute and hemp and it is merely a quirk of on-line dictionaries that first component of ‘asanawa’, ‘asa’ has been translated as ‘hemp’ rather than jute (nawa meaning rope). Source: . Some confusion might also be due to the two meanings of hemp. Most of us associate hemp with rope made from the cannabis genus. However, there is also another more generic meaning which refers to any rope made from bast fibre, which refers to the fibres that grow on the outside of the woody interior of the plant's stalk, and under the outer most part (the bark). Under this definition, jute could also be called hemp. (Merriam-Webster: a fibre (as jute) from a plant other than the true hemp ; also : a plant yielding such fibre).

I’m not a big fan of hemp as I find it smelly, heavy and rather dead in my hands but I know many people swear by it and go into ecstasy at its farmyard aroma. I also find that it can have a rather ‘linty’ appearance, especially with use, whereas jute will become polished. The feel and look of jute and hemp can be improved with treatment. In most cases, this involves boiling or hot washing, although I would avoid doing this to loosely woven jute, e.g. some Japanese rope, as it can open up the weave too much. My referred washing method is a dishwasher as, due to the lack of agitation that you would get in a washing machine, the twist stays tighter. Once washed, I dry the rope under tension, strung out like a washing line. When it’s dry, I will then burn off the ‘fuzzies’ over a gas cooker. Finally, I will dampen a rag with a little tsubaki oil (Camellia Japonica) and draw the rope through it several times. Tsubaki is a traditional treatment for wood and metal, being a natural preservative. It’s also very popular cosmetically in Japan for hair, nails and skin. Although many Japanese nawashi favour bayu, not all Westerners are comfortable using something made from horse fat. Furthermore, it has the potential to go rancid.

If you don’t want to go to the hassle of treating rope or cost of pre-treated, 3-ply twisted cotton is a good economical option. It can also be the solution for those with allergies. However, this does not have the strength of hemp or jute, so should not be used for load-bearing work, e.g. any form of suspension.

As for thickness, around 5-6mm is used for suspension and thinner cord is often used for floor-work or detail bondage, e.g. 4mm. I find that anything more than 6mm becomes hard to work with and that it produces bulky knots, which can be ugly and cause discomfort.

All in all, it is what works for you but these ‘standards’ have emerged from a lot of experience. There is good reason why they are the way they are. Like many things in life, it's not so much the size as what you do with it that counts ;-)