Equipment concerns

Use appropriate rope. The whole idea behind the natural fiber ropes is that they hold their knots and that makes for much easier, safer, sensual and attractive bondage. They are not as strong as climbing rope but most of use don't really need the margin of a 3000 pound rated rope. A clean, well inspected twisted hemp or jute rope will provide sufficient margin. Manila rope is treated with chemicals that can cause skin irritation or worse. Nylon, and poly ropes can be quite slippery. The idea of a knot is to take advantage of friction component of the rope to make it hold. Using rope that does not offer sufficient friction for the purpose is something you may want to reconsider.

Rope will break (most often when it is least expected) breaking rope hurts in several ways.  That said, twisted rope will NOT break one strand at a time like you see in the movies.  Rescue rope is tossed when it is stressed because you can’t see what has happened inside the core.  Twisted rope is naked.  Plus it makes pretty marks.

Tensile strength numbers are approximate. Different manufacturers make different claims. This is for new rope, your mileage my vary). Working load is generally accepted to be about 20% of the tensile strength shown.  For example the maximum working load for 3/8 hemp is about 140 pounds. 

OSHA would not allow you to swing a hammer from your belt with hemp rope if you were wearing steel toe boots and we all know that twooo Shibari Masters never wear shoes.

	Caution 1. Safe loads are recommended guidelines only. 2. Specs are based on labratory tests of new and unused ropes of current manufacturers. 3. Once rope is put into service it is continuously deteriorating. 4. Natural fiber rope will deteriorate in storage even under ideal conditions. 5. Treating hemp rope reduces its tensile strength approximately 20% cumulatively.

*I have tested a lot of hemp rope and generally the tensile strength of 8mm is usually between 900 and 1000 pounds. This leads me to believe that the manufacturers tables may have a percentage of fudge factor built in. I tested some flax and it was in the 700 pound neighborhood and I tested some of Twisted Monks 4 strand and it was over 1200.

Knots make it break faster
 Let us say that a new rope breaks at 1000 pounds in a test machine.  If you tie a square knot in the middle of the rope and retest it, experimentation has confirmed that the rope will now break at the knot at an average of 500 pounds or 50% of nominal tensile strength.

We don’t tie up test machines so there are knots of some sort involved most everywhere.  The way much of Shibari is done is by doubling the rope and passing the running end through the bight to form a larks head.  The larks head and the reeve point of a truckers hitch are types of a double bend.

	•   Bowline 70% •   Anchor bend 60% •   Half hitches 60% •   Square knot 50% •   Sheet bend 60% •   Carrick bend 60% •   Double bend 20%

(so it follows that the maximum working load for hemp with a double bend is about 30 pounds)

Clips, carabineers, releases, hooks, eye bolts, structures, etc should all be inspected to ensure that they are designed for the purpose, are free of defects and possess sufficient strength.  If it did not come from a climbing hardware supplier it should have at least come from a marine hardware supplier.  I saw a beautifully designed beam suspended attractively from Home Depot type carabiners and quick release snaps of the type shown. I have no doubt that the carabiners will hold but that style of snap comes in several varieties. Most are unrated horse tack that are designed to break free if a shock load is applied to it.

Keep in mind that in many cases we are recreating ties depicted by an artist who may be working from historical artifacts, all the while attempting to use the practices of the time to arrive at some hot kinky sex. Remember also that these ties were used to secure suspected or condemmed criminals and military prisioners who presumadly had less value to them than your CLWL (Cutle lil working load) expects you to show.