Maintenance of Rope
Like every item on a rigging system, ropes have to be maintained in order for them to retain their strength and function properly. Taking the proper precautions while using and performing regular maintenance on your ropes will keep them working for a long time.
1. Uncoiling Rope
New rope in a full coil is stiff and has a tendecy to stay curled. The proper way to uncoil it is to lay the coil down on its side so the inside end is down near the floor. Begin uncoiling the rope from the inside end, turning it in your hand to remove the excess twist. This method will keep the rope from tangling and kinking.
2. Coiling Rope
When you are finished working with a rope, coil it properly. Never coil a twisted rope over your hand and elbow, as this will put excess twist in the rope and cause kinking. Right-lay rope should be coiled clockwise, or “with the sun”.
Care should be taken to remove all excess twist. Do this by turning the rope as it is being coiled. If the rope is properly coiled and in balance, no twisting or kinking of individual coils should occur. Rope can be coiled over an open hand, on a pin of the pin rail, or if too long and heavy, flat on the floor. When coiling a rope on the floor, be sure that the top coils do not get larger and fall around the bottom coils. This will cause kinking and tangles the next time you use the rope.
3. Storing Rope
On a fly floor, rope should be dressed or properly coiled and hung on a belaying pin. Do not leave it lying around on the floor. It will pick up dirt and is dangerous for people to walk on.
Sometimes, rope is stored near or on the grid because spot lines must be rigged from there. Provide some method to hang the rope, preferably on wood pegs, so that air can circulate freely through it. Natural-fiber rope absorbs moisture from the air. If it is hung on a metal peg or on a metal surface, the metal can oxidize and hasten the deterioration of the rope.
4. Keeping Rope Clean
Grit and dirt work into the fibers of the rope and break them through abrasion. Dust absorbs the dressing put on the rope during manufacturing and dries the rope out, thus shortening life. When a rope gets dirty, wash it in clear water. Pass it through a tub of water, and swish it around until the dirt comes out, or hose it off. A mild dishwashing detergent can be used but should be thoroughly rinsed out.
5. Drying Rope Properly after Wetting
Because Manila (Manila Rope is a type of rope made from manila hemp) is an organic substance, it will rot or mildew if stored wet. Hang it loosely where dry air can circulate, and dry it thoroughly. Inspect the rope for dryness by untwisting it a bit and touching and smelling the fibers. Wet Manila Rope has a distinctive odor. Polyester will not rot, but it still needs to thoroughly dry after wetting.
6. Protecting Rope from Chemicals
Acidic and alkaline substances will harm Manila fibers. Grease and oil destroy the fiber friction that holds rope together. Paint solvent dries out rope. Polyester rope is not as affected by harsh chemicals. Nevertheless, keep all rope away from chemicals.
7. Avoiding Rope Overload
Once a rope is stressed beyond its elastic limit, it loses its original strength. Use the right size rope for the job at hand. If it is overstressed, take it out of service, and destroy it. Note: if you throw away a rope, cut it up. If someone uses your cast-off rope for load-bearing or life-line applications, and it fails, you could be liable. Always cut up old rope before throwing it away.
8. Avoiding Sharp Bends and Small Sheaves
A rope tied around a sharp corner of a heavy load can be strained at that point, which will permanently weaken the rope. Pad all sharp corners. When a rope passes around a sheave, the rope bends as it moves. Be sure that the pulley has a large enough diameter so that the rope will not be severely strained. Maintain a minimum ratio of sheave diameter to rope diameter (D/d ratio) of 8:1.
9. Avoiding Abrasion
Do not drag rope over rough surfaces. Doing so will cause unnecessary wear. Sheaves or pulleys must be grooved for the size rope being used. If the groove is too small, the friction on the rope will cause it to wear and weaken. Be sure that blocks are aligned so that the rope does not rub on side plates.
10. Avoiding Shock Load
Jerking a rope or suddenly dropping a load (such as when a fouled piece of rigging falls free) can easily break a rope. One of the reasons that the safe working load is much less than the breaking strength of a rope is to allow for this possibility. The greater the shock load, the easier it is to break the rope. If a rope is subjected to a severe shock load, it may be stressed beyond its elastic limit. If a rope has been shock loaded, take it out of service, and destroy it.
11. Adjusting Rope for Humidity
Humidity affects Manila rope. As the humidity increases, the fibers absorb the moisture from the air and swell. The rope gets thicker and shorter. As the humidity drops, the rope dries out, the fibers shrink in diameter, and the rope gets longer. In environments with significant changes in humidity, such as theatres with intermittent air-conditioning or outdoors, multiple-line hemp sets must be trimmed before every performance. Because the lines are different lengths on multiple-line sets, they will not shrink or expand evenly. A hanging drop that is level at low humidity will get high on the long side as the humidity increases. In this case, the load is free to move, and no damage will be done to the rope.
In some instances, where the load can not move, such as a guy rope, permanent damage to the rope may occur owing to shrinkage caused by dampness. The rope can get stretched past its elastic limit and lose some of its tensile strength. In such cases, it is important to remember to slack off the tension on the rope as it contracts. Polyester rope is not affected by humidity and therefore needs no adjustment.
12. Inspecting Rope
Using the rope until it breaks is irresponsible. As you use it, be aware of it. Look at it; feel it! If something does not feel or look right, replace it, rather than take a chance. Visually inspect all rigging rope over its complete length on a regular basis. This is best accomplished by unrigging it and inspecting the entire length by hand and eye.
After this reading, are you feeling more confident about maintaining your ropes now? Any comments or concerns, please contact us at firstname.lastname@example.org. We are a wholesaler for rigging hardware products. Thank you for your reading!