Line Cable-laid line usually consists of three right-hand hawser-laid lines twisted together in a left-hand direction. This type is especially useful in heavy construction work, because if it tends to untwist, it will tighten any regular right-hand screw connection to which it may be attached; hence, its use provides an added safety feature.
The size of a line larger than 1 3/4 inches (44.5 mm) in circumference is generally designated by its circumference in inches. A 6-inch (15-cm) manila line, for instance, would be constructed of manila fibers and measure 6 inches (15 cm) in circumference. Line is available up to 16 inches (40 cm) in circumference, but 12 inches (30 cm) is normally the largest line carried in stock. Anything larger is used only on special jobs (fig. 4-3).
Line 1 3/4 inches (44.5 mm) or less in circumference is called SMALL STUFF, and size is usually designated b y the number of threads (or yarns) that make up each strand. You may find 6- to 24-thread small stuff, but the most common sizes are 9- to 21-thread (fig. 4-3). You may hear some small stuff designated by name without reference to size. One such type is MARLINE-a tarred, two-strand, left-laid hemp. Marline is the small stuff you used the most for seizing. When you need something stronger than marline, use a tarred, three-strand, left-laid hemp, called HOUSELINE.
Figure 4-3. - Size designation of line.
If you ever order line, you may find that you have to order it by diameter. The catalog may also use the term rope (rather than line).
ROPE YARNS for temporary seizings, whippings, and lashings are pulled from large strands of old line that has outlived its usefulness. Pull your yarn from the middle, away from the ends, or it will get fouled.
If you expect the fiber line you work with to give safe and dependable service, make sure it is handled and cared for properly. Procedures for the handling and care of fiber line are as follows:
CLEANLINESS is part of the care of fiber line. NEVER drag a line over the ground nor over rough or dirty surfaces. The line can easily pick up sand and grit that can work into the strands and wear the fibers. If a line does get dirty, use water only to clean it. Do NOT use soap because it takes oil out of the line.
AVOID pulling a line over sharp edges because the strands may break. When you have a sharp edge, place chafing gear, such as a board, folded cardboard or canvas, or part of a rubber tire, between the line and the sharp edge to prevent damaging the line.
NEVER cut a line unless you have to. When possible, always use knots that can be untied easily.
Fiber line contracts, or shrinks, if it gets wet. If there is not enough slack in a wet line to permit shrinkage, the line is likely to overstrain and weaken. If a taut line is exposed to rain or dampness, make sure that the line, while still dry, is slackened to allow for the shrinkage.
When nylon line is properly handled and maintained, it should last more than five times longer than manila line subjected to the same use. Nylon line is also lighter, more flexible, less bulky, and easier to handle and store than manila line. When nylon line is wet or frozen, it loses little strength. Additional y, nylon line is resistant to mildew, rotting, and attack by marine borers.
If a nylon line becomes slippery because of grease, it should be cleaned with light oils, such as kerosene or diesel oil.Continue Reading