Crown Partners
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Rope Decisions can make - or break - your business
By Rick Howland
Your personal assets are hanging in the trees – and the breeze! Is your climbing rope up to the task?
Properly cared for, a modern rope (which is synthetic due to tensile strength that is about one-th ird greater than manila plus other qualities) will last a relatively long time before normal use calls for its retirement or redeployment for less critical tasks. That means protecting it from dirt, debris and weather, handling it with care and always checking for damage.
Not caring for your rope is courting disaster. Take one story we heard regarding a champion professional climber who had climbing ropes and gear from all the top manufacturers, but went climbing one day with his favorite, old ropes. That decision became his downfall, quite literally.
When it comes to tree care professionals, the industry standard for a climbing rope is a half-inch diameter line with a minimum 5,400-pound capacity. You’ll find a standard half-inch along with nominal (approximate) half-inch lines (11mm-plus) that are engineered and manufactured to climbing standards. Regardless of the exact dimension, final selection is about personal preference.
In researching this article, we found many differences of opinion on what to do with a climbing rope that’s outlived its usefulness, but they agreed that, sooner or later, the time will come when it’s necessary to take that rope out of service.
What signs do you look for? The first and best rule regarding when to retire a rope is to contact your manufacturer for guidelines. However, there are some basics you need to know and share with your staff or co-workers as part of your ongoing training and daily prep work.
Knots can reduce a rope’s strength due to tight bends, sometimes upward of 50 percent. Rope makers say that’s one good reason not to exceed a work load limit of, say, 20 percent of a rope’s stated strength. (Again, consult your manufacturer.)
Before starting any climbing work, check to see that you’ve stored your rope clean and dry and away from heat sources. These environmental issues can attack your rope quickly, as debris cuts into the fibers, or insidiously over time, as sunlight heat and ultraviolet light slowly erode its capability and capacity. Consider a special protective rope bag; rope is a tool, after all, and should be treated like one. Check your ropes during the day, too, not just before starting work. Things happen!
The joke about when to retire a rope is that you need to do it before it breaks. Seriously, the best way to determine if it’s time to retire a climbing (or any rope) is to check it often, every day. There are no standards for retiring a rope, because so many variables come into play, such as construction, loading, bending and exposure to elements and debris, but there are a few guidelines.
Remember that as soon as a rope goes into service, it likely will “fuzz-up.” This is normal, and actually good, because the roughened rope “fuzz” acts as a cushion, an extra sleeve, actually, protecting the fibers, cord and braid beneath. Too muc h “fuzz,” though, spells wear, and it can be anywhere from 10 to 20 percent or more of fuzz along the line before it’s time to retire that rope. Consult your manufacturer and use wise, conservative judgment. If in doubt, toss it out.
An inconsistent diameter – that is, flat areas, bumps, lumps and thinning – generally means internal rope damage, likely from overloading or shock loads. This alone is enough reason to retire that rope.
Check also for consistency of texture or feel and brittleness and stiffness. Both can be signs of contamination, (as unusual discoloration can be) or possible excessive shock load.
Friction and heat are major and silent enemies. Glossy or glazed areas are signs of damage from exposure to heat sources or from heat/friction. Glossing/glazing may be the tip of a larger iceberg of damage beneath the surface. Adjacent and hidden fibers may be compromised, even though they look OK. Obviously, the greater the initial friction, the greater the heat buildup and thus the greater the chance for damaging your rope.
Ropes under tension crossing one another can be a major heat problem.
With today’s synthetic lines, variations in content and blends mean rope performances vary widely with respect to heat. Melting ranges can be from about 180 degrees Fahrenheit to 900 degrees or more. Keep ropes away from exhaust systems!
Lower-rated ropes may do the job safely and well and within spec, but since you’re using more of th e stated capacity strength, you’re likely wearing out your rope more quickly. Check for breaks and uneven rope structure.
Pulled strands may or may not be a problem. Generally, if they can be worked back into the rope, it’s ok. If not, retirement is at hand. Check with the manufacturer!
We found little new recently in terms of rope products or technology advancements, other than in coloration, which is largely a cosmetic issue. However, at least two major rope manufacturers are anticipating new product announcements later in the year.
Bill Shakespeare, marketing manager for New England Ropes, Inc., explains that there are different sizes and types of approved arborist climbing ropes that have emerged over the past few years, nominally in the half-inch class. These are 7/16-inch and 11mm sizes and some thicker, up to 13mm.
“With climbing ropes, for years the half-inch was a standard, and people have gotten used to it,” he says. “The newer sizes are thicker or thinner to provide a range to better fit people’s hands. Thinner and lighter ones are easier for some workers to throw, rig and handle, but they all do the same work.”
To illustrate his point about ease of use, Shakespeare says New England Ropes introduced a new 11.5mm rope within the last couple of years, called Tachyon, for climbing. (The name is derived from quantum physics and refers to a theory of the fastest and lightest.) This rope is a double-braid with a third part, an inner core. He says the rope stays rounder and firmer regardless of use and remains s pliceable, permitting spliced eyes in one or both ends of the line using a double-braid splice. Sold into the professional arborist market, this rope is popular with competitive climbers because it is fast to use and strong.
The 11mm-class rope is seen as more high performance and “cutting edge,” says Shakespeare, although it’s essentially the same as half-inch rope. The difference lies in ease of use and speed. “If you’re lugging, packing and unpacking 150 feet of rope, a few pounds make a difference during the day,” he adds, adding that a thinner rope may have a shorter life than the standard half inch due to less material being used, but a lot of that depends on how the rope is used and cared for.
“We are finding that, in this economy, people do try to stretch the budget, and that sometimes includes delaying rope purchases,” he says. But people need to be aware of how much material has been lost to wear, Shakespeare says, and to check for nicks and how many fibers are actually broken.
Jim Cass, Northeast regional sales manager for Samson, says, “Cuts are the biggest problem. Technically, a rope can last forever if you keep it clean. Dirt inside between the braids and fibers will cut a rope over time.”
There are numerous rope constructions, but probably the most popular overall is the 16-strand, and for climbing, a polyester 16-strand, which Samson features with a stabilized nylon core. “We use nyl on to prevent “milking,” when the core can come out of rope on its own. Our process eliminates that.”
“Popularity is drifting toward lighter ropes,” he says, “which are easier to use for smaller hand sizes. That explains the interest in 7/16-inch and 11mm, 24-strand construction polyester rope.” A half-inch rope will feature an 8,100-pound break strength versus 6,000 pounds on a 7/16-inch, exceeding the ANSI standard of 5,400 pounds. “We aim to produce all our rope with at least a 10 percent buffer above minimum standards,” Cass says.
“About 90 percent of purchase decisions come down to feel. Some people like small ropes, others with large hands like the larger half-inch or even what we call a beefy half-inch, which is slightly larger. Whatever a climber is weaned on, it’s difficult to get him or her to switch to another because they’ve gotten secure with the rope’s feel. Feel is why women and smaller climbers like more of the 11 or 11.5mm lightweight ropes and why competition climbers insist on lightweight rope; speed is of the essence.”
Regarding wear and tear, Cass points out that if you cut only one of the 16 strands in a rope, you’ve lost a sixteenth, or more than 6 percent, of a rope’s capability over its entire length. His opinion? “Basically if you cut strands, retire the rop e. It’s your lifeline. Don’t mess with your lifeline. People may switch the rope to a lowering line to drop light loads. If an 8,100-pound rated rope loses a sixteenth of its capability, it may still be strong enough to lower limbs.” (Just be sure to clearly mark that the rope is not for climbing!)
We asked Jamie Goddard, East Coast sales manager for Yale Cordage, about rope construction. “Twelve-strand is more or less commercial grade; a standard, economical single-braid construction eliminating the core with a nice nubby feel commonly preferred by climbers because of the hand feel and not used as much with mechanical hardware.
“Sixteen-strand is most common and considered professional grade. It has a smoother cover than 12-strand and runs well through cam devices. Our XTC 16-strand is known to have the tightest cover in the industry to keep out contaminants, and features a nice tight over-braid.”
“A 24-strand is considered our competition grade for competitive climbers. It features the smoothest cover and lowest elongation, resulting in minimal bounce and getting to top quicker. Typically,” Goddard says, “a 24-strand refers to smaller diameter rope, less than a half inch, in the 11 to 11.7mm range. These are more favorable to recreational climbers because of their light weight,” he adds.
According to Goddard, however, the half-inch, 16-strand, 6,200-pound rated rope is pretty much the tree care standard.
With regard to retiring rope, if more than two adjacent strands are cut, “throw out that rope immediately!” warns Goddard. He recommends cutting an unsuitable rope into unusable pieces to avoid reclamation by and possible future liability from, “dumpster divers.”
“Some will downgrade a climbing rope to a lowering line, but my thinking is that if the rope is not good enough to hold you at, say 250 pounds, what will you do if the shock load exceeds the capacity of the damaged rope,” Goddard says. “The way I see it is, you buy a rope for a purpose. When its life is over for that purpose, it’s over. Period.”
You can help prolong your rope by taking care of it, Goddard says, and that includes keeping it clean. Wash it! He recommends no abrasive detergents, but rather a petroleum-based cleanser. Wash, rinse thoroughly and let air dry – without using heat or sunlight. Both heat and UV light will attack rope.
Another tip. Use both ends! By utilizing both ends of a rope, you get even and longer wear.
Regardless of its diameter or construction, rope is not to be taken lightly, whether you’re using it for climbing, rigging or lowering. One bad decision can bring down you, your material and even your business. Consider rope to be a serious tool that can make you or, literally, break you.
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