Cool Tools: Fish Tapes
Published: February 2010
From a length of stiff wire pushed through a pipe to a precision instrument for running wire through conduit and many other confined, difficult-to-access spaces, the evolution of the fish tape illustrates how a relatively simple basic tools advance to meet changing needs.
The unknown electrician who first pushed a rigid length of wire through a pipe to pull electric wire back through it had a good idea but probably didn’t profit from his common-sense invention. The first fish tape tools, consisting of pulling wire enclosed in a case, were introduced more than 50 years ago.
“Fish tapes today come in many different cross-section profiles and materials to ease fishing in conduit, walls, under carpets, subfloors and above suspended ceilings, as well as around other obstacles,” said Ron Axon, Greenlee Textron.
The most widely used tapes are made of steel and fiberglass and are available in lengths from 25 to 250 feet. Rugged cases have an inner rotating reel on which tape is wound. An important element of the tool’s design is how smoothly tape pays out and is retrieved without kinking or tangling. Retainers keep tape properly positioned at the opening to reduce the risk of breaking. As with most other hand tools, ergonomics is an important design consideration, especially handle design and how it positions the user’s wrist.
New Klein Tools Fish Tape
Klein Tools has introduced Depth Finder steel fish tapes with laser-etched markings in 1-foot increments. Markings are numbered in descending order so the user knows how much tape remains in the reel and can quickly calculate the length of a conduit run. Because markings are etched in, they can’t wear off. Vince Kendzierski, product manager, said other fish tape improvements include making 13-inch diameter cases standard on larger models, permitting a larger spool, which enables the tape to wind 15 percent more per revolution than on a standard 12-inch size. Ergonomic finger grooves provide additional leverage, and the handle is shaped to facilitate fast unwinding and rewinding. —J.G.
Useful accessories include tape leaders, multiwire pulling leaders, swivel balls to prevent wires from twisting during pulling, kits with new eyelets and crimping tools to attach eyelets to tape, and carrying cases.
Wire-pulling lubricant reduces the friction in cable pulling over long tough runs and can be essential to successful pulls. It is important to use a lubricant that is compatible with the cable type being installed.
Representatives of three leading manufacturers provide information on the current line of fish tapes.
Gardner Bender, Christian Coulis, product manager, said: “Fish tapes typically used by electricians range from 25 to 250 feet in length and are made of steel, stainless steel or fiberglass wire. Many manufacturers offer multiple styles of fish tape housings as well, with a premium line focused heavily on durability and ergonomics.
“Most fish tapes can be used for multiple applications; however, many electricians carry several types of fish tapes and leaders to meet the specific needs of pulls on a job site. Tape with a flat tip or leader is preferred for fishing cable underneath carpet. A very rigid fish tape or fish stick is preferred for fishing over suspended ceilings. Fiberglass fish tape is a necessity when pulling close to live wire where electrocution is a concern. The type of application, user preference and the safety needs of a particular pull are all factors that influence what type of fish tape to use.
“Housing design and durability, tape length, width and weight, tip design and overall flexibility of the tape are all features that are weighed during the decision-making process.
“Leaders are a great accessory that can make a fish tape more useful. With the use of the proper leader, tape can be fed through conduit or tight spaces more easily and more efficiently.
“There has been an increase in the use of fish sticks and fish poles. The demand for cable has grown in residential and commercial construction. Fish poles are used in applications where support and an extended reach is necessary, such as over acoustical ceilings, up walls, under subfloors, and [into] other small areas that are difficult to reach.
“Electricians are installing more data, power, security and multimedia cable, and these products help make the installations efficiently and professionally,” Coulis said.
Different Types of Fish Tapes
Steel fish tapes are preferred by most professionals because of their excellent pushing characteristics. Good column strength allows long runs before the tape begins to kink. Because steel tapes are flat, it can be difficult to turn through elbows, and because they conduct electricity, they are a safety hazard when working near live circuits. In these situations, tape of a nonconductive material should be used.
Stainless steel tapes offer the same benefits of steel types with the added advantage that they don’t rust and are ideal for working or storing in wet, damp conditions. However, resistance to corrosion comes with a price: stainless steel costs more than steel.
Fiberglass tapes are round, which provides easier pushing through conduits with bends and turns, and they are nonconductive for working in spaces near energized circuits.
Tapes made of “S” structural grade fiberglass are preferred to tools of “E” economy grade material. S-grade fiberglass tapes accommodate tighter elbows and box transitions than the less-expensive material.
Stranded steel tape is made of strands tightly woven into a highly flexible wire. It is used for pushing through multiple bends and can be used as a leader on steel and stainless steel to make them easier to get through bends difficult for flat tape.
Nylon tapes are not recommended for professional use. Nylon has low column strength, which limits pushing capabilities and has low tensile strength for pulling back wire. Stored coiled in its case, nylon resists flattening when it is unwound from the coil, which also complicates pushing. —J.G.
Greenlee Textron, Ron Axon, senior product manager, said: “Installers require a variety of fishing tools to complete their jobs safely, efficiently and professionally. A variety of factors influence the selection of a tape for a given job, including individual preference, cost, distance, work area space, stiffness, “fishability,” corrosion resistance, fishing-media cleanliness and dielectric properties when in proximity to live circuits.
“Grip comfort, tape length, tape weight, tape-tip design, ease of paying out the tape and ease of rewinding the tape are all important considerations when choosing a fish tape.
“Fish tape case and handle ergonomics have been improved to increase user productivity by speeding pay out and rewind actions, reducing fatigue during use and increasing tool life. There are several different tape leaders that can be attached to the end of tapes to help with fishing and/or pulling jobs.
“With the growth in demand for more power, data, audio, video, security, alarm and energy-control installations, the expanded variety of fishing tools are necessary to complete this work, especially in existing construction. Telescoping poles and/or threaded rods are very useful above suspended ceilings, below subfloors, in crawl spaces and other places where a tape may be difficult to navigate. They are also very useful when fishing for short distances or when trying to route a wire in an area where a person cannot fit. The popularity of reacher-fishing has grown significantly with the expanded choices of telescoping poles and threaded rods and tip accessories available to choose from, including luminescent rods for dark spaces.
“The choices of fishing tools available today give electricians the ability to select fishing tools—both tapes and reacher fishing tools—to be prepared for any situation that arises on a job.” Axon said.
Klein Tools, Vince Kendzierski, product manager, said: “Consider the job at hand when selecting the tool to make a fish run. Length of run, amount of bends, the amount of wire already present in the conduit run and electrical environment all impact the type of tape to use.
“Flat steel is flexible to navigate 90-degree bends, yet rigid enough to add muscle for pulling and pushing through tight spots. ‘Navigational’ tapes such as fiberglass, nylon or spiral-wound wire are lightweight and manage multiple bends easily but sacrifice the pull strength and rigidity of steel.
“Case and handle durability are important factors when selecting a fish tape. Quite often, the case remains on the ground during pulls and is openly exposed to the rough treatment of the job site. As this product goes through this exercise maybe a dozen or so times a day, solid body construction with the right materials is critical.
“For professionals, a fish tape can be a moderately expensive investment, and there are products available such as replacement tips and tip kits that extend the use life of both metallic and nonmetallic tapes.
“Fish poles offer a more precise way to run wire for short runs and also allow you to guide wire over obstructions. Because they are rigid, flexible and extendable, poles offer more control of the tip for exact placement,” Kendzierski said.
GRIFFIN, a construction and tools writer from Oklahoma City, can be reached at firstname.lastname@example.org.