Cool Tools: Conduit Benders
Published: April 2010
Hand conduit benders fall into a category of hand tools that are so basic it may be simple to miss the improvements that make them easier to use, more durable and more productive than older products.
The hand bender’s function is the same as always, and today’s tools may look much like the Benfield and Gardner benders that have been used for decades. However, today’s hand bender products are significantly better than those sold only two or three years ago.
“Recent improvements in hand benders have features that make the product more durable as well as easier and more accurate to use,” said Christian Coulis, product manager, Gardner Bender (www.gardnerbender.com). “These features include wider foot pedals to increase control, better embossing of bend angles to make accurate bends easy, and more durable components to increase the life of the product.”
Coulis said Gardner Bender’s new Big Ben line of heat-treated aluminum benders has improved traditional bender designs by enlarging the hook, increasing foot pedal clearance and pedal size by 40 percent, making markings more visible, and incorporating a dual sight-line system to facilitate making bends on the floor or in the air. A bend-back channel easily corrects conduit over-bends.
Klein Tools (www.kleintools.com) recently introduced the new Aerohead line of hand benders with the bender head made of an aerospace-grade alloy.
Benfield or Gardner?
For years, hand conduit benders have employed either Benfield or Gardner heads with electricians often holding strong preferences for which they prefer to use. Benfield models are made of iron, and markings on the heads serve as reference points for bend angles. Gardner-style models are made of die-cast aluminum, and they incorporate built-in spirit levels at the 45-degree and 90-degree positions to assist in making accurate bends.
Vince Kendzierski, Klein product manager, said the alloy is manufactured using an advanced process to produce a bending head that is up to 50 percent stronger and lighter in weight than ductile iron.
“Electricians no longer have to choose between the perceived strength of cast iron or the lightweight properties found in other benders,” he said. “Aerohead provides the best of both worlds.”
The Aerohead’s Benfield head has well-defined, cast-in benchmark symbols with an arrow that points to the beginning of a bend, a star that indicates back-of-bend locations and the teardrop symbol, which indicates the exact center of a 45-degree bend. Degree and multiplier scales are cast into the head as are a series of alignment points on the hook end to help line up conduit and make straighter bends. Handles are made of high-strength steel and swaged at the end for inserting conduit and correcting over-bends.
The Hoppy Bender from Rack-a-Tiers (www.rack-a-tiers.com) is set apart from other benders by a patented locking swing stop mechanism to help make exact and repeatable bends, and it helps inexperienced workers create offsets and 90-degree bends.
Reference charts for locating bend marks are printed on the handle. Multipliers or numbers and markings are permanently etched in the ductile iron head to know where to position the stop. Standard 221/2- and 45-degree markers are engraved for commonly used bends. Hoppy Benders are available for 1/2- and 3/4-inch EMT.
Greenlee (www.greenlee.com) offers a new generation of hand benders with enhancements, said Ron Axon, senior product manager. They include enlarged foot pedals and increased toe room to ensure greater control, stability and leverage; crisper markings and coloration to maximize visibility on low-light job sites; and larger, straight handles for grip comfort and consistency.
Bending PVC Conduit
“PVC conduit usage is growing some since the cost of steel has gone up in recent years,” said Ron Axon, Greenlee senior product manager. “PVC is becoming more common as a conduit in below ground or in poured floors while metal conduit is the most common for above-floor or exposed conduits due to its durability and impact strength. Commercial construction is one of the largest users of PVC conduit.”
Christian Coulis, Gardner Bender product manager, said use of PVC also is increasing for landscaping and outdoor-living power applications.
The most common method of bending PVC pipe is with the use of heat—either with a electric heat box or blanket with heating elements, although mechanical cold-bending devices also are available. Bends are made using wood forms or other round objects depending on the bend radius desired/required, Axon said.
Specialty manufacturer HotBend (www.hotbend.com) markets a hand-held heat gun using propane. Co-owner Christ Weggeland said the device can bend sizes of PVC up to 8 inches in diameter.
“Our product has the ability to go to where the bends are needed,” Weggeland said. “And because it isn’t an oven in which pipe is placed, it can reheat and rebend already-bent pipe. Finally, there is no warm-up time like there is with electric ovens. When the trigger is pulled, there is an instant blast of hot air of 125 BTU at 100 mph. The time savings that results from the use of the HotBend tool make it stand alone.”
Rack-a-Tiers (www.rack-a-tiers.com) offers an alternative to heating methods for bending PVC. The Pipe Viper is a spring device inserted in the PVC conduit to maintain internal diameter while making cold bends. It is promoted as being faster and easier than cutting pipe and gluing fittings.
“The power-pedal feature is on both aluminum and iron bender heads for 11/4-inch EMT bending,” Axon said. “A complete set of markings speeds bending in head-up or head-down orientations, and our patented sighting system provides an easier and clearer line of sight for accurate bend angles during head-down bending.”
Axon compares the skill of using a hand bender to a highly developed art form that professional electricians take great pride in doing well.
“Mastering the use of conduit bending tools separates experienced journeymen electricians from apprentices or the occasional bender user,” Axon said. “Consistently making good, wrinkle-free, and round-shaped bends that result in parallel or concentric conduit runs not only ensures good results for cable pulling, but are an aesthetically pleasing outcome as well.”
Large jobs have bending requirements beyond the capabilities of basic hand benders, and several options are available to fit workloads.
When bending workloads require more than a hand bender, mechanical benders are a step up. While muscle power still provides the force of making bends, shoe and bending components are mounted on a cart or carriage that can be rolled around the job site. Interchangeable shoes are used for various conduit types and sizes. Some models can be removed from the cart and mounted on a truck or workbench.
High-production bending requires electric models, which speed production by making bends in seconds. They have programmable capabilities for making accurate repeat bends at the same angles, remote pendant controls, and the capability to calculate layout measurements for various bends before work begins.
“Electrical benders have evolved greatly in recent years,” said Gardner Bender’s Coulis. “Some of the major improvements involve making the product easier, faster and safer to get to and throughout the job site. Other newer features simplify the ability to preset the bend angle. This process helps immensely in making fast, repetitive, accurate bends, especially in an offset bending application.”
Although some higher end benders allow multiple types of conduit to be bent with a minimal number of parts, Coulis said bending different types of conduit—EMT, IMC, rigid, PVC-coated rigid and electrical PVC—often requires several different components within a bending machine. As outside diameters of conduit changes with the type of conduit being used, dimensions and shape of the bending shoes must be different, too, as must the roller supports that form the outside edge of the bend radius.
Hydraulic benders are most often used for rigid conduit or for conduits in sizes from 21/2 to 5 inches, which are too large for electric benders. They make smooth, round bends without conduit squeeze or bulge and without splitting pipe seams. Manual or electric hydraulic pumps provide power.
Greenlee and Gardner Bender both offer a complete line of benders and accessories from hand, mechanical, hydraulic, sophisticated electric models, and equipment to bend PVC pipe (see box).
“Contractors require a variety of conduit bending tool solutions to complete their jobs safely, efficiently and professionally,” Axon said. “With the growth in lean construction practices, contractors are increasingly utilizing prefab shops to complete conduit bending work at their facility and then bring the bent conduit to the job site for installation. The range of bending tools available give the contractor the ability to really choose the right bender solution for a given job and complete their work faster, safer and easier.”
GRIFFIN, a construction and tools writer from Oklahoma City, can be reached at firstname.lastname@example.org.