Raising the bar: new tools ease the pain of bending, cutting, and tying rebar

Tools of the Trade, Sept-Oct, 2003 by William D. Palmer, Jr.

Those tough guys who spend their days cutting, bending, and positioning rebar aren't called "rodbusters" for nothing. Using a hickey to make 90-degree bends, crouching over tying wire with a spring-return tying tool, and cutting bars with a torch or cut-off saw--it's hard physical labor. But the newest power rebar tools are making the life of the rodbuster, and anyone else who has to configure and place concrete reinforcing steel, safer and much less taxing.

While the large bending and cutting machines used in fabricating shops have long been available, some of the newer tools are smaller and lighter in weight, making them easy to transport to the field. Some can even be used on embedded bars. Both corded and cordless benders, cutters, and combination benders/cutters are now light enough to carry around all day.

Selecting Rebar Tools

To decide what type of tools you might need for reinforcing steel and if you should buy them, answer a few simple questions:

* What size bars will you be working with? Bigger bars require larger, less portable equipment. "If you only need to cut and bend #8s occasionally," says Fascut's Frank Olah, "get the smaller, less cumbersome equipment."

* How much steel are you placing? The more rebar bending and cutting you do, the better--and faster--you'll want the equipment to be. Many bench cutters and benders that can handle larger bars also can cut or bend several smaller bars at once, speeding up production.

* Do you want separate tools for cutting and bending or a combination tool? Combination tools are typically heavier for a given bar capacity than tools that cut or bend only. Combination tools for bar sizes greater than #5 are normally bench units that weigh more than 100 pounds. "A #5 is about the largest bar you can bend and cut by hand," says Benner-Nawman's Mel Kientz. "Beyond that you'll need some sort of power tools."

* How many and what size will you cut? Rebar has traditionally been cut on site with a torch or cut-off saw--or even bolt cutters. But each of these techniques actually changes the molecular structure of the steel. The best tools, cutters that use square blocks as jaws, actually shear or break the bar, leaving the strength of the bars unaltered. Some of these cutters can be used easily on bars as large as #10, even with Grade 60 steel. (The bar size number of reinforcing steel refers to the number of eighths of an inch in diameter so that a #6 bar is 6/8 (or 3/4) inch in diameter. The grade of steel relates to its specified minimum yield strength used in design so that a Grade 60 steel has a specified yield strength in tension of 60,000 pounds per square inch.) Most cutting tools have cutting blocks that rotate so that they can be changed to a new edge eight times before replacement.

* Are the tools you're considering really up for the job? "Some manufacturers will say that their benders and cutters will work with #6 bars," notes Brad Rozema of EZE Bend, "but make sure they can consistently cut or bend Grade 60 steel." Grade 40 is typical for residential construction while Grade 60 is more common on commercial jobs.

* Do you want corded or cordless tools? "Cordless tools are a niche market," says Olah. "It's not a do-all piece of equipment, but if you're in a place where it's hard to get power, the cordless units are great. We've sold a lot of cordless units to the New York City Fire Department that uses them to cut the security bars off windows in the city. A bunch of them were used during the World Trade Center rescue."

* Do you really need portable handheld tools? Most handheld tools are cutters only and many benders and cutters (even those that are called "portable") are quite heavy--as much as 400 pounds. The models in the 200-pound range often come with handles for setup on the jobsite, or they can be moved with a loader or mounted onto a trailer that is often also set up to transport steel to the job. Larger machines can bend precisely to a pre-set bend angle and are better for bending longer bars since they use a rotary table bending system where only one end of the bar moves during the bending operation. Portable handheld tools, on the other hand, "open doors that were not open in the past," says Rozema, "since their portability allows bending right on the spot and also of pre-embedded bars. This dramatically reduces the materials needed, since it's easier to bend bars [than it is to use] mechanical couplers or splice-in short bent sections."

Manufacturers

Here's a roundup of offerings from the different manufacturers of bending and cutting tools.

Benner-Nawman: Benner-Nawman carries the industry's most extensive line of bending and cutting tools. Most tools are electric/ hydraulic, using hydraulic power to actually drive the cutting heads. "The electric/hydraulic system keeps the power requirements to 12 amps," says Benner-Nawman's Mel Kientz. B-N's tools are simple, easily serviceable, and reliable. They carry both corded and cordless handheld cutters, and bench-mounted benders.