Proflex M42 bimetal band saw blade
The Proflex M42 bimetal band saw blade has teeth that are designed to effectively cut structural steel workpieces.
Teeth Set On Edge
A bimetal band saw blade has a tooth design to effectively cut structural products
By Alan Richter

hen cutting steel profiles and girders for construction applications, end users will usually seek a band saw blade that keeps its teeth intact, minimizes burr formation and is less susceptible to vibration. Mike Masters, chief technology officer for WIKUS Saw Technology Corp. in Addison, Illinois, says the company’s Proflex M42 bimetal blade does all of that. The M42 grade of high-speed steel for the blade has a flexible alloy backing to slow material fatigue.

Although it is a universal band saw blade, the Proflex’s tooth design makes it optimal for sawing structural steel workpieces, which require overcoming the challenges of sawing with an interrupted cutting channel. For example, Masters says, when cutting a pipe, the saw blade initially moves into solid metal in which the blade is fully supported and the teeth are spread over a large section of the pipe. Soon, however, the blade passes through solid metal and starts cutting two walls separated by space. “Now you are supported by two small sections and it creates a lot of vibration,” Masters says.

Proflex blade’s tooth design
The Proflex blade’s tooth design features a duplex relief angle.
Fighting vibration
In addition, when cutting a bundle of tubes, for example, the tubes can move around because they aren’t as tightly secured as plate or bars would be, according to Masters. As a result, the blade sometimes grabs a tube and causes it to spin or lift up during the cut and jams it into the blade’s teeth. “There is always a piece that’s loose,” he says.

The Proflex blade’s tooth design features a duplex relief angle instead of a single relief angle. “If there is vibration and movement of materials to cause the teeth to chip, it’s designed so that the rest of the teeth don’t strip right off the blade.”

Using coolant with the correct concentration
Using coolant with the correct concentration is critical for successful sawing.
The design creates a landing and supports the blade from dropping down into the rest of the work to help reduce tooth strippage while sawing bundles, I-beams and profiles, he adds. “There’s a lot more vibration during that type of cutting than when cutting a solid material because the solid material dampens all that vibration,” he explains.

Some of the vibration created when sawing workpieces with an interrupted cutting channel can be reduced by having a machine with side clamping to squeeze both sides of a bundle and a top clamp that presses down, Masters says. Some sawing operators tack-weld the ends of parts together so they can’t spin during the cut or use steel strapping to tightly secure a bundle, but those methods add time and labor.

Heat and vibration are what kill that cutting tool.
mike masters, wikus saw technology
To reduce burr formation when a blade exits the cut, the Profile tooth design also enables the blade to shear off the last chip instead of having it hang and break off, Masters says. That capability is particularly beneficial for manufacturers that saw pipes and then thread them to enable coupling the pipes together for oil drilling applications. “The less burr they have, the less work they have to do to clean up the edge of that coupling to do the next operation of putting the threads in.”

When the wall of a workpiece material is less than ¼-in. thick, Masters says a blade with a positive rake angle tends to shave and lift chips, snagging and pulling on the thin walls and distorting the workpiece. “That’s what is going to jam it into the blade and start stripping teeth.” For those applications, he recommends a blade with a 0-degree rake angle.

Protective coating
In addition to the standard Proflex M42 band saw blade, the blade manufacturer offers additional Proflex versions. One is the Proflex Premium M42 in which the teeth have a titanium nitride coating to extend blade life. According to Masters, the coated blade can run 10 percent faster than the company’s recommended cutting speeds for uncoated blades.

WIKUS also offers the Proflex SW M42 blade. SW stands for “set wide,” meaning the teeth are set a little wider than the other models to create a wider kerf and reduce the risk of the workpiece material pinching the blade and causing it to seize during the cut, Masters explains. “Whether it’s cutting tubes or channels or angles, you’ve got what people refer to as a pinching issue because there is residual stress in those plus the movement of the part.”

That problem is compounded when sawing large I-beams and the tables on the machine are not exactly level, he adds. “When you break through that web of material, that I-beam starts to pinch together because there is a lot of residual stress because of the way I-beams are processed.”

interrupted cutting channel
Proflex’s tooth design overcomes the challenges of sawing with an interrupted cutting channel.
Similar to other Premium blades from WIKUS, the Proflex Premium SW M42 blade is coated with titanium nitride.

Masters says the Proflex blades are suitable for use on any type of band saw, and customers frequently saw parts that aren’t structural metals, but the majority of applications use flood coolant to lubricate and cool the blade/workpiece interface. “Heat and vibration are what kill that cutting tool.”

Structural workpieces
Structural workpieces were cut with a Proflex band saw blade.
In addition to providing an adequate coolant to keep the amount of heat in check, having the correct coolant concentration is critical to successful sawing. Depending on the type of coolant, Masters says the recommended coolant concentration is from 15 to 20 percent, whether it is a synthetic or water-soluble coolant.

When all the sawing components are in order, Masters says the tooth design of the Proflex blade makes it well-suited for sawing structural workpieces. “It’s a real workhorse.”

WIKUS Saw Technology Corp., Addison, Illinois, 800/369-0447,