Tech Rescue

Cutting Advanced Steel

Issue 3 and Volume 10.

Advanced steels allow automobile manufacturers to meet federal motor vehicle safety and emissions standards and increase fuel efficiency for the consumer. Another solution to myriad safety standards is the addition of multiple layers and thickness of material in key areas, which presents challenges. Advanced steels were initially used in limited areas by only a few manufacturers, but they have become much more prevalent in most makes and models of motor vehicles over the past several years. Although this construction design increases crashworthiness and protects occupants in a variety of collisions, it also provides challenges to responders, including the ability of rescue tools to effectively make a substantial opening in the immediate area of the patient. Typical evolutions such as bravo post removals and roof removals may be virtually impossible with hydraulic, electric, and pneumatic tools that have been sufficient for many years.

Necessary Tools

Many departments’ answer to advanced steel is the purchase of new-age cutters that boast cutting forces in excess of 200,000 pounds. Several scenarios exist where responding units may not have this capability to mitigate advanced steel.

  •  Departments may have outlying companies that use combination tools until a more dedicated rescue vehicle with extended response times can arrive. A comparison of different manufacturers’ combination tools shows a maximum cutting force of 120,000 pounds, far less than needed forces.
  •  Some departments cannot afford newer cutters and systems, given other priorities and budget constraints. Tools purchased just two or three years ago may not be able to meet demands, and administration cannot justify the redundant expenditure.
  •  The hydraulic cutters may not be readily available because they are being used elsewhere at the motor vehicle collision for the completion of necessary tactics. These tactics may be taking place on the same vehicle or other vehicles involved in the collision.

Responders have searched for a solution to this problem for several years and have tested a variety of tools including reciprocating saws, rotary saws, air chisels, and hand tools. Realistically, reciprocating saws could provide the most suitable option, but the weak link has consistently been the blades. Blades from multiple manufacturers have been tested with a wide range of teeth per inch, width and height specifications, designed cutting applications, blade coatings, etc. Cooling liquids and gels have even been placed on blades to reduce the associated heat. However, no blades have been any more successful than basically scratching the surface before completely destroying the teeth.

Metal Cutting

At the Specialty Tools and Fasteners Distributors Association Annual Convention and Trade Show in Charlotte, North Carolina, Diablo introduced the Steel Demon carbide-tipped reciprocating blades for thick metal cutting. Diablo has been well known for its premium brand of cutting tools and abrasives specifically designed for the contractor and remodeler to provide superior performance while withstanding the most extreme conditions. However, with this innovative blade design, Diablo was able to appeal to responders and provide a cost-effective solution to the lack of ability to cut advanced steel.

The Diablo Steel Demon carbide-tipped reciprocating blades are the first carbide-tipped blades designed for extreme metal cutting, including high-strength alloys, cast iron, and stainless steel. They are currently available in six- and nine-inch lengths with eight teeth per inch. The high-performance carbide allows for greater durability and cutting performance in thick metal, and the enhanced carbide tip-to-blade connection provides extreme impact resistance. The blade also features an oversized blade body for straighter cuts with less vibration and a Perma-SHIELD nonstick coating for less heat and friction.

At approximately $10 to $15 retail price, this blade is comparable to other special application blades and, when considering the efficiency it provides, a reasonable option in comparison to multiple standard bimetal blades. If cost is an issue, it may be appropriate to have several bimetal blades for standard applications and several of these blades for advanced steels or thick metals.

Responder Advantages

The Steel Demon carbide-tipped reciprocating blade provides two decisive advantages for responders at motor vehicle collisions. First, it provides another option for cutting advanced steels. In situations described above and other limited-access or ergonomically poor positions, reciprocating saws with this blade may be the primary tool of choice when encountering advanced steels. Second, it provides increased cutting capacity and longevity vs. bimetal blades. The carbide-tipped blade delivers 20 times longer cutting life than standard bimetal blades in extreme thick metal cutting applications between 3⁄16 inch and ½ inch.

The benefits of the Diablo Steel Demon carbide-tipped reciprocating blades are not limited to motor vehicle collisions. Reciprocating saws are considered a standard forcible entry tool and, in some cases, a ventilation tool. Advanced steels are being placed in some padlocks to deter the use of simple hand tools by burglars. In addition, most situations that require forcible entry include the use of thick metals that quickly destroy the teeth of bimetal blades, which is one reason a cordless reciprocating saw that is quickly and easily deployable may not be selected.

Because this blade has some different characteristics than bimetal blades, there are some subtle differences in operation. As with any other new tool responders should understand the difference and train accordingly. After several training sessions and discussions with the manufacturer, I found several tips that will increase the proficiency and longevity of the blade.

The optimum reciprocating saw speed is approximately 2,000 strokes per minute, which reflects about 75 to 80 percent of the maximum speed of most reciprocating saws on the market. Reciprocating saws so equipped should be placed in the orbital setting. When possible, avoid beginning cuts on a thin surface such as a riveted or welded seam. Attempt to start the cut on larger, flatter surfaces and work into those thinner areas.

Changing Response

As manufacturing technologies and applications increase, responders are more likely to encounter advanced steels during extrication incidents and other specific applications. Hydraulic cutters will continue to be the most prevalent option to sever these parts, but now there is another option in the form of a reciprocating saw with a carbide-tipped heavy metal cutting blade.