Above: Doringer offers in-house sharpening services and claims that blades resharpened on its automatic machines can perform just as well—if not better—than brand-new blades. Photo: Quantum

Achieve straight, accurate parts free of burrs and discoloration

April 2019 - Often, the first step in a manufacturing process is to make a cut that transforms a long aluminum bar or wide steel sheet to a usable size. Operations that require accurate cuts straight off their sawing equipment frequently turn to cold saws. Cold saws provide square, burr-free cuts with a smooth, milled-like finish for both cut-to-length parts and miter joints. They typically run at a lower rpm than a chop saw or band saw but will cut material more quickly. A 6-in.-by-2-in. channel iron can be cut in under 8 seconds, a 1-in.-diameter, 16-gauge tube in 2 seconds and a 3-in. schedule 40 pipe in under 3 seconds.

“The secret to cold saws is in the gearbox,” says Bill Bailey, president of Doringer Cold Saws. “We have a 31-to-1 gear reduction. The motor comes in at 1,700 rpm and then reduces to 54 rpm. That gives you the torque you need to saw through the steel.”

The ability to cut efficiently at lower rpms also makes the saws safer because there’s no heat, sparks or dust, and very little noise. Cold saws also use a blade that can be resharpened up to 50 times, reducing steel cutting costs by 90 percent.

“With schedule 40 standard 2-in. pipe, you will probably get 1,800 to 2,000 cuts per sharpening, and then you can get between 20 and 25 resharpenings out of a saw blade,” Bailey says.

The D-350 SA model is engineered for precise, repetitious cutting of solids, large pipes and wide sectionals.

Made in California

Doringer began manufacturing cold saws in 1991, and the company offers three models: the D-300 12-in. manual cold saw, the D-350 14-in. manual cold saw and the D-350 SA 14-in. semiautomatic cold saw. All three machines are suitable for cutting steel, stainless steel and aluminum, and the D-350s can handle larger material, including pipes, solids and wide sectionals.

Doringer does all the product design, quality control, machining, assembly, final testing and inspection at its 48,000-square-foot facility in Gardena, California. It also offers one-day turnaround blade resharpening services using modern, automatic equipment—a Loroch Evolution K850-M CNC and three Tempo ECE 45 CNC sharpening machines.

The company stands behind the performance of its saws, and Bailey highlights some of the key features of the equipment, including its pivot point (where the saw head pivots to cut through the steel), which is “low down near the table, right next to the material. Because the pivot point is equal vertically to the material being sawed, there’s less vibration; less chattering; a cleaner, more accurate saw cut; and much longer blade life.”

Instead of a just a vise for holding material, the saws also have a large, 240-square-inch miter table, which allows for special clamping and enables cuts of greater than 45 degrees.

Because Doringer builds all its machines in California, the company is capable of fulfilling custom requests. Bailey says one of the most common customizations is turning a D-350 SA semiautomatic saw into a double miter saw.

“We’ve had a dozen or so customers that have wanted us to take the two semiautomatic saw heads and put them on Thomson rails so they can slide either saw or both saws to a particular dimension of cutting. We’ve sold this model to frame manufacturers, a company that makes axles for golf carts—anybody that wants to cut two edges on one piece at the same time.”

Customers also can choose to make their D-350 SA semiautomatic model fully automatic by adding a material positioning system from Doringer’s Vancouver, Washington-based partner, TigerStop. “The operator programs in the desired number of pieces and cut length. Then, the TigerStop feeds the material, the saw comes down, clamps the material, cuts it, and the saw head goes back up and the material is again fed to the desired length,” Bailey says.

Doringer is capable of manufacturing custom saws, including double-miter configurations.

Keep on cutting

Beyond equipment, Doringer’s experience makes it a trusted resource on cold sawing best practices and maintenance. When cold sawing, it’s important to let the saw do the work, not pull down too hard on the handle, and ensure the material is tightly held in the vise. When sawing stainless steel, the company suggests cutting at the lowest available speed, using the smallest diameter sawblade and enriched coolant. Nonferrous materials, on the other hand, require the highest available speed, using the largest diameter available in sawblades.

“We have owner’s manuals and instructional videos showing simple cuts,” Bailey says. “Let’s say a customer is cutting 1-in. by 4.-in. solid steel in a straight cut. We emphasize that if you stand the workpiece up so that you are cutting through the 1-in. length, it’s much faster.”

Being able to cut efficiently means the line keeps humming. “If the saw is down, you’re not cutting steel,” Bailey says, and the welders, assemblers and painters down the line aren’t working. “We are American-made, and we are the factory, which allows us to guarantee that replacement parts will always be in stock and we can ship them out the same day. We know how important the saw is to a manufacturer.” FFJ