Sawing exotic materials, such as high-temperature superalloys, as well as hardened materials, can prove problematic. “You can eat teeth for lunch on that bandsaw blade trying to cut them,” said Curtis Reichhold. He’s president of Electrical Discharge Saws Inc., a supplier of electrical discharge saws that is working on commercializing an attachment for a manual lathe that turns the machine into an EDS.
Instead of buying a dedicated EDS, which costs about $225,000, the EDS attachment will sell for considerably less, according to Reichhold. “The majority of job shops have a manual lathe they can take and make it a superhardened- or exotic-material slicer,” he said, noting, however, that the company has to analyze each application with a customer before proceeding.
The attachment bolts onto a lathe’s ways and erodes electrically conductive material with a rotating ¾ "-high × 0.032 "-thick blade while the workpiece rotates as well. “Because of the expense of exotic materials, we try to keep blade thickness to a minimum,” he said, noting this minimizes waste.
Reichhold emphasized that the EDS blade cuts cleanly, produces a heat-affected zone of only about 0.002 " deep and doesn’t workharden the material.
When a shop doesn’t need to use the EDS, the attachment remains on the lathe, which can still function as a conventional machine tool. Between uses, however, an end user must wash the dielectric fluid, which is caustic, from the lathe to avoid causing damage, primarily to the ways.
Unlike an EDS that can cut a workpiece material with virtually any shape, the attachment is only for cutting round bars. In addition, the attachment is suitable only for manual lathes to avoid a variety of issues, such as coordinating the lathe speed and blade speed and the need for a feed mechanism. “With the manual machine, we just bring the blade up against the work and it’ll set there,” Reichhold said, adding that the possibility exists for developing an attachment for CNC lathes in the future.
He noted the company is seeking a lathe builder to demonstrate the EDS attachment at the IMTS 2014 trade show, which takes place Sept. 8-13 in Chicago.
For more information about Electrical Discharge Saws Inc., Jackson, Tenn., call (877) MCH-TOOL. CTE
Related Glossary Terms
- bandsaw
bandsaw
Machine that utilizes an endless band, normally with serrated teeth, for cutoff or contour sawing. See saw, sawing machine.
- bandsaw blade ( band)
bandsaw blade ( band)
Endless band, normally with serrated teeth, that serves as the cutting tool for cutoff or contour band machines.
- computer numerical control ( CNC)
computer numerical control ( CNC)
Microprocessor-based controller dedicated to a machine tool that permits the creation or modification of parts. Programmed numerical control activates the machine’s servos and spindle drives and controls the various machining operations. See DNC, direct numerical control; NC, numerical control.
- feed
feed
Rate of change of position of the tool as a whole, relative to the workpiece while cutting.
- heat-affected zone
heat-affected zone
That portion of the base metal that was not melted during brazing, cutting or welding, but whose microstructure and mechanical properties were altered by the heat.
- lathe
lathe
Turning machine capable of sawing, milling, grinding, gear-cutting, drilling, reaming, boring, threading, facing, chamfering, grooving, knurling, spinning, parting, necking, taper-cutting, and cam- and eccentric-cutting, as well as step- and straight-turning. Comes in a variety of forms, ranging from manual to semiautomatic to fully automatic, with major types being engine lathes, turning and contouring lathes, turret lathes and numerical-control lathes. The engine lathe consists of a headstock and spindle, tailstock, bed, carriage (complete with apron) and cross slides. Features include gear- (speed) and feed-selector levers, toolpost, compound rest, lead screw and reversing lead screw, threading dial and rapid-traverse lever. Special lathe types include through-the-spindle, camshaft and crankshaft, brake drum and rotor, spinning and gun-barrel machines. Toolroom and bench lathes are used for precision work; the former for tool-and-die work and similar tasks, the latter for small workpieces (instruments, watches), normally without a power feed. Models are typically designated according to their “swing,” or the largest-diameter workpiece that can be rotated; bed length, or the distance between centers; and horsepower generated. See turning machine.
- sawing
sawing
Machining operation in which a powered machine, usually equipped with a blade having milled or ground teeth, is used to part material (cutoff) or give it a new shape (contour bandsawing, band machining). Four basic types of sawing operations are: hacksawing (power or manual operation in which the blade moves back and forth through the work, cutting on one of the strokes); cold or circular sawing (a rotating, circular, toothed blade parts the material much as a workshop table saw or radial-arm saw cuts wood); bandsawing (a flexible, toothed blade rides on wheels under tension and is guided through the work); and abrasive sawing (abrasive points attached to a fiber or metal backing part stock, could be considered a grinding operation).
- superalloys
superalloys
Tough, difficult-to-machine alloys; includes Hastelloy, Inconel and Monel. Many are nickel-base metals.