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CNC stoneworking systems are being used for a broad range of production demands, including unique custom pieces as well as large orders of identical pieces, such as hotel countertops. They are also used for jobs such as statues and memorials, where attention to detail is very important. No matter what the end product may be, the machines continue to advance stone design.
Newer CNC systems include the Omag Profiler, a routing and engraving machine, designed for marble, granite, limestone and glass. It is capable of working in 3 or 4 axes simultaneously, allowing operations such as carving, engraving, contouring and drilling. All axes movements are powered by brushless AC servo motors, which drive precision ball screws. Linear bearing and guides - both protected by PVC bellows - act as the machine ways. Moving components are lubricated by a centralized system, which is programmable through the computer. A frequency converter system controls the spindle, maximizing horsepower and torque. The spindle is ISO 50 tool change version. A saw blade up to 500 mm in diameter can be used with the spindle and rotated at a full 360 degrees to produce angular cuts. Omag machines are distributed in the U.S. by Bergman-Blair Machine Corp of Oyster Bay, NY.
It is possible to laser etch granite, marble, slate, ceramic, glass, wood, acrylic and leather with the Laser Master from Cam Tech of Calgary, Alberta, Canada. By taking a scanned or digital photos and resizing and editing them with Cam Tech design software, the machine can laser etch it onto one of these materials. The Laser Master can also be adapted to dispense specially formulated resins to create stained glass.
CMS North America, Inc. of Grand Rapids, MI, has two CNC machining centers for processing natural stone as well as engineered stone and glass - the Brembana Maxima and the Brembana Futura. The Brembana Maxima's maximum speed and single section mobile bridge structure offer versatility for all machining functions, including routing, drilling, milling, grinding, edging and polishing, scooping, lettering and carving. Machining operations are made simple with the 13.5-kW, 18-hp electro spindle, with a speed up to 15,000 rpm. Other features include a worktable measuring 142- x 102-inches, a linear tool crib with 22, 26 or 44 stations and EC Standards Certification.
When machining stone, the Maxima can process edge thicknesses from 10 mm to 400 mm, and it can machine intricate tri-dimensional pieces such as arches, moldings, pillars, high-reliefs and bas-reliefs.
The Brembana Futura is an innovative CNC machining center for machining and fabricating stone and glass. The Futura 3- or 4-axis numerically controlled working center has been developed to address needs of manufacturers with limited resources or smaller size production requirements. Its maximum speed and compact structure offer versatility for all machining functions, including sawing, drilling, milling, grinding, polishing, scooping, engraving and carving. The smooth work surface enables the operator to arrange the workpieces on the machine with optimum ease and safety. The Futura worktable can handle material with a maximum size of 141.14 x 70.86 inches. The fourth axis option allows for the use of flat and concave blades for straight or curved cutting. The standard model Futura is supplied with an 18-hp, 15,000-rpm electro spindle, and the tool station is supplied with 26 positions. When equipped with the optional tilting head, the Futura is suitable for polishing recessed kitchen countertops. Parametric software allows for effective programming of the machine.
A machine that has recently been introduced by U.S. Granite Machinery of Barrington, IL, is the Magnum. The Magnum's features include linear bearings for rigidity and accuracy, a 10-hp spindle, a PC modem for online tech support and a 3-hp "liquid ring technology" vacuum pump system. It also has an auto tool change capability and a controller that will accept measurements in inches or metric as well as .DXF files, digitized or CAD files. Preloaded with "stretchable" kitchen and vanity sizes, the Magnum is designed to be easy to run.
Intermac has also introduced a new CNC stoneworking machine, called the Jet, available through AGM of Pineville, NC. The machine utilizes a gantry structure, which allows for convenient loading and unloading. The unique spindle design permits continuous production, and the machine can be continuously loaded, since machine operators can place the next piece while the machine is working. The Jet has a usable bed of 59- x 118-inches and 22 tool positions, allowing the greatest flexibility for machining centers of this type, according to the company. With an optional fourth axis, bowl holes and shaped lamination strips can be cut simply and affordably. All Intermac machines come equipped with state-of-the-art Allen Bradley/ OSAI Series 10 controls, which are known for their reliability. The Jet offers many distinct advantages, such as the on-the-fly tool wear compensation and a self-contained robust structure. The Intermac Jet has a user-friendly CAD/CAM system, which allows operators with a limited experience to be trained in a short time.
The mechanical engineering company Burkhardt GmbH of Bayreuth, Germany, has developed a 5-axis universal machining center called the Model 595. Intelligent software paired with the flexibility of a universal tool slide allows the working and finishing of table, kitchen, bathroom tops and monuments. The pre- and post-working of the edges and chamfers and the accurately contoured circumferential side machining are carried out in one clamping. The universal tool slide makes it possible to machine the workpieces on five sides. With kitchen tops, the 595 creates the cutouts, drain surfaces, bore holes and grinds the edges of inner and outer contours. With monuments, the different chamfers and radii are machined-curved and straight edges are ground and polished.
Northwood Machine Manufacturing recently built the new model N-138-S, distributed by Vic International of Knoxville, TN. The machine has an X-axis (bridge) of 156 inches, a Y-axis (table) of 96 inches and a Z-axis of 12 inches. It also features a 20-hp spindle that goes from 3,000 to 15,000 rpm. The tool storage has 28 total positions and the software is Northwood stone router with Alpha CAM engine.
Breton recently introduced several new machines, available from Performance Machine Systems USA, Inc. of Deerfield Beach, FL. The Contourbreton NC 400 is the evolution of the NC350 series. This machine has a spindle with pneumatic pressure control to polish stone surfaces. Specific software functions optimize the polishing pressure according to the material and polishing phases. This solution allows the execution of pockets through a fully automated cycle, using standard tools. It has a carousel tool store with 27 positions that makes it possible to change tools without stopping the machine operation and an axis advancement speed increases to 60 m/min. The machine is also equipped with a "Z" axis travel of 400 mm, a sensor with radio transmission, laser presetting, a laser beam precision device, a continuous fourth axis and a motorized double workbench. The Contourbreton NC 400 comes with high-performance software, Bretoncam, which is improved with new functions such as Technological Macros, automatic budgeting and the automatic control of up to 10 tools of different, but combined, typology.
The Contoursaw FR/NC is two machines in one - a contouring machine and a saw. It is equipped with a Siemens 810D control, which controls 5 axes and allows the program to make it possible to execute the most complex operations on this user-friendly interface. CAD-CAM software allows the most sophisticated operations available today by the advanced numerical control unit, according to the company. The Z axis travel is 500 mm and permits deep dishing with high spindle power of 15 kW and operates up to 6,000 rpm.
Another machine from Breton is the Goldenedge CTX, a single-spindle numerical control machine to cut flat or profile edges and upper and lower chamfers on granite, marble and engineered stone materials. A laser system checks the profile, diameter and length of tools and pre-sets them. It can machine materials up to 60 mm thick and work lengths up to 3,500 mm without having to adjust the machine.
The Spiderbreton FR/PC is a fast and versatile bridge saw controlled by a personal computer. All the movements of the machine are powered by drives that are actuated by inverter and controlled by encoder. The machine can hold a diamond blade with a diameter up to 725 mm, and the 1200 model diameter holds a blade up to 1200 mm. It comes with a PC/monitor with touch screen display to make programming the machine easy and quick.
The CSL 800 is a numerical control machining center from Bideseimpianti. The machine has 3 interpolated axes for the realization of various profiles like bas-reliefs, high reliefs, tubs, irregular surfaces, artistic shapes, engraving of letters, bath sink surfaces and kitchen surfaces. Programming is done through a CAD/CAM system.
All models are equipped with tool crib with automatic tool change. It is possible to personalize the machine according to the workings that the customer needs to produce.
For example, the addition of the scanner laser allows users to survey surfaces such as bas-reliefs with a 500-mm range, and to reproduce a file format from CAD/CAM, even with a survey resolution of 0.1 mm.
New to the U.S. market, International Machine Corp. (IMC) of Woodside, NY, and San Francisco, CA, presents the Contour 2000 CNC machine. The IMC Contour 2000 utilizes a Windows operating interface based on user-friendly software to allow fast learning and operation. The macro is based on standard designs of the most common working applications, such as vanity tops, kitchen tops, and shower plates. Simply choose a drawing, and the computer will automatically configure the specifications.
The L¿ffler LBZ CNC machining center, available from EuroStone Machine of Atlanta, GA, is designed for optimum precision and versatility. The linear tool holder has 22 stations, and tool changing is automatic. The machine's three axes run on digital servo drives with precision ball screws, guided by linear ball bearings. The machine's overall dimensions are 5,000 x 3,800 mm.
Z. Bavelloni S.p.A. is offering the Egar 250, a high-technology machine designed for high-quality, complex processing of stone. Useful in both large and small shops, it can produce unique pieces as well as process coarse material without an operator, the company reports. Making loading and unloading easier, the machine features an open top structure and mobile bridge on the Y-axis, which is built with electro-welded and normalized steel. Using 4-inch wheels, the working area and axis stroke can handle pieces up to 100 x 50 inches.
This machine is designed for drilling; milling; internal and external edging; artistic and geometrical bas-reliefs; writing with a candle tool; artistic and geometric engravings with a diamond candle tool; shaped pockets; execution of slant kitchen countertops with a polished finish of the top and edges; and execution of sinks machined from a block of marble or granite.
Equipped with ISO 40 tool store at 20 positions, an adjustable working plane from 0 to 1 degree for use with kitchen countertops is available upon request. Also, the spindle is separated from the motor and is not an electrospindle, enabling the operator to perform customary maintenance. Furthermore, the Egar 250 is equipped with a C axis that allows for a continuous 360-degree rotation of the tool. An optional head and disk can also process cuts and shaped blocks such as fireplaces and door frontals. The disk diameter ranges from 5 to 8 inches, and the maximum thickness a new disk will cut through is 3¿inches with the 5-inch disk, and 2 inches with the 8-inch disk. It is available from Z. Bavelloni USA Inc. of Greensboro, NC.