Metal Cutting: Milling, Drilling, and Boring
Automation solutions for machining parts speed manufacturing productivity
With the need for faster, more efficient metalcutting never more critical, manufacturers looking for the latest in milling, drilling, and boring machine tools can expect to see many innovations that spur process improvements and improve overall manufacturing productivity.
Among milling systems, demand has been strong for the venerable Bridgeport milling machine from Hardinge Inc. (Elmira, NY), notes Hardinge's Dave Barber, who observes that there are more than 350,000 of the machines installed and the market for such machines is still growing. Hardinge has added an updated version, the Bridgeport EZ Vision Automated CNC Mill, with a two or three-axis control that comes factory-fitted, not retrofitted, with power feeds on the Series I Standard Mill. According to the company, the control is easier to operate than a conventional CNC, and far more productive than manual machining.
New boring mills offer the latest capabilities in multitasking to help boost manufacturers' productivity. "We considered trends when deciding what to bring to IMTS, and multitasking is a trend seen in all machine tools, including boring mills," notes Ken Campshure of Giddings & Lewis Machine Tools (Fond du Lac, WI). "By using the capabilities of the live spindle and adding a contouring head or programmable boring bar, turning operations may be added to a boring mill. This reduces setups and makes it possible to machine parts that may be too large or awkward to rotate on a lathe. Contours, chamfers, tapers, internal part geometries, threads, and backfacing are just some of the operations possible. Reduced tooling costs and the ability to reach deep into a part are also advantages of this type of configuration."
At IMTS 2006, the RT 1250 machine that Giddings & Lewis will display features multitasking capabilities with a contouring head, programmable boring bar, and a C-axis vertical rotary table mounted on the built-in B-axis hydrostatic rotary table, Campshure says. "We'll demonstrate the contouring abilities of the multiaxis configuration by showing a straight line cut using both tables," he adds. "One aspect of boring mills that is never a trend but a constant is customers' need for a rigid machine. This has been a tradition of our boring mills that we've not only maintained but enhanced with all of our new boring mills, the most recent being the Floor-Type HBM. Wider way spreads, internal X-bracing, and more robust castings are a few of the ways we achieve a rigid cutting platform capable of heavy cuts and extreme accuracy. Machine rigidity may not be obvious at a show, and customers need to ask questions about construction to get a boring mill that has the performance they need."
Automated drilling systems also offer substantial advantages for manufacturers automating the process of drilling large numbers of holes as quickly and efficiently as possible. With automated systems like the Selfeeder line of drilling machines from Sugino Corp. (Schaumburg, IL), manufacturers can get precision with speed in drilling holes.
"For us, it's mechanical-feed drilling units, servo-feed drilling units that replace machining center operations," notes Sugino's John Fischer. "What we're finding is, the industry that remains in the USA is usually a bit more technical and it's a little bit more precise, and manufacturers are still looking for flexibility. What we offer is a new line, called Varimec, or Variable Speed Mechanical Feed units.
"What it does is it enables the customer to take the machining operation, at least the drilling operations off of the CNC machining centers, and accomplish more than one task at a time," Fischer adds. "A limiting factor to a machining center is that it only has one tool in the part at one time. We call it a Z-axis machining center. The Varimec is a quill-fed drilling unit. Internal to the unit is a larger-diameter quill and we've got linear slides built into the unit, and a big guidebar and leadscrew, so we have all the rigidity of a machining center. You could actually put side load on these; if you want to mill with them, you can.
"The burden rate on a machining center, even the lower-cost machining center, is that you still have to have a pretty technical operator there, and again, they're only drilling one hole in the part at a time," Fischer says. "So what you're getting with our machine is that you can have multiple operations completed at a time, without a sacrifice on the quality that you need for the holes. The nice thing about it is they're very flexible, because they're 100% programmable, so the customer can take the product and reconfigure it, and use it for a multitude of jobs."
In addition to a new Varimec model, Sugino is introducing a new tapping unit at IMTS. "We're also introducing a servo tapping unit that takes the same approach," Fischer says. "People are looking for more speed, but without sacrificing any of the accuracy, so we have a new option there with the servo-feed tapping unit. Another of our new introductions is our gun feeder line, which is being used for medical instruments to do brain surgery."
Sugino also will show a new CNC horizontal machine, the H15, for machining precision holes in applications including automotive variable timing devices, he adds. "This is another instance where a critical component now being manufactured in a lot of cars is the variable timing device, and there's a lot of machining on them that has to be precision-machined," Fischer notes, "and obviously automotive has to be done fast. What we're really after is someone that's looking for a little bit more speed, a little bit more accuracy, and more rigidity in a smaller unit. We're not producing big units, we're not loading up a tombstone or something like that doing 100 parts. It seems like this is the way the market's going, back to small cells or a group of common machines to run common parts."
The following products are representative of the equipment that will be shown in the Milling, Drilling, and Boring pavilion at IMTS 2006. — Pat Waurzyniak
The model S-36 arm enables the operator to tap and deburr holes as a secondary operation. It can be moved around the shop via a rolling table, which can also reduce material handling costs. The unit can tap from 0-80 to 9/16" (14.3 mm) in steel. With a working range of 14–51" (356–1295 mm), the unit stays perpendicular anywhere it is moved on the table. A larger motor is available to increase the tapping capacity to ¾" (19 mm).
FlexArm/Midwest Specialties Inc.
Ph: (800) 837-2503
Jig Boring Machine
The model 6CN jig boring machine scheduled for display has an X, Y, Z envelope of about 40 x 30 x 12" (1020 x 760 x 300 mm). It's being brought to the show in response to a resurgence in demand for jig borers. The company manufactures three models of jig boring machines.
Mitsui Seiki USA Inc.
Ph: (201) 337-1300
Bridges for Boring Head
Designed for use with the company's ABS KFK microadjustable boring head, these replaceable bridges permit boring diameters to 4.055" (103 mm). They are made from lightweight material with surface coating and integrated balancing compensation capability. For finish boring diameters from 1.496 to 4.055" (38–103 mm), two intermediate adapters and four replaceable bridges are used along with a basic ABS 50 tool body. For diameters over 206 to 1000 mm, the company offers modular bridgetype boring tools. In a modular design, this tool system consists of standard elements and elements selected for length.
Komet of America Inc.
Ph: (847) 923-8400
Bridgeport EZ Vision automated CNC mill utilizes the EZ Vision, a two or three-axis control that comes factory-fit (not retrofit) with power feeds on the Series I Standard Mill. The 2-D contouring capability lets the user machine angles and radii without a rotary table. A third-axis option is available to further enhance the machine's productivity. The operator can switch from manual to automatic operation at his/her discretion. With its canned milling and drilling cycles, as well as a graphics preview feature, the control allows operators to verify the machining program before running a part.
Ph: (800) 843-8801
The company's DigiBore precision boring system's range has been expanded to 8.189" (208 mm). Plus, axial grooving modules for the system are now available over its entire range of 0.118–8.189" (3–208 mm) providing grooving widths from 0.040 to 0.120" (1–3 mm). Outside turning modules are also new and available for diameters from 0.078 to 4.48" (2–114 mm).
Ph: (937) 885-1878
Horizontal Boring/Milling Machine
The company's newest machine, the BTH-110.R18 (H3) table-type horizontal boring and milling machine has high-speed machine capabilities. The H3, stands for high rigidity, high accuracy, and high speed. With linear scale feedbacks for X, Y and Z (options), this machine provides a positioning accuracy of +/- 0.00016" (0.004 mm) full length and a repeatability of +/- 0.00008" (0.002 mm). Spindle speed ranges from 6 to 4000 rpm, and rapid feed rate in X,Y, Z is 708.7 ipm (18 m/min), in W 236.2 ipm (6 m/min) and in B of 2 rpm.
Toshiba Machine Machinery Co.
Ph: (800) 275-8373
Roscamat 6000 and Roscamat 9001 are electronic threading machines, which use single-phase of 220 V power and a servomotor, allow a threading capacity from M2 to M27 (M33) and M3 to M36 (M42) respectively. They offer six different speeds and a wide range of programmable options such as speed control, turn control (rightwards, leftwards), automatic tool lubrication, depth control, and thread counter.
Ph: +34 93 876 43 59 (Spain)
Horizontal Boring Mill
Model BMC-110T2 horizontal boring mill incorporates a traveling column design with axis travels of 78.74 x 82.68 x 59.05" (2 x 2.1 x 1.5 m) in X, Y, and Z. The 35-hp (26-kW), 50-taper spindle has a maximum speed of 2500 rpm with travels up to 21.65" (550 mm) on the W axis. The machine comes standard with a 60-station ATC with an option for 90 tools.
Ph: (714) 898-2066
Submicron Boring Head
Submicron series of patent-pending boring heads have an easily read and play-free tool carrier for direct diameter adjustment accuracy of 0.001 mm/division. Inch-graduated heads will adjust to 0.00005" per division on diam. All six heads allow users to bore a range of 20–100 mm. The company's KA connection permits a wide range of spindle-interface requirements, and all bore ranges and tool lengths are identical to the manufacturer's existing tools. Integrated counterweight can be adjusted to bore diam by separate scale to permit high-speed operation. Tool-carrier locking system doesn't influence diam, and ensures repeatability.
BIG Kaiser Precision Tooling
Ph: (888) 866-5776
Horizontal Milling Machine
Made by FPT Industrie SPA, the Ronin is a traveling-column machine for high-speed finishing as well as rough machining. A ram-type milling machine, it has auxiliary milling heads for three-axis, 3+2 axis, and five-axis continuous-milling applications. Its design includes a draped column/saddle that reportedly yields more useable Y-axis working range. The ram housing is symmetrically centered within the bifurcated column. Inside the ram is a direct transmission assembly; a synchronous, continuously variable speed motor rated at 49 kW power, speed from 400 to 7000 rpm (up to 10,000 rpm), and 1180 Nm torque.
Ph: (800) 798-1689
Barfeed Milling Machines
Company's Mill 800 VMC will be demonstrated with several productivity enhancers including milling from bar. It's described as a bonafide milling machine, and the barfeed permits high productivity, and makes the machine wellsuited for lights-out operation. Milling from bar on this machine employs a 100-mm through-hole to feed bar stock to an indexer for five-sided machining. When the five sides have been completed, the part is automatically picked off the indexer, and the sixth side is finished. Machine accommodates up to 192 tools (HSK or CAT 40) with an optional magazine toolchanger.
Chiron America Inc.
Ph: (704) 587-9526
A portable unit intended for fast holemaking in fabrication shops or on-site applications, the model HMD925 power-feed portable magnetic drill weighs 37 lb (16.8 kg). It features a holemaking capacity of 7/16–1 1/4" (11–31.8-mm) diam through materials as thick as 2" (51 mm) using the power feed option (1 1/2" or 38 mm diam in manual mode), and the company's Rotabroach annular cutters.
Hougen Manufacturing Inc.
Ph: (810) 635-7111
Trak FHM-Series bed mills machines employ the ProtoTRAK SMX CNC, which enables users to transition between manual and CNC operation. Machine features include standard electronic head, electronic handwheels, and servomotors for rapids to 250 ipm (6350 mm/min). The TRAKing feature enables the user to run part programs in the CNC, and retain complete control of the machine feed. Cranking the handwheel runs the X, Y and Z axes as programmed. The machinist can run forward through the program, back up, or turn off the spindle to take a measurement during program run.
Southwestern Industries Inc.
Ph: (310) 608-4422
The TM-3 Toolroom Mill is described as combining the functionality and simplicity of a manual mill with the power and flexibility of the builder's CNC control, making it well suited for toolrooms and shops transitioning to CNC. The machine's 40 x 20 x 16" (1016 x 508 x 406-mm) travels in X, Y, and Z provide room for machining larger workpieces. It features a (peak) 7.5-hp (5.6-kW) vector-drive spindle that uses standard 40-taper tooling and spins to 4000 rpm. A 10 or 20-pocket toolchanger can be added for automatic operation.
Haas Automation Inc.
Ph: (805) 278-1800
Boring Head Adapter
The modular ScrewFit adapter for boring and precision boring heads will be featured with a line of boring and precision-boring heads. Due to the dimensions of this adapter, tools can be supplied for machining diameters of 0.079–2.75" (2–70 mm). The relevant adapters feature a cutting-edge orientation coordinated for precision boring to avoid withdrawal marks. ScrewFit tools are mounted using an open-jawed wrench. Using ScrewFit adapters reportedly reduces tool projection by around 30%. Tools come in a dual-flute version for boring and a single-flute version with precision adjustment for precision boring.
Ph: (800) 945-5554, Ext. 170
Horizontal Boring Mills
A rotary-table boring mill, the model RT 1250 has five-axis and multitasking capabilities. An optional C-axis vertical rotary table mounted on the built-in B-axis hydrostatic rotary table adds multiaxis machining and contouring capabilities. The entire range of boring mills is modular in design. Choices include various table styles and sizes, headstocks, controls, attachments, and X, Y, and W-axis travel options. The three headstock choices all include a programmable live spindle that allows drilling and tapping as well as added reach for boring. The two or fourspeed headstocks have 130 or 155-mm diam spindles.
Giddings & Lewis
Ph: (920) 906-2328
The RTM80 and RTM100 CNC milling machines are designed for milling, drilling, and tapping on large workpieces. They come standard with X, Y, Z travels of 78 x 35 x 28" (1981 x 889 x 711 mm) and 98 x 35 x 28" (2489 x 889 x 711 mm). Table sizes are 30 x 92" (762 x 2337 mm) and 30 x 112" (762 x 2845 mm), with max table load of 4000 lb (1816 kg). The 40-taper spindle is driven by a 15-hp (11-kW) AC digital Anilam servomotor Controller is an Anilam 6000.
Willis Machinery and Tools Co.
Ph: (419) 537-1717
Company will showcase the newly engineered Varimec lead-screw Selfeeder designed to meet manufacturing demand for smaller, more powerful, self-contained drill units capable of high accuracy in a wide range of metals and other materials. Systems are quill-fed drill units capable of precision endmilling and face-machining operations. Two electrically driven units are available, the SSV3 with 0.5 hp (0.4 KW) and the larger SSV5 unit rated at 3.25 hp (2.5 KW). Spindle runout for both models is under 0.0004" (0.01 mm). Depth repeatability is +/- 0.0008" (0.02 mm).
Ph: (630) 250-8585
This article was first published in the August 2006 edition of Manufacturing Engineering magazine.