Manufacturers wishing to learn more about the latest CNC sliding-head and fixed-head turning centres from Citizen Machinery UK, but who perhaps are unable to attend the EMO 2023 machine tool trade fair in Hannover (18th – 23rd September), may be interested that shortly afterwards, from 3rd to 5th October, the company will hold an open house at its Turning Centre of Excellence in Brierley Hill.
The event will mark the 40th year that fixed-head lathe manufacturer Miyano’s products have been sold in the UK and Ireland, initially through the previous sales agent Macro Machine Tools. Since 2010, the brand has been a wholly-owned part of Citizen Holdings, which also offers Cincom sliding-head lathes as well as a range of turning machines incorporating auto-loading systems for rapid material and parts handling.
Citizen Machinery UK, with centres in Brierley Hill and Bushey, is the subsidiary of the Japanese manufacturing group serving the British and Irish markets. It is also the distribution hub for Citizen machines going into France, Spain, Portugal, Scandinavia, the Middle East, Africa and Australia.
Managing director Edward James commented, “We will not only be celebrating the 40th anniversary of Miyano’s presence in this market, but also seven years since the launch of our ground-breaking LFV (low frequency vibration) programmable chipbreaking software. The technology has helped to propel us to become the largest supplier of CNC bar-fed lathes in the UK and Ireland.
“There will also be a focus at the open house on the Miyano Eco Function, which ensures more efficient energy usage when operating the lathes, saving costs and helping the machines to perform at peak efficiency, an important tool in the drive to Net Zero.”
As usual, present throughout the event will be numerous partner companies involved in the supply of work holding, cutting tools, parts handling, barfeeds, production control software and more. Additionally, a Red Letter Day prize draw will be open to all visitors, with the winner receiving a £1,500 experience and hotel accommodation.
Headquartered in Bushey, Hertfordshire, Citizen Machinery UK has long been responsible for the Japanese watch group’s CNC bar-fed lathe sales in Britain and Ireland, while also being a distribution hub for sales of machines in France, Spain, Portugal, the Nordic Countries, the Middle East and Africa. Additionally, it works closely with subsidiaries in Italy and Germany. Underlining its international standing within the group, the UK subsidiary has spread its wings much further to join forces with a dealer in Australia, Headland Technology, based in Victoria.
Operating also from centres in Sydney, Perth and Brisbane, the company serves the Australian and New Zealand markets. It already represents 20 global brands covering machine tools, storage systems and metrology equipment. With around 75 highly skilled technical personnel in sales, applications and service, it is the perfect fit for Citizen Machinery. The independent technology consultant and equipment supplier focuses in particular on Industry 4.0 networked production and factory automation solutions designed to improve the profitability of its high-profile customer base.
A Citizen Cincom L32-XIILFV is being delivered to the dealer and will be exhibited on the Headland Technology stand at the Austech 2023 show in Melbourne from 9th to 12th May. The top-specification sliding-head lathe has nine CNC axes, including a Y2 axis on the back tool post and +90 / -45 degree B-axis swivel on the front gang tool post to enable angled holes to be drilled at either spindle. The model will also have low frequency vibration functionality for advanced chipbreaking of materials that normally generate stringy swarf.
Owen Gibbons, European Sales Manager at Citizen Machinery UK commented, “I am extremely proud to announce the newest addition to our ever-expanding dealer network, Headland Technology. It provides us with an exciting and unique opportunity to expand our international activities. Together with our end-users, we are looking forward to reaping the benefits of partnering with Headland Technology.”
In early October 2022, Citizen Machinery held a three-day open house at its Brierley Hill facility, which was visited by 176 people, up 28 percent compared with the previous year’s event. They represented 63 companies, 23 percent more than were hosted last time.
Owing to the seniority of the attendees and others who had expressed interest but could not attend, the tally of 25 new machine orders placed by 18 companies during October was a record for a single month. Half were for the company’s Cincom sliding-head turning centres and the remainder for Miyano fixed-head lathes.
As in previous years there was a constant stream of visitors from the start, keen to see the many live demonstrations. More than half the total attendance was welcomed on the middle day, Wednesday 5th October, due in part to the popularity of the traditional curry night. The supplier village at the show comprised mainly third-party suppliers to Citizen Machinery and all reported a high level of interest over the three days.
There was a promotion throughout the event, whereby any company that visited and placed an order was entered into a prize draw for a pair of hospitality tickets for the British F1 Grand Prix next year. The winner was Willenhall-based fastening products manufacturer NDB Engineering, which ordered a Miyano ABX-80SYY.
Following the same theme, there was an F1 car simulator competition. The person clocking the fastest lap won a bottle of champagne, an accolade that went to Raphael Poulequin of Renthal, Stockport, a world leading producer of accessories for motorcycles and mountain bikes. There was also a daily draw for a Citizen smart watch.
Due to unprecedented growth in sales of Cincom sliding-head and Miyano fixed-head turning centres, which has doubled Citizen Machinery UK’s turnover since 2016, the company has decided to increase the number of its area sales managers from five to six in order to maintain the high level of customer support for which the supplier is renowned.
Consequently, two promotions have been made within the existing business. Simon Fitzpatrick will serve Ireland, Scotland and territories in the north of England, while James Taylor will look after the south-west. Both have excellent technical expertise and product knowledge gained in applications.
At the same time, Tony Nolloth has been appointed UK & Ireland Sales Manager to coordinate full-time the activities of all sales territories. He is well placed to fulfil his new role, having previously been responsible for sales in the south-west and having gained a wealth of knowledge and experience of the company and its products since joining in 1989.
Edward James, managing director of Citizen Machinery commented, “Our success over recent years has been largely down the introduction of the proprietary LFV (low frequency vibration) chip breaking function in the control system of our Cincom lathes, coupled with robust mechanical enhancements, which are now also available on selected Miyano models.”
“In the last five years since the technology was launched, we have sold 600 machines to bring the installed base of our lathes in the UK and Ireland to approximately 5,000. Last year we achieved our second best turnover and even during the height of the pandemic in 2020 we hit 82 percent of our sales target.”
“Another pillar in achieving this outstanding performance has been a dramatic increase in deliveries of our fixed-head lathes, the range of which has expanded considerably. A decade ago Miyano products accounted for just 10 percent of turnover whereas today they make up almost half of sales.”
Customised, automated, proven
A facet of the supplier’s business central to its success is that its engineers are always available to provide advice, ensuring that customers receive exactly the right production solutions for their applications. It applies equally to new purchases and to machines already installed and running. The ethos is that only if users are optimally served can the Citizen brand grow strongly.
To this end, the company inaugurated in early 2021 a solutions centre at its Bushey headquarters to design and assemble customised production cells. The service encompasses full applications engineering support including programs, tooling, additional functions such as cleaning and packaging, and comprehensive machining trials prior to acceptance, delivery, commissioning and training. Solutions can be either stand-alone or integrated into larger manufacturing plant.
Automation to allow lights-out production and minimal operator attendance often plays a part, consistent with the increasing demand for Industry 4.0-compliant manufacturing systems. So also does integration of other processes in the working area of the lathes, such as laser cutting, to enable one-hit machining of complex parts.
Projects are frequently demanding in terms of their scope, level of innovation, process capability and return on investment. Despite these constraints, there will always be a sound business case for what Citizen Machinery delivers. It will be pragmatic, process-optimised and cost-effective, not necessarily the top solution possible, which may be overly expensive and take too long to amortise.
Freeing space in Bushey to house the solutions activity was made possible by the opening in July 2019 of a 680 square metre turning centre of excellence in Brierley Hill. That in turn was only sanctioned by the Japanese parent company due to buoyant sales of its products in the UK and Ireland. It is a classic case of success breeding success, which has resulted in Citizen Machinery becoming the largest supplier of bar-fed lathes into these markets.
Citizen Machinery’s ground-breaking LFV (low frequency vibration) chip-breaking software, which forms part of the operating system in the controls on some of the manufacturer’s sliding and fixed head mill-turn centres, will feature strongly at MACH 2022 as this year marks the fifth anniversary of the technology’s launch. The principle of operation is distinct from, and superior to, pecking macros programmed into individual machining cycles.
The patented system is gradually being rolled out across the company’s Cincom sliding head lathes, initially on the main spindle and more recently also on the sub spindle. To enable this, the construction of the machine models is systematically being strengthened to withstand the rigours of the momentary air cutting that creates the chip-breaking effect. There will be five Cincom machines on show at MACH 2022 equipped with LFV. A pair of Citizen’s Miyano fixed head lathes also benefits from the technology, one of which will also be exhibited.
The chip-breaking functionality can be switched on and off by G-code during a cycle, when deemed expedient, as if it were part of the program. The size of the actual chips can also be predetermined, as close control is maintained over the relationship between spindle speed and LFV oscillation of the tool by tens of microns, which has the effect of repeatedly retracting the tool tip clear of the workpiece. Coolant is able to penetrate the cut more efficiently, so tool life is extended and surface finish is improved.
Stringy swarf is therefore a thing of the past, even when machining difficult to chip materials like stainless steel, aluminium, copper and plastics. The need for manual swarf clearance is avoided, raising productivity and unattended running time, while the risk of damaging the workpiece and tool is removed. Futhermore, depth of cut may be increased substantially, raising productivity.
Three modes of LFV may be selected for machining with static and driven tools. The first is ideal for turning and grooving of outer and inner diameters, the second is best suited to micro-drilling operations that require high surface speed machining, while the third offers vibration-free thread cutting.
Sliding and fixed head lathes on show
(machines in bold are described in more detail below)
A total of 12 bar fed, sliding and fixed head mill-turn centres will be demonstrated under power on the Citizen Machinery UK stand at MACH 2022 (Hall 20, stand 150), including an automated production cell with integrated loading and unloading. Accent will also be placed on high technology software and mechanical enhancements that extend the scope and efficiency of machining on the Japanese-built lathes.
Making its world debut will be the new, 20 mm bar capacity Cincom L20-XIIB5LFV. The series-5 Cincom M32-VIIILFV will appear for the first time at a MACH show, as will the fixed head Miyano BNE-65MYY. Both have been redesigned to offer more power and flexibility and have been fitted with the latest Mitsubishi 800-series touchscreen control. Consequently, the latter machine is Citizen’s first 65 mm capacity lathe to offer superimposed machining, which allows three tools to be in cut together under simultaneous 5-axis control for elevated levels of productivity.
On show for the first time will be a Cincom L32-XLFV with integrated, high-speed laser cutting, a capability that was originally developed for efficient production of apertures in thin-wall stents on smaller Citizen sliding head lathes.
There will be a Cincom D25-VIILFV exhibited for the first time at a MACH show with the proprietary chip-breaking software. As on many other sliding head lathes manufactured by Citizen, the user has the advantage of being able to remove the guide bush for more economical material usage when producing shorter components up to typically 2.5 times the bar diameter.
A further highlight will be a Cincom A20-VIILFV, the first Citizen lathe to be equipped with multi-axis LFV software in a Fanuc-based Cincom control dedicated to this machine model.
The exhibition will also feature the first showing at a national exhibition in the UK of the 12 mm bar capacity Cincom L12-XLFV with five rear-facing static and driven end-working tool positions and the addition of a Y-axis on the counter spindle to mirror the main spindle’s three axis movements. The machine is intended primarily for production of dental abutments and implants, as well as other complex components.
From the Miyano stable, the ABX-64THY with 80 mm bar capacity and an ANX-42SYYLFV with Fanuc control will also make their debuts at a national show in the UK. Making another appearance at MACH to illustrate automated chucking will be the twin-spindle Miyano GN-3200W equipped with a high-speed loader capable of achieving high levels of productivity. The compact, rigid, thermally symmetrical machine offers a wide choice of infeed/outfeed devices, single or double high-speed gantry loaders, and transfer and turnover units, making the machine ideal for automated production.
Rounding off the exhibits on the stand will be an educational area explaining the latest Citizen software. It includes Eco Function hybrid technology that automatically saves energy through the intelligent use of power during non-cutting periods, underpinned by clear, on-screen graphical information showing present, maximum, cumulative and historical power consumption values. The next iteration of Alkart Wizard for off-line programming will also be in evidence, as well as Citizen’s Industry 4.0 capabilities encompassing the latest machine networking and monitoring functionality.
Debut of the new L20-XIIB5LFV sliding head lathe
The Cincom L20, Citizen’s best-selling sliding head lathe, has been upgraded to simultaneous 5-axis control via the improved, super-fast M850VM CNC with 15″ touchscreen. The new L20-XIIB5LFV allows multi-axis programming for superimposed machining with up to three tools in cut at the same time. It makes the machining of complex parts faster and easier and improves process stability.
The machine has a B-axis whose swivel range has been increased to 110 degrees, allowing more complex machining to higher accuracy at the main spindle, while the number of turning tools has been raised to six. Other improvements include a larger pitch between adjacent tools on the opposing and back tool posts to facilitate setting and reduce set-up time, a higher specification sub-spindle for improved productivity and the ability for LFV to be used when reverse-end machining.
First national showing of the Cincom L12-XLFV
For efficient machining of dental abutments, a minimum of five rear-facing end-working tool positions including driven stations is required, as well as the addition of a Y2-axis to the X2 and Z2 movements on the counter spindle to match the three degrees of freedom on the main spindle. All these features are provided on the 12 mm bar capacity Cincom L12-X. Previously, to obtain this level of functionality, a user would have had to purchase a 16 mm or even 20 mm capacity lathe, unnecessarily large and expensive for production of such slender components.
In this latest type-10 lathe, a built-in 12,000 rpm motor drives the counter spindle and acc/dec times have been reduced, promoting higher productivity. Rapid traverse at 35 m/min in all axes contributes further to minimising idle times. A modular tooling system has been adopted for the gang and back tool posts and an extensive variety of tooling layouts up to a maximum of 38 cutters is possible, including the ability to drill angled holes.
L32-X sliding head lathe exhibited for the first time with laser cutting
Launched in mid-2019, the Cincom 8-axis L32-XLFV will be on show for the first time at a MACH exhibition, without the optional LFV software but with the addition of high-speed, in-cycle laser cutting. The technology, which was originally developed for efficient production of apertures in thin-wall stents, is capable of fulfilling a wide variety of additional operations when machining tubular stock, or bar after it has been drilled longitudinally.
The development provides the option of in-cycle production of burr-free holes as small as 0.2 mm diameter and features such as spiral cuts with a 0.025 mm kerf. Consistent and accurate radii of less than 0.1 mm in the corners of slots can be achieved without risk of tool wear or breakage and at a far faster rate than is achievable by a separate EDM process. The non-contact, deflection-free, swarfless machining unit, deployed in the gang tool post, greatly expands freedom of design in the medical, electronics and many other industries.
Redesigned M32-VIIILFV sliding head lathe offers 5-axis machining
Although already shown elsewhere, for example at EMO 2021 in Milan, the new flagship series-5 M32-VIIILFV sliding head lathe with Mitsubishi M850W control will occupy a prominent position on the Citizen stand. The 10-axis machine has undergone a fundamental makeover and is considerably more robust than its predecessor, with larger and more rigid ballscrews and a bed that is 500 kg heavier, bringing the total installed weight to 4.3 tonnes.
The 10-station turret, which runs on hardened box ways, incorporates a new tooling system employing a single, heavier duty, 2.2 kW drive to an increased number of live cutters. Only the selected tool rotates – a world first for Citizen. The gang tool post has been equipped with 1.5 times faster live tools powered by a 2.2 kW motor, as well as a programmable, 9,000 rpm B-axis to enable simultaneous machining in five CNC axes rather than four; while the back tool post with Y-axis now has adjustable-angle tooling. Both features enable production of more complex parts, with three tools in cut at the same time.
Cincom D25-VII gains LFV
Since it was launched at the last MACH exhibition in 2018, Citizen has incorporated its chip-breaking software into the 12-axis, 25 mm capacity Cincom D25-VIILFV CNC mill-turn centre, which will be on show this year. The optional upgrade considerably enhances the lathe’s production efficiency. Operational flexibility is maximised by deploying up to 59 tools in the cutting area.
The latest D25-VII features the Industry 4.0-ready Mitsubishi 800 CNC system with touchscreen and QWERTY keyboard, which also provides triple axis control groups for simultaneous cutting with three tools. The contact angle between each cutter and the component is optimally maintained during production, enhancing surface finish, reducing cycle times and extending tool life.
New Miyano BNE-65MYY fixed head lathe with Mitsubishi 5-axis CNC for superimposed machining
Complex components up to 65 mm diameter may be turned and milled from bar on the new Miyano BNE65-MYY 10-axis fixed head lathe. Equipped with two Y-axis turrets, one positioned above and the other below the centreline of the twin-opposed spindles, considerable flexibility is provided for balancing front and back working cycles. The 8-tonne machine was introduced in the autumn of 2020 and is therefore making a first appearance at a MACH show.
Two-axis movement of the sub spindle facilitates superimposed machining under the control of a Mitsubishi M830W. Tooling on both faces of the top turret can simultaneously cut front-end features on bar stock and reverse-end features on a parted-off component. With the lower turret also working at the main spindle performing pinch turning, milling or drilling, for example, or perhaps OD turning while axial drilling is in progress above, three tools may be in cut at the same time.
ANX-42SYYLFV with Fanuc control
Also of double Y-axis configuration, the ANX-42SYYLFV is one of just two Miyano lathes currently to offer LFV, the other having only one Y-axis. The compact, 42 mm bar capacity, 10-axis machine is ideal for OEMs and subcontractors keen to leverage the quality and productivity of a Miyano lathe and at the same time standardise on Fanuc controls on their shop floor for the sake of operator familiarity and compatibility with other machines.
In addition to LFV software, the 15-inch XGA (extended graphics array) touch panel Fanuc 31iB control features a new Citizen HMI and incorporates the company’s multi-axis technology to allow 3-axis simultaneous cycles, double Y-axis cutting and superimposed machining with three tools. Commonality of tool holders with Citizen’s popular BNA range of Miyano lathes leads to cost savings for existing users of the supplier’s equipment.
First national showing of 80 mm capacity Miyano fixed head lathe
The largest bar capacity CNC lathe in the Citizen Machinery product portfolio is the new 12-axis Miyano ABX-64THY, a fixed head model also launched in the autumn of 2020 and therefore new to MACH. It has twin-opposed C-axis spindles and three Y-axis turrets moving over hand-scraped box ways, providing maximum rigidity. Originally designed for mill-turning parts from 64 mm diameter stock, the lathe can now be uprated for continuous, automated, unattended production of components from bar up to 80 mm diameter. Maximum billet size when chucking is 165 mm diameter.
The three 12-station live turrets can be in cut simultaneously to achieve very high levels of productivity. Two turrets are positioned above the spindle centreline and are dedicated to working at the 15 kW / 2,750 rpm main spindle and 7.5 kW / 5,000 rpm counter spindle respectively. The other turret is located below and has unrestricted travel to operate at either spindle and provide flexibility for balancing front and reverse end machining operations, or to deploy a tailstock centre to support shaft-type components being machined in both spindles. Again, control is by a Fanuc Series 30i-B.
The leading supplier of bar-fed sliding-head and fixed-head CNC turning machines to the British and Irish markets, Citizen Machinery UK, has reported a successful open house. The first since the start of the pandemic, excluding a few virtual events, it was held at the company’s headquarters in Bushey from 12th to 14th October 2021.
There was a steady stream of visitors over the three days. Numbers were down compared to previous shows, with 100 visitors representing 52 companies attending. Some people are still wary of travelling due to coronavirus, but by far the main reason given for not visiting was pressure of work.
Orders for 15 machines valued at £2,321,000 were either placed or committed to verbally during the show. Three of the orders were from customers who had registered but could not attend or who had not planned to visit.
More than two-thirds of the lathes will be supplied with the manufacturer’s proprietary LFV (low frequency vibration) programmable chip breaking software. Launched five years ago, it has transformed the ability of manufacturers to manage swarf when turning, threadcutting and drilling malleable metals and plastics.
Managing director Edward James enthused, “Our open houses are known for their feelgood factor and we like to entertain as well as take orders.
“The customary curry evening on Wednesday was very popular as usual and boosted attendance that afternoon and on the Thursday.
“We organised a Six Nations rugby draw each day for a pair of tickets to see the England v Ireland match in March 2022. There was also a daily prize draw for a Citizen watch.”
Visitors to the open house were additionally able to see the activities of Citizen Machinery UK’s Solution Centre in Bushey. It has transformed the traditional showroom into a facility for configuring and proving out complex automated machining cells, often with special functions such as in-cycle laser cutting, peripherals, software and robotic cleaning and packaging. The centre also doubles as a permanent exhibition of mill-turn solutions and software.
Citizen Machinery UK has announced that it will hold an open house at its Bushey, Hertfordshire headquarters and recently opened Solutions Centre from 12th to 14th October 2021, the week after the EMO international machine tool show finishes in Milan.
The company sells its Japanese parent company’s sliding-head (Cincom) and fixed-head (Miyano) bar-fed CNC turn-milling centres into the UK and Irish markets, as well as being the distribution hub for Citizen machines going into France, Spain, Portugal, Scandinavia, the Middle East and Africa.
Managing director Edward James commented, “We are delighted to be able to reintroduce the physical in-house exhibition format, where people can actually attend and network with others, rather than having to contend with the virtual shows we organised during the pandemic.
“We will not only be celebrating the return of this annual event but also commemorating a true milestone in the development of Citizen Machinery UK, as the open house will mark the fifth anniversary of the launch of our ground-breaking LFV (low frequency vibration) chip breaking software.”
This innovative, game-changing technology is to be showcased and there will be demonstrations to explain how it has helped boost CNC machining productivity globally. The company is also offering a sneak peek at some of the projects it is working on in the newly opened Solutions Centre.
To satisfy the needs of its widening customer base, Citizen Machinery UK has recently taken on five new employees. The ongoing recruitment campaign is essential to underpin the company’s position as the largest supplier of sliding-head (Cincom) and fixed-head (Miyano) bar-fed CNC lathes into the UK and Irish markets.
Citizen Machinery UK’s managing director Edward James commented, “We have expanded our business dramatically over the past few years. It is essential we keep our headcount commensurate with the increasing level of business to ensure our long-term success.
“This is especially important for our UK operation, as we are also the distribution hub for Citizen machines going into France, Spain, Portugal, Scandinavia, the Middle East and Africa.
“We are continually looking for candidates to strengthen our departmental teams and fervently believe that investment in staff is a top and ongoing priority, both to sustain growth and for succession planning and promotion.”
The level of success achieved by the UK operation enabled the management team to persuade the Japanese parent company to invest more than £3 million in a new turning centre of excellence in Brierley Hill, which opened in 2019 and concentrates on preparing deliveries to customers. It operates alongside the headquarters in Bushey, which has been made the centre for configuring and supplying bespoke manufacturing solutions.
The first new recruit, who joined as a service engineer towards the end of last year, is Gloucestershire-based Timothy Baldwin. He has a strong background in CNC turn-milling machine programming, setting and operation in the aerospace, motorsport and toolmaking sectors.
The newest member of Citizen Machinery UK’s applications engineering team arrived shortly afterwards. Martin Gregory lives in Birmingham and is well located to serve customers in the Midlands and to support the Brierley Hill operation. He has several years’ directly relevant experience working in the machine tool industry and is a valuable addition to the team.
Mark Harris, whose first day with the company was during early November, has considerable experience as a field service technician as well as having extensive knowledge of machine tool technology. Living in Solihull, he has been recruited into the servicing and installation team.
Rebecca Hancock joined as another service technician. She completed her apprenticeship during a five-year term at a superabrasives company in Gloucestershire and has experience working in the aerospace, F1, nuclear, defence and petrochemical industries. During that time she learnt to program, set and operate various machine tools including twin-spindle CNC lathes. She recently relocated to Walthamstow in north London.
That three of the first four new arrivals were recruited to the CMSure service and maintenance side of the business is no surprise. Citizen Machinery UK is finding that, due to uncertainty caused by Covid-19, there is a nervousness in some manufacturing companies to invest in new plant. It has resulted in a corresponding increase in the popularity of keeping existing machines in the field in peak operational condition and demand for service and maintenance support has never been higher.
The fifth recruit was north London-based Aaron Lewis, who joined from a leading workholding equipment supplier where he was a design/project engineer. Prior to that he studied design engineering at university. He is now supporting the customised production solutions team in a systems role at Citizen Machinery UK’s Bushey headquarters, working on integration projects and machine modifications.
A fourth variant has been added to the versatile Cincom L20 sliding-head CNC turning centre range from Citizen Machinery UK. The top model, L20-XII, which has a 135-degree swivelling B-axis mounted on the gang tool post for working at either of the opposed spindles, is now available with an automatic tool changer (ATC) for swapping up to 30 mm diameter cutters in a chip-to-chip time of four seconds. Both the tool carrier and magazine move in the Y1-axis to effect tool change.
Believed to be a first in a Swiss-type turning machine, the ability to exchange 12 different cutters in the lower position of the B-axis carrier greatly extends the machine’s versatility when executing angled crossworking or end facing operations. A 13th tool is fixed in the upper position on the carrier. While the cutters are normally live for performing drilling, slitting, hobbing or multi-axis milling, positions may be filled by turning tools if expedient.
The total number of tools that may be mounted in the working area of the Cincom L20-XIIATC is 34, providing considerable flexibility to ensure that components are machined in as few set-ups as possible, normally one. Cutters are driven by a 2.2 kW motor at up to 12,000 rpm, so even small diameter mills are capable of productive metal removal rates.
As its designation implies, the lathe is designed to turn components from 20 mm diameter bar, although oversized options allow up to 25 mm diameter material to be accepted. Another feature contributing to the lathe’s versatility is the ability to switch over quickly between Swiss-type operation and non-guide bush turning for more economical production of shorter components up to 2.5D. This mode results in less bar wastage due to the shorter remnants and is well suited to coping with tight drawing tolerances and close bore-to-OD geometry. The removal of the guide bush also means that the diameter of the stock material does not have to be tightly controlled.
To underscore the flexibility of use that is possible with this machine, it is noteworthy that it can be supplied in an LFV version with Citizen’s patented, programmable, low frequency vibration chipbreaking software. Furthermore, laser processing can be integrated to provide almost limitless possibilities for creating burr-free geometric shapes or precision holes as small as 0.2 mm diameter in tube or predrilled solid bar.
Building on the strengths of previous generations of Miyano fixed-head mill-turn centres, the BNA-42SY is Citizen Machinery’s latest addition to the range. The CNC lathe is the first BNA model to have a 12-station turret giving ± 35 mm of Y-axis movement, all tool positions now being live, and a new design that lends itself to easy automation.
Compared with current BNA models, machining efficiency has been upgraded by more powerful spindle motors, which are rated at 7.5/5.5 kW (15min/cont) for the 6,000 rpm main spindle and 5.5/3.7 kW for the 5,000 rpm sub spindle. Acceleration and deceleration are quicker on both spindles, improving productivity further by minimising idle times.
The machine’s rigid bed, the weight of which has been greatly increased to 1,823 kg, brings thermal control advantages and more capacity to house a larger coolant tank. The base casting has been prepared with space at the right hand side for robotic load / unload equipment. If a user intends to take advantage of automation, the machine can be supplied with a swarf conveyor that exits to the rear as an option.
The automation may be employed solely for unloading components that have been mill-turned from bar stock up to 42 mm diameter, either directly from a spindle or via a parts catcher and conveyor. Alternatively, or in addition, it may load and unload billets or near net shape workpieces like castings or forgings up to 135 mm in diameter. A workpiece stocker is positioned at the right hand side of the machine to accommodate the finished components.
Mounting points have been included to provide an option to add an overhead gantry if only chucking is to be carried out, in which case a raw material stocker can be positioned to the left of the machine in place of the bar magazine. For complete flexibility in layout, top shutter and auto door options are offered.
At 285 mm, the turret’s Z-axis travel has been increased by more than 20 percent, expanding the machining range of this compact, space-saving lathe. The turret and spindles are mounted on hand-scraped box slideways for improved rigidity and damping characteristics, leading to high metal removal rates, prolonging tool life and maintaining high accuracy.
The diameters of the X- and Z-axis ballscrews have been upsized from 25 mm to 32 mm, increasing rigidity further. Forced lubrication is provided to the ballscrews in all axes, the BNA-42SY being the second Miyano lathe to benefit from this feature.
The latest FANUC 0i-TF Plus CNC system with 10.4″ colour LCD screen controls the machine. Cutting times can be shortened by simultaneously completing complex reverse-end turning and milling at the sub spindle while front-end machining is ongoing at the main spindle, despite there being only one turret. It is achieved by superimposed machining, where the sub spindle tracks the turret and compensates for its movements while it is cutting at the main spindle, enabling a machining cycle on a parted-off component to be executed using tools mounted on the reverse face of the turret. This can be accomplished due to the ability of the sub spindle to move in the X-axis.
As with all modern lathes from Citizen Machinery, both Miyano fixed-head and Cincom sliding-head models, the BNA-42SY is an environmentally friendly machine. Use of an inverter controlled hydraulic unit results in a large reduction in power drawn. Standby power consumption is just 0.661 kW, as servomotor readiness is automatically turned off when it is not needed, for example during program editing. Overall energy consumption can be visualised via a power monitor window on the control screen.