TaeguTec has launched two new five-cutting edge insert lines – the RTMX and RTHX – with related cutters dedicated to stainless steel and difficult-to-cut materials used.
The RTMX is a press-to-size type line, while the RTHX ground type is dedicated towards high precision machining. Both lines offer a high positive rake angle for low cutting resistance.
Both inserts come in 10 and 12 millimetre sizes. Their chip formers are available in three types: MM, ML and MLL. The MM chip former is recommended for unstable conditions, MLL for stable conditions and ML covers the middle range between the MM and MLL types.
Both lines are available in standard and special grades. The special grades are made for any machining environment, even under harsh conditions due to their high wear resistance and toughness capabilities.
Cutters are available in end mills (ø32 mm), modular types (ø25-40 mm) as well as face mills (ø40-80 mm) and all are coolant capable for easy chip evacuation.
This 5-axis machining centre is designed specifically for small, complex, 3-D contouring of high-quality part production as typically seen in aerospace machining, medical manufacturing, high-end job shop and die/mould applications.
The D300 worktable offers a work area diameter of 300mm, accommodating workpiece sizes up to 450mm by 270mm and 120kg. The machine provides X-, Y- and Z-axis travels of 300mm, 500mm and 350mm, respectively, at feed rates of up to 60,000mm per minute. Rotary table axes offer rotational motion of 240 degrees (± 120 degrees) on the A-axis and a full 360-degree (continuous rotation) on the C-axis.
The machine comes equipped with a 15,000-rpm HSK-A63 spindle with 120Nm (42Nm continuous) of torque for flexible, high-speed machining of various workpiece materials including steel, aluminium and titanium. Optional spindle configurations include a 20,000-rpm HSK-A63 spindle and 30,000-rpm HSK-F63 spindle.
Makino uses direct-drive motor technology in the D300’s C-axis rotary table and A-axis trunnion for positioning accuracy and repeatability. The ultra-high-torque direct-drive motors also provide quality acceleration and rotary speed characteristics that can reduce cycle times of complex 5-axis simultaneous machining applications by up to 60 percent.
The D300 axis configuration is designed to deliver added precision performance. The length of the trunnion assembly runs parallel to the X-axis motion only, making the trunnion assembly deflection-free during quick axis motion for greater accuracy than traditional 5-axis configurations.
The machine features roller linear guides across all linear axes for rigidity and stiffness while maintaining productive rapid and feed rates. Y- and Z-axes are located above the worktable, with the X-axis located under the table to ensure a cantilever-free design and high positioning accuracies.
It employs the Makino Professional 5 Control, which provides a Windows CE graphical user interface (GUI) with touch-screen access, and the networking and storage capabilities of a data centre. This data centre features a flexible, user-friendly program and data management for quick, seamless changes from one setup to the next. Its built-in Ethernet networking capability offers ready integration to off-machine program storage.
Also featured in the D300 is the next-generation Super Geometric Intelligence (SGI.4) software developed specifically for high feed rate, tight-tolerance machining of complex, 3-D contoured shapes involving continuous tiny blocks of NC data that ensures production rates faster than standard CNC systems, while maintaining high accuracy. SGI.4 helps deliver the lowest cycle times and costs achievable by reducing machining cycle times on dies, complex cavities, and cores and medical parts by as much as 40 percent when compared to most other control technologies.
The tool centre point (TCP) control allows programming based on the tool tip so that tool-compensation features can be applied. Further TCP developments also improve the cutter path to achieve greater surface quality. Dedicated user-friendly screens simplify the overall application of 5-axis machining, and easy-to-apply functions prevent interference between the spindle and trunnion during automatic operation to improve risk-free production.
The H 12 machining centre from Takumi is a 3-axis, double column machining centre.
A direct drive spindle with up to 15,000 rpm allows for machining in the die and mould, aerospace, and other high-speed applications. It has 1,350 by 950 by 600 mm travels and a 30-station swing-arm ATC.
The machining centre has a 1,500 by 960 mm table and a maximum load of 1,800 kg. Optional devices include an oil mist device, oil mist collector and ballscrew cooling system.
The M200 Millturn can machine workpieces of up to two m in diameter, 14 m in length and 60 tons in weight.
The a new dimension in complete machining M200 MILLTURN WFL Millturn Technologies machine is built in different turning lengths and nominal centre distances, making the range of applications correspondingly diverse: large landing gear extensions, large crankshafts, shafts for turbines and for generators, large manifolds as well as shafts and rollers for heavy industry.
The turning-boring-milling unit can work on difficult-to-machine materials, and at up to 80 kW of power and 1800 Nm of torque with minimal vibration. The machine can work on any type of inclined machining due to its B-axis; it also supports WFL M200 MILLTURN 5-Axis CNC Lathes interpolation.
How are machine tool makers incorporating Industry 4.0 in their machining centres and beyond? By Michael E Neumann
Machine tool manufacturer Industry 4.0 Heller has been providing a range of products for decades, mainly comprising four and five-axis machining centres, mill/turning centres and flexible manufacturing systems.
In terms of Industry 4.0, the company is looking at even higher machine productivity and supporting consistent engineering chains. This also includes looking at supplementary machine functions, on-demand services and enhanced service capabilities.
Reducing Cycle Times With machine tool Industry 4.0
The company hopes to illustrate the importance of ease of operation, customised workpiece manufacturing and enhanced evaluation of existing data on three main fronts:
The Industry 4.0 Heller4 Operation is an operator-oriented user interface for the company’s machines. The use of touch controls at the tool/workpiece loading station enables Industry 4.0 robust operation. The new operator panel also allows specific programs from web environments to be run.
Secondly, Heller4 Services comprises of digital services. The Services Interface focusses on the transparency of Industry 4.0 manufacturing and maintenance processes. The module forms the basis for evaluations and statistics, thus providing support in reducing machine downtimes. Additionally, the visualisation of specific information, including status displays of axes, spindles or other assemblies, enables users to determine where and to take preventive measures in order to avoid unscheduled downtimes.
Finally, Heller4 Performance comprises the machine analysis for process and performance optimisation, time-synchronous extraction of real-time data into the internet as well as evaluation and graphical display, using an external cloud platform.
All this is aimed at reducing the customer’s cycle times, and thus workpiece costs, by providing greater productivity through greater ease of use of the machine, optimal integration into the network and expanded functionalities and service possibilities.
Additionally, flexible integration into existing production systems is also a focus, with new machining centres enabling continued use of existing tools from other Heller machines and the use of manual clamping fixtures. Adaptation of hydraulically operated clamping fixtures is also possible.
Active Evaluation
The company also founded a new business and technologies development division to explore new technologies in 2010, such as ways to reduce CO2 emissions and fuel consumption of combustion engines, electromobility, lightweight construction and Industry 4.0 machine tool.
In collaboration with a team from application development, application assembly and sales, the division developed the CylinderBoreCoating (CBC) process, a technology for the coating of cylinder bores of aluminium crankcases using electric arc wire spraying.
The company states that the coating results in a 50 percent reduction in friction forces between the cylinder and the piston ring, enabling a more compact crankcase design and significantly reduced cylinder bore spacing. This results in a reduction in engine size and weight savings.
Reduce Idle Times
The division also developed and launched solutions in response to Industry 4.0, called Heller4Industry. A feature would be tool provisioning. Tool magazines are usually loaded in a manner that provides optimal storage capacity. However, this often means the tool access sequence is different from the sequence of machining operations. The distance from the tool to the spindle has a significant influence on how long the tool change takes.
To reduce these idle times, workpiece details to be optimised can be selected from pallet management and transferred to the cloud. Both tool change times and tool idle times are then analysed and evaluated in view of the sorting order, providing the shortest idle times for the given workpiece and the machining operation. The CNC program for re-sorting the tool magazine is then generated in the cloud and provided to the machine.
Integrating Downstream Machining
Another current project is Industry 4.0 metal additive manufacturing. The experts are working on a cost-effective process machine tool, providing high material application rates in an industrial environment supplemented by downstream machining.
The Industry 4.0 idea is to use this technology for making additions to the component whilst integrating downstream machining operations in order to achieve the required drawing specifications. As with CBC, the goal is to find solutions for relevant applications in series production for the general machine and automotive industry.
Other developments of new business and technologies development division focus on light-weight construction. The demand for lighter vehicles inevitably requires the use of light metals and carbon fibre-based plastics, where research is underway on the most appropriate machining processes.
Flexible integration into existing production systems should be a focus for manufacturers.
Research is underway for the most appropriate Industry 4.0 machining processes in light-weight automotive construction.
To reduce idle times Industry 4.0, workpiece details can be selected from pallet management and transferred to the cloud.
Due to flexible complete machining on a 5-axis machining centre, costs can be reduced.
Complete machining solutions at component level are improving cost-efficiency for the aerospace industry. By Lim Gan Shu, Southeast Asia marketing manager, Walter AG
Although the topic is not new, it appears as a new item on the agenda on a daily basis: The demands made on manufacturers in the aviation and aerospace industry are becoming increasingly more demanding and complex. And what applies to production businesses, also applies to the machining industry that provides them with the tools they require.
In order to be more cost-efficient, manufacturers need to not only use tools that perform with a long tool life, but also continuously optimise their machining solutions and processes. In this area in particular, Walter provides support for its aerospace customers.
Creating Complete Solutions
The goal is to create complete solutions that address the complexity of the task and help to increase productivity and cost-efficiency.
“Today, customers expect their tool supplier to have a high level of expertise in all key operations that are carried out using its tools. This reduces the increasing cost pressure and compensates for the loss of expertise which arises as a result of outsourcing a large number of tasks.”, explained Thomas Schaarschmidt, director business and application development at Walter.
This means that, in addition to the tools required for the relevant machining solutions and the associated comprehensive service, suppliers also have a recycling and reconditioning program.
Technical support is provided, and simple order processing is integrated into the customer’s workflows. The supplier programs the machining systems (or helps the user’s staff to do so) and trains the customer’s employees, among other requirements that are neded.
Crucial Beneficial Effects
In addition, the tool specialist develops complete machining concepts, including all process steps which arise during the production of a component. These concepts are individually tailored to the customer’s needs and contain detailed recommendations regarding which tools are used in which step.
Mr Schaarschmidt said, “We have taken our customers’ list of requirements and developed it further. In other words, we have been systematically building on the comprehensive expertise that our customers need to take on the problems and challenges associated with the production of their components. We make this expertise and the discoveries which result for the production process available to our customers. We are thereby actively helping them to use our tools as efficiently, and as cost-effectively, as possible.”
First, Mr Schaarschmidt’s team defined specific components that are frequently used in the aerospace industry: Structural parts made from titanium aluminium alloys, for example, or engine and landing gear components. Complete machining solutions for these components are then developed in close collaboration with technology partners from the sector: Key customers, machinery and software manufacturers, suppliers, universities and research institutes.
Practical Development
“For every component for which we develop a machining solution together with the customer, we analyse the features and look at which and how many variations exist for each component. Then we map the entire process chain as it is implemented at the customer, in-house or at technology partners. This means that we know every detail that is relevant for machining the customer component,” said Mr Schaarschmidt.
In the next step, a roadmap is created that defines which steps are to be taken to the finished solution. The specialists identify what they can do where, which processes they have already mastered, where there is need for development and how this should be covered most effectively and in the quickest way possible.
The creation of machining concepts involves tool specialists who bring their expertise in machining turning, drilling, threading or milling using a wide range of different materials. The process also involves component experts who know which challenges associated with the manufacture of specific components need to be overcome.
To enable them to tailor their solutions as closely as possible to the specific requirements of the user, the company’s component managers visit their customers on a regular basis.
“Our component managers are deeply involved in the topic; they speak the language of our customers and know exactly where the problem areas lie,” explains Mr Schaarschmidt.
Their task is to keep up to date with what the users of the cutting tools are currently doing, and what optimisation measures or open topics they are looking at. They also gather feedback on recommended machining solutions.
A Competitive Advantage
The solutions that Mr Schaarschmidt’s team develops with customers have the purpose of creating competitive advantages for customers. It is therefore not uncommon for one machining concept to include hundreds of pieces of detailed information, machining steps or more. This includes numerous variant-specific machining solutions for every component.
Mr Schaarschmidt stated that his team’s goal is to offer a complete solution for 80 percent of the different variants of a component—all documented, partly standardised and accessible to specialists at all times.
The result: recommendations of which tools, machining parameters and processes can be used to produce a certain component with costs. This information is passed on to their customers via technology days together with technology partners, via roadshows, using training videos or animations on YouTube and, in the future—to deal with the trend in digitalisation—via the company’s homepage and augmented reality.
Knowledge about future products and requirements also flows into the development processes.Mr Schaarschmidt explains the benefits for customers:
“Forward-looking planning and development enables us to offer our customers a completely new type of machining solution, often right at the start of production of a new product, which is precisely tailored to them.
He adds that his team is able to support their customers with new component-specific cutting material solutions with immediately. Along with reduced start-up costs, the time between development and series production (time-to-market) is considerably accelerated and that this has a positive impact on cost-effectiveness.
Porcupine milling cutter for roughing titanium alloys
Landing gear mounts are complex structural components that are situated horizontally in the wing structure above the landing gear. These elements connect the wing and the landing gear and act as a shock absorber in conjunction with the main cylinder of the landing gear.
Wing ribs are structural components inside the wing. Together with the longerons, they form the frame for the wing skin. Wing ribs are predominantly manufactured from aluminium wrought alloys. These are light, have a high load-bearing capacity and are extremely robust.
Innovation in transmission design means that today’s transmissions are generally getting smaller, while simultaneously offering more gear ratios. In what ways have machining automotive gears improved? By Markus Isgro, marketing communications, Emag
The production of a large volume of parts with extremely high quality has been a key feature in the production of automotive transmissions for decades. Developments in both the marketplace and technology, however, are continuing to change production at a very fast pace. For example, the demand for cars has been rising. This Turning And Grinding Solutions increase in quantity is pushing the production volume of gears even higher.
At the same time, the competition from new market participants in Asia is intensifying. What can the transmission builders of OEMs and suppliers do in their production areas to address these developments?
Multifunctional machines that perform an array of hard machining processes on the transmission components in succession are able to provide such a solution. Emag, with expertise in turning and grinding, have provided an option called the VLC 200 GT. This machine was developed for the chuck machining of automotive gears.
Innovation In-Transmission Design
The automobile industry is continuing to spend more money on research, and annual increases of between seven and eight percent in this area have long since become standard. OEMs and suppliers in Germany alone recorded more than 34 billion euros (US$36.5 million) in development expenses in the past year, according to a study by the German Association of the Automotive Industry.
One of the main focal points of this dynamic innovation is transmission design. Today’s transmissions are generally becoming smaller (and therefore lighter), but can simultaneously offer more gear ratios and therefore have more gears and gearing components. This produces optimum speed ranges and reduces fuel consumption.
Each individual gear must be manufactured extremely quickly and very precisely. Given the high unit volumes, the production technology is virtually always a concern for production planners. They try to find solutions that reduce processing time and unit costs, while still continuing to increase the quality of the parts.
Nearly 20 years ago, the first pick-up machine for the combined turning and grinding machining of chucked parts was developed. Its key feature was the combination of the two machining processes in rapid alternation, based on the shape of the workpiece and the quality required.
Building on this, the VLC 200 GT has focused on enhancing productivity, especially in the machining of automotive gears. Guido Hegener, managing director of Emag, explained the approach: “The high unit volume and quality requirements of gears make them ideally suited to our approach.”
Complete Process, Including Dressing
To start, the machine is loaded at high speed by the integrated pick-up spindle. Once the spindle with the part reaches its machining position, the process starts with hard pre-turning of the shoulder and the bore hole in quick succession.
Only a few micrometres of material are then left to be removed from the gear. That means the subsequent grinding process, using either aluminum oxide or CBN grinding wheels, takes significantly less time.
Meanwhile, the machining quality also benefits from the combination of turning and grinding: when there is only a small amount of material remaining to be ground away after turning, the specifications for the grinding wheel can be based more precisely on the end quality required. As a result, surfaces with an average peak-to-valley height Rz of less than 1.6 micrometres can be created.
In addition, this multifunctional technology offers users a multitude of possibilities, such as internal and external grinding spindles, scroll-free turning tools, block tool holders, and a 12-station tool turret, which can all be installed as required.
Tool Cost Savings
There is an additional advantage in terms of tool costs because during this process the grinding wheel wears down more slowly and therefore does not need to be dressed as often. When it does need dressing, the machine has a separate diamond-coated dressing roll designed specifically for this. To ensure sustained process reliability and high machining quality, the integrated measuring pin is used to check the diameter and length of the clamped component at the end of the process.
Operator comfort and ease of access were also important priorities, so large doors allow easy access to the machining area. The tools and clamping devices are easily accessible and can be changed quickly and conveniently.
Automated Option
With a small footprint and the ability to flexibly integrate into interlinked factory systems, the machine can be incorporated into a plant’s production system with the aid of a variety of automation systems.
One option for this is the TrackMotion system. This automation system handles the transportation from machine to machine with functions such as part gripping, positioning, and flipping of the workpiece.
“On the other hand, there is also the option of using the machine as a stand-alone machine with simple O-belt automation. This is an appealing alternative for many customers in the Asian markets especially,” Mr Hegener added.
The VLC 200 GT uses a variety of process combinations for the hard machining of checked components.
In order to increase the productivity of the milling process in a die and mould company, one cannot concentrate only on the high-performance Faster Machining centres. Contributed by Haimer
Die and mould company Langer GmbH & Co found out that proper usage of tool holders could reduce the total Faster Machining times on several applications almost in half.
The company, located in Illmensee, 17 km north of Lake Constance in Germany, is a die and mould producer with approximately 140 employees. The services that they offer include the development and production of prototypes of serial tools for injection die moulding, up to the sampling of pre-series and small series production.
Injection Die Moulding
The die and mould department’s 60 employees focus on finishing the tools for injection die moulding in the quickest possible time while reaching the high-quality requirements of the automotive industry.
The data to be transcribed out of the design department into high-quality tools out of aluminium-wrought alloy or profile steel of type 2312 and 2767 is the job of the company’s NC Machining team. Their team leader, Jörg Lehmann explains that along with the machines, tool holders and tools are the main factors that affect machining times. In his department, there are six modern, three to five-axis machining centres from DMG, Mikron and Hermle.
Langer was not satisfied with the current shrink fit chucks they were using, however. After a few shrink cycles, those shrink fit chucks were no longer giving the required clamping forces.
Theory And Application
An important feature of shrink fit chucks is a tight-fitting bore that holds the tool in the longest range possible. The entry chamfer of the shrink fit chuck plays a very important role, as this is where the protruding length and the rigidity of the tool are decided. Shrink fit chucks from various producers allow the entry chamfer to be five to 10 mm long.
As a result, there is often no clamping in this position, and the protruding length of the tool is unnecessarily increased. This can also similarly happen on the back end of the fit, where the chuck often has too much material turned out. There are also no clamping forces that hold the tool here. Due to these factors, the range of the fit is relatively short.
Mr Lehmann Faster Machining tried the chucks from Haimer and shared his observations. “The chucks offer a lot of mass in the upper range, which reduces vibrations and the slim form in the lower range enables machining in tight contours,” Mr Lehmann said.
Made For Mould & Die
The company Faster Machining developed the Power Mini Shrink Chuck especially for the requirements of five-axis milling in the mould and die industry, where they are suitable due to their special combination of a slim tip and strong base.
A prominent feature of the chuck is the slim outside three-degree angle contour, which is the draft angle that is used in injection die moulding. The chuck has a strengthened contour at the bottom end of the chuck. Due to this, the shrink fit chuck can cut in deep mould cavities but is rigid enough to absorb heavy side forces occurring at five-axis machining.
“We can go for much higher cutting values and save time with pre-work, for example, groove milling in steel. Here we use a two mm diameter ball cutter to pre-finish first to 1/10 of a millimetre. We can reach the desired result in one finishing pass. The machining time is then reduced by up to 50 percent,” said Mr Lehmann.
Optimal Surface Finishing
Faster Machining Mould and die makers often use high rpm in order to achieve optimal surface finishes. When milling in deep cavities or pockets however, it is important that the chips are properly washed away. That works only when the coolant stream hits the right point with high pressure.
Haimer recognised this problem in its production. The company’s previous solution was the Cool Jet System, which integrated coolant bores into shrink fit chucks and other tool holders. Through the use of two or three nozzles, the coolant is transported directly onto the tool cutter.
The company used this approach to develop the Cool Flash system, which can be integrated into shrink fit chucks. At the top of the shrink chuck, a disc is inserted onto the Cool Jet bores, which has a small ring gap left open with slots opposite to the tool shaft. The coolant is not fed through points but is transferred in a ring form to the cutter and can lie around the tool like a coating. The coolant then clings and slides on the miller shaft, also at high rpm, as a coating over the chip flute to the cutting edge. The shrinking process is not an issue and the system does not involve any assembly.
Faster Machining High-Speed Cutting
In order to have high-quality finishing results, the milling cutter must be cooled externally to flush chips out of the way, but many milling cutters may not have an internal bore for the coolant due to stability reasons.
In Langer’s testing of the new system alongside the typical flush cooling from the coolant hose, Mr Lehmann said that the system has allowed for speeds of 20,000 rpm, compared to previous tests which started to have wide dispersion at 6,000 rpm.
“Where we used to have to decrease feed rates by critical operations such as pocket milling, we can now work in normal speeds. There aren’t any chips that get stuck and the millers do not break. In addition to the Faster Machining increased process stability, we also save on coolant usage compared to the flush cooling from outside,” said Mr Lehmann.
The proper shrink fit machine is also required for the shrink fit chucks. An inductive shrink fit machine can be adjusted to the length and diameter of the chuck. Due to this only the clamping range of the chuck is heated, which considerably reduces the cooling time, among other things.
From left to right: Joerg Lehmann, team leader NC machining, Langer,and Oliver Lechner, Haimer.
The finishing was made in one pass and met all quality requirements.
The Cool Flash System enabled cooling and chip-removing effect up to 20,000 rpm.
Many CNC parts manufacturers, as well as production and job shops, could reduce their overall production costs 15 percent or more by leveraging existing CAM technology that is readily available. By Stas Mylek, applications advisor, CNC Software Optimal Material Removal
Typically, production cost centres are Optimal Material Removal often evaluated independently, whether they be tool costs, raw materials, capital equipment, manpower, or production costs. However, incremental savings in each typically do not add up to significant gains overall.
Our Optimal Material Removal contention is that the areas of cutting tools, CAM, and production, particularly the newer toolpath technologies, along with machine capabilities and investment, be looked at concurrently with the goal of optimisation as they relate to each other. What we are looking for is hitting the optimised sweet spot of all three, referred to as machining effectiveness, to gain significant production cost savings.
Machining Effectiveness
Adoption of this approach pursues a very simple formula:
Select optimal cutting tools for the part. This will often be high-quality Optimal Material Removal carbide, but can be ceramic, insert tooling, or any other type of tool. The key is optimising to the chosen tool(s).
Based on the cutting tool manufacturer’s recommendations, import the correct parameters for consistent chip load machining into toolpaths having this capability.
Optimise the cut parameters, if necessary, to match the full capabilities of the machine the job is running on.
Repeat for every toolpath process you create using CAD/CAM software where the same tools, material, and machine are used.
Everything begins with the tool, and the calibre and quality of carbide, advances in new ceramics, new grades, coatings, tool geometries, and the design engineering going into today’s tools are far different and more capable today than what was available just five years ago. Full slotting tools capable of going up to four times deeper in not only hardened steels and stainless, but super alloys was unheard of even a short time ago.
Today, it is much more prevalent. These tools promise huge material removal gains, yet also require exact adherence to recommended cut conditions and chip load to gain optimal performance and predictable tool life to address machining effectiveness.
New Toolpath Strategies
Optimal material removal and cutting tool performance occur when CNC machines are programmed using newer, readily available CAD/CAM software technology (Mastercam’s Dynamic Motion technology is one example). This technology continually maintains the cutting tool manufacturer’s recommended cut conditions and chip load, regardless of part geometry. Significantly higher material removal rates, with more predictable and extended tool life, translates into the higher reductions in cycles times and production costs necessary for achieving machining effectiveness.
And the machining effectiveness of the newer toolpath strategies are not limited to just the new breed of cutting tools; improved material removal rates and tool life can be realised with virtually any tool since these newer toolpath strategies are based on consistent cut conditions.
Over the better part of a decade, since these new toolpath strategies have been available, manufacturers of all types typically report CNC machine cycle time reductions for their roughing operations of between 25 to 70 percent—sometimes much more. Recently, a manufacturer reported that apart with a machine cycle of 32 minutes had been reduced to 12 minutes by implementing a machining effectiveness mindset.
Matching Machining Capabilities
Optimal Material Removal Machining effectiveness gets another cost savings to boost when you begin to match machine capabilities to cutting tool performance potential and toolpath strategy.
With a toolpath that always keeps the tool in a safe, cutting condition and does not violate the tool manufacturer’s recommended chip load specs, CNC programmers can apply different methodologies. On faster machines where work holding might be lighter and cutting tool selection more traditional, users might opt for a higher feed rate and small step-over approach to maximise material removal rate and to lower cycle time.
If set up is on a higher horsepower machine, that tops out on feed rate yet where the work holding can be locked down, a company might run the newer, full slotting-capable tools. Matching tool to machine to cutting tool capability, they could run heavy step-overs of 65 to 80 percent at 2x to 3xD or more and see material removal gains increase well beyond 70 to 75 percent over traditional toolpath strategies, resulting in a huge production cost savings. All this is feasible once companies put machining effectiveness into practice.
Time To Adopt
However, adoption of these newer strategies and embracing a machining effectiveness mindset has been slow, yet there are signs they are finally beginning to take hold. Straw polls of CAD/CAM users and industry event attendees indicate that 30-40 percent of programmer/machinists are using these new toolpath strategies with increasing regularity.
But what about the other 60 percent of CAD/CAM users? They frequently report not looking into it because, honestly, they have not had the time, nor given approval to do so.
Exactly how much time are we talking about to implement a demonstrably better cost cutting methodology? Actually, very little. Tool manufacturers’ recommended cut parameters are often provided in available tool libraries and easily imported directly into toolpath operations of the CAD/CAM system when selecting a tool and material. Adjustments are made based on tool capabilities such as whether to use a small or large step-over approach and what limits need to be applied to depth cuts based on the type of tool.
Utilising Your Machine’s Potential
Machine limits relative to spindle speed, feed rate, and horsepower are also considered prior to processing the program. Using toolpaths that maintain consistent chip load and safe cutting conditions, it is simply a matter of taking the program out onto the machine. Machine performance is validated relative to holding the programmed feed rate, ensuring the right workholding setup is in place for strategy, and that spindle load is maintained under the set requirements.
Once the program is running on the machine, it may be necessary to make some minor adjustments to toolpath parameters to make sure the software is taking full advantage of the machine’s capabilities.
Conversely, some machine controller settings may need adjustment to take full advantage of the toolpath. Very often, cutting tool vendors, CAD/CAM resellers, and technical specialists are happy to help you maximise performance and prove out the application.
Cutting Chunks Off A Cycle
Once the process and strategy is validated, the approach can be applied every time that tool is used to machine a part made from that material. Benefits can be seen in everything from simple to extremely complex, aerospace and thin wall parts, and more easily machined materials to super-alloys.
For example, a job shop recently took six hours off of a 24-hour cycle for an aerospace part by adopting machining effectiveness methodology. This conversion paid for itself immediately after the first part was produced. Better still, the company had a contract to make six more of them. So the benefits multiplied quickly.
The bottom line is that many manufacturers in many industries are operating far less efficiently than they could be and leaving money—lots of it—on the table by not optimising cutting tool, toolpath, and machine performance and viewing them in an integrated relationship. Cutting costs is necessary to compete and remain profitable. However, there’s a lost opportunity cost for companies, and possibly for entire manufacturing sectors, that don’t leverage everything they can get from inter-related technologies.
Significant Gains
By aiming at that optimised sweet spot called machining effectiveness, the gains company-wide or even for industry, can be significant. By that, I mean millions.
This seems like a pretty outrageous claim. Can it be justified? I think so. Cutting tool manufacturers are very confident that their best route to justify the benefit of higher quality and cutting tool performance is to show new users improved productivity.
For example, Tom Raun, national milling product manager of Iscar Cutting Tools, maintains that the cost of the tool is really insignificant compared to the benefit of improved machine cycles. Cutting tools amount to about three percent of a typical CNC shop’s total costs. If tool life can be doubled, then that ROI amounts to less than 1.5 percent of the shop’s total costs for cutting tools. Even so, if a shop realises it can reduce its tooling costs by a million dollars by making a simple purchasing decision, it will jump on that opportunity in a heartbeat.
On the other hand, experience has Raun convinced that a 20 percent improvement in material removal efficiency can yield a 15 percent improvement in manufacturing costs per unit.
Think about it: A shop with US$100 million in sales could realise a US$15 million gain by making an average 20 percent across-the-board improvement in machine cycles using mostly existing equipment and software. If parts manufacturers in just the automotive, aerospace, and energy industries embraced this idea, the savings would easily be billions.
Embracing The Effective Viewpoint
So why are we not doing it? It all comes down to a change in viewpoint, finding the time to save time, and making a commitment to get better. Production deadlines are always looming and we all get comfortable with current processes, whether we’re managers or programmers. It takes valuable time and resources to test and evaluate new technologies and methods, or to experiment with the outer boundaries of what is possible.
Yet, with the potential payback and production costs savings of 15 to 25 percent or more, isn’t it worth it? The pressure of a tight deadline could be loosened by the opportunity of getting jobs done faster and with fewer issues or setbacks.
What is needed is a little bit of planning and optimisation targeting better machining effectiveness up-front. This can lessen the impact of tight deadlines as well as downtime incurred due to lack of efficiency. It is not uncommon to find initiatives of this sort yielding total manufacturing process cost reductions of 15 to 25 percent or more.
Savings of this magnitude could be used to achieve such worthy objectives as improving profits, capturing more business, and doing the modest amount of training required for more robust workforce development and continuous improvement.
People who are in charge of the day-to-day operations at machine shops are frequently under too many pressures to take the lead in initiating the sort of changes that are required. That sense of urgency also needs to come from the top.
Manufacturers need to evaluate their tool efficiency to achieve maximum output.
Cost breakdown of the manufacturing process.
Stas Mylek believes the right tools are essential in increasing revenue for manufacturers.
