Increased versatility and lower price points are pushing the spread of CNC machines beyond just the large woodworking companies and into the smaller and mid-sized manufacturing operations.
|Advancements in software, 4- and 5-axis capabilities, and other technological progressions are birthing faster and more versatile machines. Photo courtesy of Delmac Machinery Group|
More flexible, as well as more affordable machines, are making the use of CNC machining centers much more prominent in the woodworking industry. Wood & Wood Products talked to machinery experts to gauge their thoughts on where CNC machining centers are at now, as well as where they are going in the future.
“In today’s turbulent economic times, now more than ever, CNC automation makes sense,” says Adam Sebran, North American sales manager for MultiCam Inc. “Automating the cutting process sends profits to your bottom line. Our customers want to make accurate parts faster, with less waste, less labor and shorter lead times. CNC automation achieves these cost saving goals.”
Advancements in software, 4- and 5-axis capabilities, and other technological progressions are birthing faster and more versatile machinery.
“CNC router/machining centers are the heart and soul for most factories,” says Rob Howell, business manager, Hi Tech Panel Division for SCM Group USA Inc. “Five-axis routers are becoming more affordable and are the most flexible machines on the market. They allow the customer complete flexibility without the need of expensive aggregates. These flexible machines can have both 3- and 5-axis routers on the same machine, which provides the best of both worlds.”
“Some of the cutting edge innovations include 5-axis heads, moulding units, expanded range of aggregates and the ability to have the pods and rails electronically positioned, which takes the potential for human error out of the equation,” says Cesare Magnani, North American product manager for Biesse America. “In the nesting environment, the ability to have a dual zone machine (20 foot) that can nest full sheets while providing a load/unload time of zero, has drastically changed the throughput of nested-based machines while utilizing a single operator.”
“Four- and 5-axis capability, combined with proper tooling, gives CNC machines the flexibility to perform nearly any machining operation,” says Bill Blackmon, Busellato product manager for Delmac Machinery Group. “This technology is not new, but the programming and control software have advanced to make these machines more feasible for smaller companies to implement. Programming is now an extension of product design rather than a separate department with its own staff. On another front, new loading and unloading systems for nested-based machining centers continue to raise the productivity of these one-man cells.”
“Features like increased tool change capacity, Flex-5 aggregates and full interpolating 5-axis capabilities allow end-users to take on more complexity, with fewer limitations,” says David McFarland, senior manager of CNC at Stiles Machinery Inc. “More powerful, ‘on-board’ software packages are helping management to offer a greater level of autonomy to the shop floor.”
“Most mechanical advancements have been made in the area of speed,” says Larry Tolbert, regional sales representative for Solid Wood Systems Inc. “Faster axis acceleration/deceleration, combined with higher rapid speeds, has increased overall performance.”
Ken Susnjara, chairman/CEO of Thermwood Corp., says more advanced tooling systems have had a positive effect on nested-based machines. “Modern nested-based machines offer sophisticated tool management systems,” he says. “They track the use of each tool and alert the operator when one is getting dull. They can automatically switch from one tool to another when one tool gets dull. They are managed using a simple graphic interface that makes tooling status clear. These systems can even automatically optimize tool placement for a program.”
|CNC machines are becoming more affordable for both large- and small-size shops. Photo courtesy of Solid Wood Systems Inc.|
Not Just for the Big Dogs
Recent developments have also made it possible for smaller shops to get in on the CNC action in the form of lower price points.
“I believe that for the smaller- to medium-sized end users, the most advantageous recent development would be the evolution of lower price point machines that offer most of the flexibility and features of higher-end, higher-volume machines at a much lower price point, but now aren’t just ‘throw-a-ways’ or ‘design tools,’” says Tom Flowers, sales manager for CR Onsrud Inc. “This quickly growing new class of machines can now provide many of the same advantages of flexibility to a smaller shop as the larger machines offer to larger shops, but at a much lower complete package price point, and at an acceptable compromise in throughput and speed.”
“The advancements of affordable laser technology, plasma devices, routing configurations and tangential knife setups have allowed users the versatility of one machine to perform the work of machines costing more than four times as much,” adds Mike Seegar, sales and marketing manager for ShopSabre CNC.
“We expect to see a continued migration of technology towards a lower entry point for CNC machines,” says McFarland. “Prospective CNC users will have to take caution in specifying a machine that has not only the appropriate amount of flexibility, but also the correct design for durability.”
“We see feature rich, lower cost solutions becoming more and more popular,” adds Sebran. “Buyers are looking for economy and a way to automate their shops at lower introductory prices.”
More Than Wood
Materials other than wood can pose challenges to CNC machinery, but many of the new machines have dealt with this dilemma through adjusted spindle rpm rates and feed rates.
“Our developers try to accommodate the widest range of materials possible by allowing our spindles to run from a low rpm (600) to a high rpm (24,000),” says Howell. “We do have special applications that would allow for higher rpms, if needed.”
“Along with solid wood and wood composites, plastics and non-ferrous metals are becoming more commonly requested by the end-user,” says Blackmon. “The quality required in the finished product dictates the tooling, rpm and feed rate (chip load) to be achieved during machining. Many plastics and composites require much lower rpm than typical wood-based materials and, at lower rpm, spindles do not produce full power. The bottom line is to specify a spindle in the 12 to 16 horsepower range when a variety of materials will be machined.”
Some of these substrates can affect other specific components. Various hold-down systems, for instance, will work better with certain substrates more than others.
“There are four basic hold-down systems for the CNC machine: vacuum tables, vacuum pods, pneumatic clamps and roller hold-down,” says Blackmon. “For vacuum table systems, do not skimp on the vacuum pump. Plastics and plywood substrates are not always flat and more air flow is often required to get these materials to hold satisfactorily. Pod systems are very flexible with quick setup. The substrate must be rigid enough not to flex or sag between the pods, if precise machining depth is required. Pneumatic clamps are a must for heavy machining of thick, narrow stock, such as door and window components. A reliable setup and positioning system is important. Roller hold-down is useful for high production of low finish-quality plywood components and not very common in today’s custom environments.”
“Holding hardwood parts such as door stiles and rails, requires high-pressure, low volume vacuum pods and pump systems,” says Sebran. “Flat panel processing of plywood, melamine and plastics requires medium pressure, high volume flow-through spoilboards and pump systems. Many router manufacturers attempt to use one type of vacuum system for both applications. This is bound to produce poor results for one or the other application.”
“Typically, flat-table CNC machining centers are more efficient for custom cabinetry, while pod-and-rail machines are better for solid wood applications because of the quicker changeover and the ability to clamp down parts where the vacuum will not hold down parts,” says Magnani. “In today’s evolving market, there are convertible solutions that give the customer the best of both worlds. This solution starts life as a pod-and-rail machine and in a matter of minutes, can become a highly productive nesting machine.”
In addition to wood, plastics and non-ferrous metals are becoming increasingly used by the end-user, resulting in more flexible machines. Photo courtesy of Biesse America
The Future of CNC
New developments in CNC are already on the horizon. Those interviewed seem to agree that better integrated and faster machines will be on shop floors in the near future.
“[I foresee in the future] CNC machines with more integrated loading and unloading systems,” says David Steranko, president of Anderson America.
“I expect to see further integration between CAD programs and the CAM software for the machine,” says Tolbert. “This will make the connection between product development and actual workpiece production even easier. I think we will also see further advancements in the flexibility of these machining centers, allowing more operations to be completed on the workpiece without repositioning the part, with new designs in workpiece holding devices and automatic loading/unloading options.”
“Future developments we will most likely see will include faster and more powerful drive systems with even greater accuracy,” adds Seegar. “Structures will also be improved to handle the advancements in drive systems.”
“The target for machine manufacturers for the coming years will be energy efficiency, increased productivity, zero setup time, reduced maintenance and reduced cost of ownership,” says Magnani.
“One of the most exciting developments, I see in the future is the growth of CNC routers into markets and applications that just a few years ago nobody would have considered a router for,” says Flowers. “These machines are so incredibly flexible, and are becoming so easy to use, that I see them becoming to a manufacturer much what the PC or the printer is to the workplace now. In the same way that you wouldn’t try to compete in an office without computers or a printer, manufacturers are accepting that CNC routers are also necessary in order to compete. This is what is bringing the price down for everybody, while the machines get better and better.”
CNC For the Smaller Shop
For a smaller shop, making the move to CNC equipment involves different considerations than a larger shop may have. Should one use a multi-function machine or a dedicated machine? What should be expected in regards to performance? Will the machine be in use enough to justify the price tag? A smaller shop most likely also has a smaller budget, making these questions even more significant.
“The important thing to appreciate is that with nested-based operations, it is the flexibility and multifaceted cutting and machining capabilities of the CNC tool that make the approach work,” says Ted Hall, president of ShopBot Tools Inc. “For cell-based operations, adding the flexibility, configurability and repeatability of CNC can enhance productivity beyond what is available with stationary or manual power tools. The key in both cases is the configurability and flexibility of the CNC robotic tool. Opt for a CNC that is easy to set up, easy for all operators to understand and use, and straightforward to change over or configure for the next task or process.”
“The primary advantages of a multi-function machine are the reduced amount of labor and processing time,” says Phil Polston, sales manager for Weeke Vantech routers at Stiles Machinery Inc. “Each time a part is moved from one machine to another it adds cost that can never be recouped. Nested-based manufacturing can take the place of two to four machines. In determining when a shop should choose one manufacturing method over another, the number of sheets and operations performed should be the first items considered.
“A con would be the misconception that a machine not in operation all day is a wasted investment,” Polston adds. “This is a concern for many small shops who are considering the addition of a router to their business. Traditional manufacturing concepts conveyed that machines should be operating at all times for maximum efficiency, but routers bring a new mindset. In a few hours a router can produce what traditionally took three or four shop employees two days to produce. Efficiency is gained, even with the machine is not in constant operation.”
According to Polston, patience is an important virtue when bringing CNC equipment into the shop. “First, there should be some expectation of growing pains and an understanding that new technology and processes cannot be successfully implemented in one or two days,” he says. “This is a good time to partner with a company that has experts to assist you. It is important to look at what hours a supplier provides technical help and how much training and education that company will provide. Exercise patience and realize up front that change for the better is not without its challenges. Once there is a gain in confidence, six to eight times the work you did using traditional methods can be achieved. The greatest hurdle is usually in learning a new process and trusting your decisions. Most small companies investing in their first CNC machine will start to gain that comfort level around the 90-day mark.”
Hall says that for any size company buying a CNC, there are certain factors that should always be taken into consideration. “An important thing to remember when considering purchasing any CNC is the commitment that is involved,” he says. “It takes time to learn the software, time to learn proper dust collection and hold-down techniques and time to train new employees. A CNC can only do what its operator tells it to do. Although, in many cases, a CNC can perform tasks more accurately and efficiently than a human employee, it still requires regular maintenance and a dedicated operator who is willing to learn the ins and outs of the machine. Do the proper research to determine if a CNC is right for your shop, and if you decide to purchase one, get to know your chosen manufacturer’s sales and support staff.”
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