A manufacturer of personal care products has saved money by switching to a low-cost computerised numerical control (CNC) router that can produce point of purchase displays internally. The manufacturer employed contractors to produce displays but there were delays in getting new designs to retailers and the cost of producing them was continually rising. The company made the decision to create its own displays and searched for an inexpensive, yet easy-to-use router that had the capability to produce plastic and wood components to high levels of accuracy.
It opted for the Isel router, which has allowed the company to design and create new display designs in a single day. Isel's router has features readily found in more expensive machines such as ball screws and servo motors. This manufacturer is saving money on its outgoings and can now turn on immediately to meet the ever-changing design demands of the retail market. Ball screws have a few key advantages over racks: they don't have the 'play' or the requirement for adjustments that racks require, do not wear as easily and are far less likely to leave debris in the mechanism, a cause of skipping and errant motion.
Servo motors, unlike stepper motors, do not lose position, cannot skip steps and are also better for 3D applications as they can change speed 'on the fly' without losing position. The company's products are shipped to retailers with displays made of acrylic sheets that contain the product. The displays range from approximately 220mm high by 200mm wide and 200mm deep, to as much as 600mm high by 300mm wide and 200mm deep, with either two or three tiers of shelves. The product is placed loose in the shelves, which are tilted backwards slightly to keep them secure.
The shelves are held to the walls with acrylic solvents. The company frequently develops different styles of displays in order to accommodate a new product or promotion; subcontractors built a substantial portion of these in the past. The disadvantage with this strategy was that a considerable amount of back-and-forth effort was necessary in order to communicate the company's specific concept for the display.
With the rising cost of production, the process of going from prototype to finished product was proving inefficient as well as expensive. The company set out to look for CNC routers; however, the ones that it saw were either too expensive, very complicated machines, or on the other hand, inexpensive routers. The Isel machine possesses a number of features that are said to deliver accuracy to a level that has previously only been attainable at a much higher price.
Ball screws are provided on all three axes, providing smooth motion, a high level of accuracy and repeatability, plus minimal maintenance. A closed-loop servo control system provides constant position feedback, higher power and smooth continuous motion, which eliminates the possibility of losing position in the middle section. The machine includes a heavy steel ground stress-relieved base and an aluminium T-slot table that can be converted to a vacuum table by installing a vacuum table accessory kit.
The machine comes fully assembled and includes a CNC G-code interface. It is available in three sizes with work envelopes of 750mm by 600mm, 1,250 by 1,200mm and 1,250 by 2,400mm. Each of these models provides a repeatability of 0.025mm, a resolution of 0.005mm and a maximum speed of 6,350mm per minute. A wide range of optional equipment is offered including a laser scanning module, CNC lathe attachment, vacuum blower and a fourth-axis rotary table.
The resultant situation is that the company's designer creates a CAD drawing of a new display then graphically nests the individual pieces required to make the display onto a foot acrylic sheet and saves the resulting drawing onto a CD. The CNC operator generates toolpaths, makes adjustments to compensate for the thickness of the sheet and creates a CNC program for producing the parts. The operator loads a new sheet onto the router, secures it with a vacuum clamp to the table, uploads the program into the machine control and, with a click of the mouse, starts the machine.
The machine establishes the zero point for the z-axis and then runs by itself for 30 to 120 minutes, producing enough parts for as many displays as is possible to nest onto an acrylic sheet. When the machining operation is finished, the pieces are removed and they apply a torch to flame the cut edges to produce a glossy finish. These are delivered to the assembly department where operators put them together by applying acrylic solvent with a syringe.
The accuracy of cutting enabled them to develop a tab and slot construction in some of the displays, which overcame some of the difficulties that assemblers were having in alignment of walls and partitions, providing improved positioning for high-precision line bending. The time required to respond to market trends by creating new displays has been cut to a fraction of its original duration. On several occasions, an idea for a new display has been built and assembled by the end of the day. Building displays in-house also makes it much easier for companies to respond to special requests from customers.
