It’s not news that in Australia; the nesting of cabinet parts on CNC machines is practiced by a very high percentage of firms. Some say this figure is well over ninety percent. Obviously this puts those companies in direct competition with over ninety percent of the rest of the industry where the costs and production is the same as everyone else’s. Ask any business consultant and they will tell you that this is not the best position to be in. They will tell you that specialisation; where you can charge a premium for services others cannot provide, is a better solution. However; as the manufacture of cabinets for kitchens; bathrooms and laundries and even living areas is a high proportion of the overall furniture industry, many manufacturers find themselves manufacturing to the lowest possible production cost and nesting provides just that. Unfortunately this often translates to low profits, especially when other businesses in your local area produce exactly the way you do…and you end up selling on price.
And so if you are a nesting company, it’s always a good idea to be on top of the game and the experience gained by other businesses that work the way you do could help. The following case study was first published in the German publication HOB Holzbearbeitung December 2017 with the kind permission of Dr. Michael Hobohm and provided as a press release by the Leitz Group at Holz Handwerk this year. It looks at the Mayer Wood Products company located in Bad Säckingen, Germany and in particular; the machines and tools they use to process cabinet parts. Mayer started as a one-man-operation in 1993 and today has eleven employees. It’s a business similar in many respects to thousands of Australian companies and faces the same issues. The company has until 2016 produced with a beam saw but recently invested in some new machinery including a Holz-Her CNC nesting machine and a Biesse ‘Skipper’ vertical CNC drilling machine. They also made an investment in Leitz diamond tools.
At Mayer Wood Products the purchase of new equipment became necessary because their panel saw had reached its production limits. The company was also looking to launch into a net-based business with online trading, initially cutting boards into components with and without edging. Managing Director Berthold Mayer says “Later, ready-made furniture will be added.” As their equipment and expertise grew, so did their range of customers. They service one-person operators who mostly just assemble and install kitchens. They produce for small operators who don’t have the range of equipment Mayer has; and they also cater for larger companies who have to outsource overcapacities. Mayer now also produces sports equipment, a profitable specialisation only possible due to their range of equipment.
The question of sawing or nesting is one that Mayer has also faced. They decided that to have both methods of production was the best option. They could have gone for an extra beam saw but decided not to because it is easier to automate the nesting process, something that Australian producers agree with. They also face the issue of not having the skilled people they used to and the nesting process solves that problem as well. They try and nest as much as possible but cut smaller parts on the beam saw. When choosing whether or not to cut a job on the beam saw or nest it on the Holz-Her CNC; they consider the choice of panel size and processing accuracy, as well as the type of material and the degree of utilization of the machines. On the nesting machine they cut ninety percent of their work but do all of their drilling on the Biesse Skipper vertical CNC and this is due to errors brought about by unskilled workers.
“Leitz tools are used on all of our machines”, reports Mayer. “It begins with the panel saw, where diamond sawblades and scorers are used to cut; and continues with the Diamaster Pro3 Z3+3 nesting cutter and the Diamaster Pro Z2+2 back wall groover on the Holz-Her CNC and the ‘Whispercut’ cutters on the edge-banding machine. Diamond tools were highly recommended by a Swiss colleague who really fancied the tool life, feed speed and processing quality. Today, the Pro3 Z3+3 cutter nests in diameters of 12mm and 14mm. Leitz currently is the only manufacturer who offers variants from a diameter of 10mm. This makes smaller inner radii possible, e.g. when cutting moulded parts. In addition, reduced tool diameters result in fewer chips and lower vacuum loss which means that the workpieces are held better and thus have less tendency to move on the spoil board.
The cutters are clamped with HSK 63 shrink-fit chucks and remain in the chuck for the life of the tool, even for sharpening. This is done to maintain the precision from the initial carefully-controlled setting of the tool. Three or four sets of tools are kept so that production never stops and duplicate tools are also kept in the CNC tool magazine. Mayer advises “High feed rates are a must for the router cutter in order to avoid excessive heat built-up. Our recommendations are in the range of 20 to 27m/min. With a standard material mix, this achieves a tool life of well more than 25,000 running metres.” According to Leitz, up to 40,000 running metres is not out of the question. Thanks to the spiral-shaped cutting edge arrangement, at least three cutting edges always reach over the entire working length. The PCD-tipped tools achieve higher feed speeds and longer performance times, and with irregular pitch run smoother than conventional shank cutters. Mayer have answered many of the production questions and are now ready to go to the next level; lucrative online trading. It is there that high quality and high output can be guaranteed with the right machinery and the right cutting tools.
Pictured: Leitz Diamaster Pro3