Living in the plastic age

Additionally, the launch of a new range of circular saws from Kasto, designed specifically for the cutting of plastics and aluminium, makes the cutting of delicate materials a simple task. Solutions reports.

Installed in September 2009 at Ensinger's headquarters and main distribution centre in Tonyrefail, South Wales, the 540mm capacity saw is resulting in at least a 10% increase in yield from each length of stock that is cut, according to Steve Tipples, director and general manager.

In exceptional cases, up to 40% of some materials is saved from being scrapped and with 60-70% of the company's plastic stock at Tonyrefail sawn into millions of pieces every year, savings are considerable, especially with some materials costing up to £100 per kilogram.

Bar, tube, profile and plate from mid size up to 500mm across were previously cut using an ageing bandsaw on which the blade tended to wander, producing a wavy cut surface. Typically, it meant that if ten pieces could theoretically be cut from a length of stock, in practice only nine might be produced at times due to material loss between the cuts.

A further drawback was that sometimes the billet ends had to be planed flat by hand to within the customer's specification, incurring extra labour and energy costs as well as increasing leadtime from order to delivery.
According to Ensinger, all of these problems have been solved following the arrival of the Missler DEB 540 ce bandsaw enabling fast, accurate and reliable cutting. Moreover, much closer tolerances can now be held which can save the user time and money by not having to machine the cut faces.

Heavy artillery

When John Sullivan and Carl Morgan, respectively the company's logistics manager and purchasing manager, researched the market for a suitable bandsaw, they knew that a machine normally sold into the metalcutting sector was required. A woodworking variant would simply be too lightweight.

They evaluated machines from a large number of suppliers but the build quality of the Missler – part of the Kasto group – stood out as being most suitable for Ensinger's needs. Once the order had been placed with Kasto, however, a competitor focused on the perception in the marketplace that Missler spares would be a problem in years to come, as machine production ceased in 2007 after Kasto bought the company.

Ernst Wagner, managing director of the group's UK subsidiary, dispelled the rumour by stating that availability of Missler spares was guaranteed for a minimum of 10 years, as required by European law. In the UK, there are over 150 Missler machines being maintained by Kasto.

Tough going

The Missler has indeed proved to be a rapid in operation. Over a 16 hour daily shift, it cuts through Ensinger's wide range of plastic materials, including some very tough varieties. For example, 450mm diameter Tecast TM cast polyamide tube of 50mm wall thickness is sawn in fractionally over 1.5 minutes, using a band speed of 110m/minute and a feed rate of 300mm/minute which equates to cutting 420cm²/minute.
When sawing 500mm diameter solid bar of the same material, a feed rate of 100mm/minute completes the cut in five minutes at 390cm²/minute.

Established in 1987, Ensinger's UK subsidiary in Tonyrefail now coordinates the activities of seven other branches around the UK, which provide a personalised plastics distribution service to local industries. Customers include end users, machine shops and other distributors serving a wide range of sectors including food and drink, aerospace, defence, medical, Formula 1, offshore and nuclear.

Some centres have cutting and machining facilities, supplying batches of parts ranging from one-off to several thousand at a time and no metal is stored or processed on any of the sites to avoid contaminating the plastic materials. The headquarters in Wales is also heavily involved in application-based design and development for its customers.

Ensinger has grown steadily over the past 22 years and employs 240 staff, of which 70 are dedicated to machining.
As the one of the market leaders in the industry, Ensinger regards education and training as part of its responsibility and is active on many fronts. It has an internal training school at Tonyrefail with apprentices studying for NVQs, and has established a machine shop at the local Tonyrefail Comprehensive to teach practical aspects of turning, milling and sawing of all types of material. The company also has close links with Swansea University and sponsors a room dedicated to testing of materials.

Damage limitation On the subject of cutting plastics, aluminium and other delicate materials, also new from the Kasto camp is a new range of circular saws. Models in the KastoAlu range comprise manual and semi-automatic downstroking models M 10 and U 10, semi automatic upstroking models U 12, 14 and 20, and a fully automatic upstroking saw, A 13. Except for the latter, all saws are capable of double ended mitring as well as straight cutting. Complementing the KastoDisc machine series for relatively light duty cutting of steels and most common metals, KastoAlu machines fall within the German manufacturer's workshop range of saws. Rectangular stock up to 300mm by 100mm can be processed on the U 20 while the U 12 accommodates 110mm by 70mm material. Capacity of the automatic A 13 is 200mm by 90mm. Complex mitre cuts are possible on the M 10 and U 10 models as the 400mm diameter saw blade can be positioned up to 45° left or right and at the same time inclined at up to 45° to the vertical. This allows compound mitre cuts, which are increasingly required in complicated building structures. Hydro pneumatic, infinitely variable saw feed is a feature of all automated models in the KastoAlu series. Minimum lubrication of the carbide tipped saw blade is common throughout the range and so too is the provision of a compressed air gun and a port for connecting chip extraction equipment. Mitre angle is up to ±90° on the larger semi automatic machines. The KastoAlu A 13 is a numerically controlled, automatic circular saw with an additional function for semi automatic operation, designed for 90° cutting not only of aluminium and plastic profiles but also of solid materials. Features include a precision ballscrew for material feed and infinitely variable cutting height adjustment. Kasto
www.kasto.uk.com