Experience with ONA

Matissart is leader in blow-moulding in France, and specializes
in high-rate work, is this correct?
Let's be a little more modest, since high-rate moulding is of interest only to some of the processing companies. In addition to these moulds of beryllium copper alloy, we make traditional moulds of stainless steel. However, the moulds for high-rate work make it possible to reduce cycle time by at least 10%, perhaps as much as 30%. The differences in price are very slight, in spite of the difficulties entailed in machining beryllium copper. Using a mould of this type, a company will find that the problems it meets with are much fewer.

What advantages do you believe are provided by the ONA machine that you recently purchased?
There were various factors that led us to opt for a Prima E900 from ONA. For one thing its dimensions, which make it possible to house pieces measuring 1500 mm by 880 mm by 400 mm (59,05 in x 34,65 in x 15,75 in). And for another, an X-axis of 900 mm (35,43 in), a Y-axis of 400 mm (15,75 in). It will take spools up to 45 kg (100 lb). It has a fine device for threading and rethreading the wire, as well as a fine wire cutter. The Aquaprima mineral filtration system is a great asset, since it eliminates the need for filter change. What it all amounts to is that we can work for long periods without interruption. And if a problem does arise, the after-sale service is superb.

This was possible owing to a combination of three factors. Corton puts it this way: "First, there are hardly any differences between the PRIMA E400 from ONA and the machines, up to 70% more costly, offered us by other firms. Second, this machine worked 24 hours, seven days a week, from the moment it was installed. And that was under the toughest conditions. The machine was being steadily used to cut pieces up to its maximum capacity of 400 mm (15,75 in). Finally, the "AquaPrima" filtering system doesn't need paper or any other consumables. This meant a great saving in time and money, since our old wire machine needed four filters a week. In order to change the filters we had to stop it for half a day per week. With the ONA machine we gain a day's production over the same period."

Know the machine

Sited in Warwick, Quantum specializes in making tempered-steel dies for presses of capacity up to 300 tons, as well as progressive tools for wiredrawing carbide in the electric industry. However, it also makes tools for injection moulds and clamping accessories. "The dies made today are much more complicated than those made in the past," says Mr Corton. "This is because car manufacturers need components of steadily greater complexity. Some of these components would never have been made without ONA's WEDM technology."

Quantum also designs and manufactures special machines for mass production. In this case ONA equipment is used for cutting components of complex profile. The engineers at Quantum are perfectly familiar with the various possibilities and features of our new machinery. They are therefore in a position to cut a broad variety of materials, such as aluminium and brass. As the Managing Director puts it, "When you have a CNC eroding machine, there is never a shortage of work."

A single electrode was used as both the rougher and finisher for each area of the cavity.

The electrode for the ribbed section was used four times. Through hole flushing was used. The ribs are 38 mm deep and 2,5 mm wide at the base.

At FECOR-STAMP they're making about twenty molds at any given moment. The equipment has to meet a demanding work pace, and it is essential to plan beforehand. However, thanks to ONA's TECHNO H-400 and PRIMA S-400 (which, as Biolatto says, are operating twenty-four hours), everything is much simpler.

GIn general machining is done on hardened steel. With some jobs, such as the shaping of thin sheet, milling isn't even considered, and penetration EDM is employed. Several electrodes are used, and full advantage is taken of the tool changer. "Precision is also very important in the case of lamps, but machining is simpler and milling can be reverted to," says the firm's spokesman.

"But for molds with a more complex geometry, which usually have four cavities and fragile components, it is unthinkable to use milling on hardened steel. EDM is safer, and in addition the results are spectacular. Usually it's a good idea to have one or two extra electrodes ".

It's not by chance that the electrodes are of copper rather than graphite. Copper electrodes mean you can keep the work area clean, and at FECOR-STAMP they're especially conscientious about everything to do with the environment. As Biolatto puts it, "Respect for nature was one of the prime considerations where choice of EDM equipment is concerned, and here ONA gets high marks thanks to its filtering systems."

PEUGEOT bought its first ONA machine in 1997: a gantry-type PD 6.120 S1 model. The article below explains their reasons for this choice. PEUGEOT recently confirmed its faith in ONA with the acquisition of two new TECHNO H-600 machines.

in 1996 the Peugeot tool department at OCMB decided to buy a new EDM unit in order to enhance its production of aluminium pressure-cast moulds. This department supplies all the tools and cast moulds required by plants in the Peugeot group. In view of its high technological level and the breadth of its experiences, it is considered one of the most important manufacturers in Europe. Its clients include firms outside the Peugeot group, such as Renault. .