Not every sheet metal fabrication shop wants a CNC press brake with all the extras, such as 3D graphics, said a subcontractor, which has invested in a straightforward CNC model.

Many general sheet metal fabrication shops do not need a press brake with 3D colour graphics in the control, CNC side-to-side motion of the back stop fingers (Z-axis) or laser compensation after each bend This is the view of John Lehan, managing director of Nicholls Fabrications in Garforth, Leeds, UK, which has invested in a Turkish-built Baykal APHS 3106x120 CNC press brake (brake press - USA) through sole agent, Press and Shear Machinery

"The machine cost around two-thirds the price of five other 3m, 120 tonf capacity models we looked at, all of which had unnecessarily high specifications for what we need," he said.

"Nevertheless, the Baykal does have computer numerical control of four axes as well as automatic crowning, with more CNC axes available as options.

The press brake is also compact and quiet in operation." Established in 1970, Nicholls Fabrications started out doing a lot of work for Leeds City Council, but only fencing contracts remain.

A majority of components and assemblies are currently supplied to the building and construction industry.

The present Government's programme of building new schools has increased the subcontractor's workload in recent years, typical contracts being for the supply of aluminium components for doors and windows.

Much of the company's output is supplied ready-painted from a powder coating facility adjacent to the machine shop.

Around 90% of components are made in aluminium ranging from 0.9 to 6mm thick, although mild steel and stainless steel are also regularly processed.

The Baykal sits alongside two other CNC press brakes of 4m capacity, one of which is a 200 tonf (2000kN) Elga Synchro supplied by Press and Shear Machinery about 20 years ago.

Lehan said that they have installed 15 sheet metal processing machines from this supplier over the years.

Despite having a lower tonnage than the other press brakes on site, the Baykal is nevertheless capable of bending 2m lengths of 6mm gauge mild steel and will tackle 3mm stainless over the full three metres.

Batch size can vary from one-off to several thousand, 30- to 40-off being typical.

General accuracy on drawings supplied by customers is +/-1 to 2mm, although the machine is capable of holding considerably tighter tolerances if necessary.

Dave Edgley, works manager at Nicholls Fabrications, explained how easy the Baykal is to program at the Delem DA-66W control.

After entering the type of material and its thickness, the component profile is created on screen by giving numerical values to a sequence of dimensions and angles, starting from one side.

The relevant press brake tooling is selected from a library of alternatives and the 'compute' button is pressed.

The control automatically generates the bending program and advises the width of sheet that needs to be cut to produce the component, taking into account the bend allowances.

Cycle time is displayed on-screen, assisting with quotes, job allocation and managing workflow through the shop.

Commented Edgley, "We can also use the machine in manual mode, which is quicker if we only need a few components with one or two bends.

But for longer runs of more complex parts with five or six bends, say, programming the job results in much higher productivity as each component comes off the machine two to three times faster.

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