DOLittle - lathe

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A new convincing concept!

  • Highest precision for smallest turning parts
  • Space-saving and compact design
  • Optionally with opposed spindle
  • Optionally with Y-axis
  • Lowest setting-up times by external setting
  • Driven tools with speed up to 18.000 rpm
  • Spindle speed up to 15.000 rpm

Due to its design, this lathe is ideally suited for maximum precision with small to very small component dimensions. The flexible modular system offers a wide variety of machine variants in very compact installation space, all of which are characterized by an extremely low thermal cycle.

In addition to its precision, the innovative tool concept is designed for easy handling, external tool measurement, and the shortest possible set-up times. The turning machines are accommodated in tool blocks with five positions each. Via a specially developed interface, these blocks can be installed and removed within a few seconds, guaranteeing a changeover accuracy of < 0.01 mm. Outside the lathe, the new tools are inserted, measured and the coolant supply lines are adapted to the respective tool positions. Ideally, this is done while the CNC lathe is still processing the current job. A wide range of turning spindles with radial and axial run-out are available.

Down to < 0.5µm and speeds of up to 15,000 rpm are available in conjunction with a wide variety of clamping systems for sensitive clamping of the workpieces. Y-axes expand the machine's range of applications in machining and also reduce setup times due to the fact that tools can be calibrated via the NC axes of the lath itself. Up to six milling spindles in conjunction with an NC swivel axis enable a wide range of options for machining complex workpieces.

All variants of the DOLittle series can be automated either by Benzinger's own loading and unloading devices with the shortest possible workpiece change times or by separate robot cells. The addition of a bar feeder also enables complete machining from the bar.State-of-the-art controls from Siemens and Fanuc with various programming options complete the overall package.

Version B1 - DOLittle lathe

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The linear tooling system offers the highest stability and shortest chip-to-chip times. In combination with the Y-axis, the tools are arranged in three rows one above the other. For driven tools, the six-fold milling device with NC swivel axis (0° to 90°) is available. Alternatively, high-frequency spindles, grinding spindles, air turbines, etc. can be installed in the tool blocks.

Version B2 - DOLittle lathe

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A tool turret with 12 VDI-20 tool stations and optionally 6 driven tool stations can be supplemented by additional linear tool blocks to combine the precision and variety of the linear structure with the flexibility of a tool turret. The advantages of the Y-axis are fully utilized.

Version B3 - DOLittle lathe

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The DOLittle B3 lathe is equipped with a main spindle and a counter spindle to enable the complete machining of workpieces. Due to its design, the counter spindle inside the turning machine can be moved in three directions (X / Y / Z) to transfer the workpiece to the main spindle. Precise form and position tolerances from the first to the second workpiece side can thus be reliably maintained. The innovative tool blocks in combination with the Y-axis and the six-axis milling device with NC swivel axis enable the machining of complex and high-precision components.

Version B5 - DOLittle lathe

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The performance of the turning machine can be doubled by using two parallel main spindles, each with its own separately controlled and programmed tool carrier. The combination of the Y-axis with the tool blocks of the lathe series DOLittle is arranged in three rows one above the other allowing the use of sister tools to significantly extend the autonomy time. An integrated loading system matched to each component guarantees the shortest cycle times at maximum output.

This makes the DOLittle B5 CNC-lathe a highly productive solution for machining repeat parts.

Version B6 - DOLittle lathe

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The DOLittle B6 variant combines the advantages of the DOLittle design with the productivity of simultaneous machining.

The separate arrangement of the slide units at the smallest possible distance makes it possible to keep the machine's heat cycle to a minimum.

With the two equivalent spindles, speeds of up to 15,000 rpm can be achieved on both the main and counter spindles. Optionally, the counter spindle can be equipped with an internal clamping cylinder, which promises maximum roundness on the component, as the rotating masses are significantly reduced. The DOLittle B6 has a fully functional Y-axis (optional) under the counter spindle, which means that the transfer position from the main spindle to the counter spindle can be adjusted in all three linear spatial directions via the control.

The machine concept is optimally suited for simultaneous machining of small to medium component sizes. It is possible to produce parts with a diameter of up to 26 mm with the highest precision. Thanks to the two VDI-25 turrets on optional Y-axes, even complex components up to 60 mm in length can be produced in the best quality without any problems. In addition, the DOLittle B6 can be equipped with a tailstock, which is mounted next to the counter spindle and enables the machining of longer and slim components. With the DOLittle-B6, high-precision simultaneous machining is possible in the smallest space.

Innovative tool concept

In addition to its precision, the innovative tool concept is designed for the simplest possible handling, external tool measurement, and the shortest possible set-up times. The CNC-turning machines are accommodated in tool blocks with five positions each. Via a specially developed interface, these blocks can be installed and removed within a few seconds, guaranteeing a changeover accuracy of < 0.01 mm within the turning machine. Outside the lathe, the new tools are inserted, measured and the coolant supply lines are adapted to the respective tool positions. Ideally, this is done while the lathe is still processing the current job.
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Tool block DOLittle lathe for static tools:


  • Changeover time <10 seconds 

  • Setup and measurement of the tools outside the turning machine, thus parallel to the machining process

  • Changing accuracy < 0.01 mm

  • 4 receptacles each ø25 mm and 1 x 10mm (square)

  • In diameter 25, hydraulic expansion sleeves for tool shank ø12 mm, holders for ER16 and ER11 collets as well as high-frequency spindles can be clamped

  • Internal coolant supply for all tools, high coolant pressure possible for individual tools 

DOLittle - lathe - hard machining

Innovative tool concept

Valve seats in series hard turning significantly more economical than conventional turning and grinding

Replacing grinding with hard turning has been proven in numerous applications. It demonstrates itself to be particularly advantageous. It reduces investment and operating costs, as costly grinding machines are no longer required. The cycle times are shorter. Components are finished on only one machine in one process. Hard-turned components are often more accurate than ground ones because there are no shape errors due to incorrectly profiled grinding wheels. With hard turning, the shape accuracy depends solely on the NC axes of the lathe. In addition, hard turning is more flexible. It is possible to machine any contours that cannot be achieved by form grinding due to grinding wheel profiles that cannot be aligned. Furthermore, hard turning is mostly dry machining. This eliminates the need for time-consuming cleaning and drying of the finished workpieces. In hard turning, the surface quality can also be optimised with the help of the technology parameters cutting speed and feed rate. In this way, hard turning also achieves mirror-smooth, less than 2 to 3µm accurate surfaces on curved and profiled workpiece contours.

That is why subcontractors are increasingly machining small valve seats and pistons for axial pumps by hard turning, for example. The combination of hard turning and subsequent grinding is also becoming increasingly important, especially when surfaces must have a typical grinding pattern due to the way they function. All Benzinger turning centres are suitable for hard turning. They convince by highest stability and accuracy. For hard machining on very small parts, the machines of the DOLittle series are usually used. These lathes already have a Y-axis as standard equipment. The tools are arranged on linear slides. A clamping system developed by Benzinger ensures highly stable tool clamping and fast, highly accurate tool changing. The tools are pre-set and adjusted outside the lathe during machining. The tool blocks, each with five tools, can be inserted within a very short time with a changeover accuracy of less than 0.01 mm. For machining at sufficiently high cutting speeds, spindles with a roundness of less than 0.5 µm are available, which can reach speeds of up to 15000 rpm.

As an option, all lathes can be equipped with automation solutions. The automation systems designed and realised by Benzinger are advantageous for large series production. But vibratory conveyors, robots and bar loaders can also be attached to the machines. This ensures that subcontractors can hard-turn small workpieces, such as valve seats with a diameter of only a few millimetres, in a highly automated and thus extremely economical way in large series.

DOLittle - B5