THE new ULTRA4 super fast machining centre is a new generation machine that offers substantial benefits for mould and die makers who need to meet short lead times while reducing costs and improving product quality.
These demands have presented a severe challenge for mould and die makers around the world.
High speed cutting requires very high rotational spindle speeds and intense surface feeds but, within specific material dependent speed/feed vectors, chip removal temperatures decrease considerably.
The ULTRA4 high speed machining centre announced by H&H Machine Tools , is generating wide interest. It is a genuine high speed cutting machine, based on what H&H calls an ‘overhead gantry design’.
The machine operates as a stationary table with the machining axis configured as a gantry. The gantry moves overhead on columns located on each side of the table, so the workpiece remains stationary.
This design provides significant advantages for the pattern making and mould and die industries where work pieces are often large and heavy.
The overhead gantry also ensures the dynamic properties of the machine stay constant allowing extremely high machining feed rates of up to 30m/min with accelerations up to 0.5g.
For an end user, this new HSC machine offers lower cutting tool temperatures leading to extended life, high efficiency and high volume of material removal.
In terms of product, the machine offers substantially improved surface finish with less polishing required. In addition, the machine produces a high level of accuracy through reductions in thermal deviation.
To fully meet user needs in machining ‘difficult’ dies such as bumper moulds needed by the automotive industry, the ULTRA4 incorporates a fully controlled CNC-machining 4th axis.
The 4th axis spindle can swivel to incline the tool while machining is in progress. Tool inclination has significant advantages. It reduces the time required for machining via higher feedrates.
The tool length is kept as short as possible. Surface finish is improved very dramatically because the tool is maintained at a precise angle. And with ball nose end-mills, tool inclination avoids ‘rubbing’ since the tool is always maintained on the ball radius.
The machines milling spindle is driven by an 18,000rpm, 21kW motor. For more demanding machining operations, such as machining ribs in hardened tool steel, the machine incorporates a sub spindle that allows a speed of 40,000rpm using small diameter milling cutters.
The sub spindle, which has an integral spindle motor, eliminates the need for EDM.
A smart control system allows the machine to run without manual supervision. The control detects tool wear and can select a new cutting tool from the same family on a fully automatic basis.
Fully automatic measurement of tool length and control of head inclination via a laser ensures a high degree of surface finish, exceptional output and very fast machining times.