Big Daishowa Speed Finisher roughs and finishes in one operation
1 min read
The Speed Finisher face milling cutter introduced by Big Daishowa for high-speed finishing of cast iron, aluminium and other non-ferrous metals, has inserts that are adjustable to within 1 micron. This, the Japanese manufacturer says, results in a mirror-like machined finish using spindle speeds up to 20,000 rpm.
Big Daishowa reports that In trials, an ADC12 aluminium die cast crankcase was machined using the Speed Finisher with coolant at 4,000 m/min cutting speed, 9,550 mm/min feedrate and 2.5 mm depth of cut to a mean roughness depth of Rz 0.55 micron. Roughing and finishing were combined into a single operation. When dry cutting an FC250 grey cast iron machine tool bed at 1,500 m/min surface speed, 3,600 mm/min feedrate and 2.0 mm depth of cut, an Rz of 0.67 micron was achieved together with 1 to 2 microns surface flatness.
The insert grade choice is either high density sintered DA2200 PCD (polycrystalline diamond) for aluminium and non-ferrous metals, or CBN (cubic boron nitride) for cast iron. After clamping the insert, a fine-pitch screw raises or lowers it directly and precisely by turning a nut at the side. The company says a bespoke presetter, which further improves accuracy, reduces adjustment time to under 15 sec.
The low profile cutter body enhances the cutter's rigidity while reducing vibration and distortion and hence minimising the height differences in the machined surface. Low mass translates into a low weight, assisting good performance even on small machine tools with 30-taper spindles.
Speed Finisher comes in 50, 63 and 80 mm diameters. Coolant is delivered directly to the cutting edge when used in combination with the Face Mill Arbor Type FMH, which when cutting aluminium is effective in avoiding built-up edges and possible re-cutting of swarf.
