Citizen Miyano GN-4200

The Citizen Miyano GN-4200 is a larger GN chucking lathe: one spindle at up to 8,000 rpm with a 5.5/3.7 kW motor (15-min/continuous), collet capacity of 45 mm dia. and a maximum machining length of 80 mm. Tools are carried on a horizontal linear turret running on dovetail slides.

The step up is in every working figure. Against the Miyano GN-3200, collet capacity goes from 35 mm dia. to 45 mm dia., machining length from 50 mm to 80 mm, and the spindle motor from 2.2/1.5 kW to 5.5/3.7 kW, while the weight stays at 1,500 kg. The slide strokes grow too, to 300 mm in X and 250 mm in Z. The longer X stroke gives room for more tools side by side on the linear turret, which matters because each tool change is a slide move.

Dovetail slides on both X and Z are a deliberate choice for this kind of machine. They have a large contact area and good damping, which helps surface finish in light precision turning, at the cost of the rapid speeds a linear-guide machine would offer. The table gives no rapid traverse figure, so ask for one if cycle time on short parts is the deciding factor.

The machine is 1,695 mm high and needs a floor space of W1,350 mm×D1,325 mm, close to square. The table does not list live tools, chuck types or a second spindle, so treat it as a single-sided turning machine for second operations or for parts that are finished in one chucking.