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Milling Machines

Session 13

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Vertical Milling Machine

• Developed in 1860's• Combines vertical spindle of drill press

with longitudinal and traverse movements of milling machine

• Milling process may be vertical, horizontal, angular, or helical

• Can be used for milling, drilling, boring, and reaming

• Can machine in one, two, or three planes• X, Y, Z

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Vertical Milling Machines• Equipped with variable speed spindles

• Permits wide range of speeds

• Spindle head housing swiveled as much as 90 degrees right and left, and limited backward and forward for angular operations

• Longitudinal and crossfeed movements of table operated by hand or automatic feeds

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Variety of Operations

• Face milling

• End milling

• Keyway cutting

• Dovetail cutting

• T-slot and circular slot cutting

• Many facing operations done with fly tool

• Gear cutting

• Drilling

• Boring

• Jig boring

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Types of Vertical Milling Machines

• Ram-type• Most common • Features of horizontal milling machine• Cutter spindle mounted in vertical position• Spindle head may be swiveled allowing

machining of angular surfaces

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Types of Vertical Milling Machines

• Ram-type

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Parts of Ram-Type Mill

• Base • Made of cast iron

• May contain coolant reservoir

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Parts of Ram-Type Mill

• Column• Machined face

provides ways for vertical knee movement

• Upper part machined to produce turret for overarm mount

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Parts of Ram-Type Mill

• Overarm • Round base• May be adjusted

toward or away from column and rotated

• Locked into position

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Parts of Ram-Type Mill

• Head • Attached to end

of ram• Universal-type

machines allow swivel in 2 planes

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Parts of Ram-Type Mill

• Motor • Mounted on top

of head• Provides drive to

spindle through V-belt

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Parts of Ram-Type Mill

• Spindle speed• Speed changed

by variable-speed pulley/crank or by belt changes and reduction gear

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Parts of Ram-Type Mill

• Knee • Moves up and

down on face of column

• Supports saddle and table

• Does not contain gears for automatic feed

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Heavy-Duty Vertical Milling Machine

• Used for machining operations that require larger cutters and good rigidity

• Adapted to operations with both end mills and face mills• Profiling interior and exterior surfaces• Milling dies and molds• Locating and boring holes in vises and

fixtures

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Heavy-Duty Vertical Milling Machine

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Horizontal Boring Mill

• The Horizontal Boring Mill (HBM) is classically a large machine. Although small items can be machined on them, they are usually reserved for the large to very large workpieces.

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Typical Boring Mill Operation

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Typical Boring Mill Operation