Machining and Machining Operations: Part B

What are mills generally used for?

• Machining flat surfaces

• Machining parallel surfaces

• Cutting keyways/keyseats

• Drilling holes

• Boring

What are the 4 types of milling machines?

• Plain horizontal

• Universal horizontal

• Standard vertical

• Ram vertical

What is a plain horizontal milling machine?

A milling machine with a horizontal spindle and a table that does not swivel, only moves in right angles

What is a universal horizontal milling machine?

A milling machine with a horizontal spindle and a table that can swivel up to 45 degrees in either direction

What is a standard vertical milling machine?

A milling machine with a vertical spindle and a table that does not swivel, only moves in right angles. They are less rigid than horizontal mills but more adjustable and versatile.

What is a ram vertical milling machine?

A milling machine with a vertical milling head mounted on a mobile ram that can be positioned forwards or backwards on top of the column. They are the least rigid mill but are the most adjustable and versatile.

How are milling machines sized?

By their range of motion and size of motor.

What are the components of a milling machine?

• Base

• Column

• Overarm (only on horizontal mills)

• Ram (only on ram mills)

• Head (only on vertical and ram mills)

• Knee

• Saddle

• Table

What are the three table movements?

• longitudinal traverse (x)

• cross traverse (y)

• vertical traverse (z)

What is rapid traverse?

Fast movement used for positioning

What are the three parts of mill spindles?

• spindle nose (drive keys to drive the cutting tools)

• steep machine taper (3 1/2” steep taper)

• spindle draw bolt (holds tool shank in spindle bore)

How do you adjust a mills spindle speed??

By using the speed selector levers to change the gears or belt ratios or by adjusting the variable speed wheel/knob on mills with variable speed drives.

What are the parts of a portable keyseat mill?

• Self aligning v-base

• Bar or chain clamp

• Upper frame with crank

• Dovetail slide

• Motor and spindle with collet chuck

What are arbor milling cutters?

Cutters mounted to an arbor/mandrel with a key that are used by horizontal mills. Their advantages are fast, accurate, and ridgid. Designated by outside diameter.

What are the 4 kinds of solid endmills?

• Straight

• Weldon (notched)

• Threaded

• Double ended

What is the rule for endmill depth of cut?

Depth of but is ½ the endmill diameter

What are the two kinds of endmill cutting points?

• Center/end cutting (can plunge)

• Non-center cutting

Where do endmills cut?

On their points and edges.

What are the endmill flute types?

They come in two, three, and 4 flute types. The more flutes, the faster the cutting.

What is a woodruff key cutter?

Single purpose cutting tools machined to cut exact woodruff key sizes.

What are fly cutters?

A single-point rotary cutting tool used in milling machines to face and flatten the surface of a workpiece.

What are face mills?

wide, rotating cutting tools with multiple insert teeth used in milling machines to quickly flatten and smooth the top surface of a workpiece.

What are the nine common types of holding devices in machining?

• Vises (plain, swivel, universal)

• Step blocks

• Clamps

• T-bolts and T-nuts

• Parallels

• Jackscrews

• Shims

• Angle plates/ Angle Blocks

• V-blocks