Chapter 15: Other Lathe Operations
Drills over ____ in diameter require a pilot hole.
1/2″
What cutting speed is recommended when reaming on the lathe?
2/3 that of a similar drill size
Boring mills are used to bore small, delicate workpieces.
False
Holes that are to be reamed are drilled slightly oversize to allow sufficient stock for reaming.
False
Knurled patterns are created by cutting grooves into the workpiece.
False
An automatic screw machine performs a large number of operations either simultaneously or in a very rapid sequence.
True
Knurling should be performed before a shaft is turned to a smaller diameter.
True
The type and size of boring bar to be used is determined by the size of the hole to be bored.
True
How is a steady rest used?
When additional support is needed to prevent long and/or slender work from springing away from the cutting tool during machining. It also reduces chattering
What is a mandrel?
a slightly tapered, hardened steel shaft
What is sometimes used when several identical pieces must be produced?
a tracing or duplicating unit
Reaming is an operation used to produce a hole that is ____.
accurate in diameter and finish
When boring on a lathe, ____.
additional front clearance must be ground on the cutting tool to avoid rubbing
A grinding wheel must be ______________________________ and run true to obtain a smooth, accurately sized job.
balanced
The follower rest bolts to the ______________________________.
carriage
Accuracy in drilling requires a(n) ______________________________ starting point for the drill.
centered
Work mounted on a mandrel is usually machined between ______________________________.
centers
When boring on a lathe, additional front ______________________________ must be ground on the cutting tool to prevent it from rubbing.
clearance
How should a lathe be protected when using a tool post grinder?
cover the lathe bed, cross slide, and other parts with canvas or heavy kraft paper
When reaming on the lathe, use a ____.
cutting speed about 2/3 that of a similar size drill
A pilot hole should have a diameter equal to the larger drill's ______________________________.
dead center
Angular knurls raise a(n) ______________________________ pattern.
diamond
Grinding wheels are dressed with a(n) ______________________________ wheel dresser.
diamond
A(n) ______________________________ mandrel permits work with openings that are not a standard size to be turned.
expansion
The ______________________________ provides support directly in back of the cutting tool and moves along during the cut.
follower rest
Describe the knurling process.
forming a certain shape into the circumference of the stock for the purpose of a grip, looks, or increasing stock diameter
A(n) ______________________________ mandrel is helpful when several pieces must be turned.
gang
A ______________________________ (high/low) spindle speed is used for polishing.
high
Lathe filing requires a ______________________________ (high/low) spindle speed.
high
Boring is an internal machining operation ____.
in which a single-point tool is used to enlarge a hole
The ______________________________ method of filing is the safest way to file on a lathe.
left hand
A(n) ______________________________ lathe file has superior cutting action compared to a regular mill file.
long angle
What can be done to prevent work from freezing to a mandrel?
lubricate with light oil
Why should the largest possible boring bar be used for boring operations?
maximum rigidity
A boring bar is positioned ____ for machining.
on or slightly below center
The steady rest and follower rest are used to perform all of the following tasks except ____.
reduce side pressures on the work
When boring with long, slender boring bars, chatter may occur but can usually be eliminated by ____.
reducing tool overhang
The automatic screw machine has been developed for the high-speed production of large numbers of ______________________________ (small/large) parts.
small
A(n) ______________________________ mandrel is made from hardened steel that has been machined with a slight taper.
solid
The hole size to be bored determines all of the following except ____.
spindle speed
Holding a file ______________________________ against the rotating work will cause it to load with metal and score the surface of the work.
stationary
When drilling on a lathe, drills larger than 1/2″ (12.5 mm) in diameter usually have ______________________________ shanks.
taper
Why is boring done?
to expand holes accurately that are concentric with the stock diameter
Filing on a lathe should be kept to a minimum. When is filing recommended?
to remove burs, round off edges, and blend in form cut lines
What will cause the workpiece to bend permanently when being knurled?
too much pressure
A boring bar should extend from the ______________________________ only far enough to do the job.
tool holder
Limited production runs are sometimes produced on a manually-operated ______________________________ lathe.
turret
Work that is too large or too heavy to be turned in a horizontal position is machined on a(n) ______________________________.
vertical lathe
The steady rest is bolted directly to the ______________________________.
ways
What will occur if too much pressure is applied when knurling?
work surface becomes hardened during the op and the knurled section could "flake off". also tends to bend the shaft