DML Final Exam 2025
DML FINAL ACTUAL EXAM NEWEST VERSION
WITH COMPLETE 240 QUESTIONS AND
CORRECT DETAILED ANSWERS \\VERIFIED
ANSWERS ALREADY GRADED A+ GUARANTEED
PASS BRAND NEW 2025
Terms in this set (240)
Sometimes called "mean diameter" is the diameter in between
the major and
Pitch Diameter minor diameter. It is the theoretical diameter at which
each pitch is equally divided between threads. Pitch
diameter can be thought of as the diameter at which
the
male and female thread should meet. It could be
thought of as the working diameter.
Name two ways to measure a Thread micrometer or three-wire thread measurement method.
thread.
What is the rule of thumb The minimum recommended thread engagement for a
for the length of internal screw in an assembly is as much as the screw
thread to maximize the diameter; a better assembly will result when 1 1/2
strength of the bolt? times the
screw diameter is used.
Class 2 threads are found on most screws, nuts, and bolts used
Describe when class two fits in the
are used. manufacturing industry. Studs used on many types of
machines are examples of class 3 fits.
UNC stands for Unified National Coarse thread series
Describe UNC and UNF. and UNF stands for Unified National Fine thread series.
Each has its own strengths. Fine is generally stronger
in hard materials and coarse is generally stronger in
soft materials.
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What is the formula for The formula is D=number of the machine screw x.013in. + .060in.;
calculating the OD of a D=8 x .013in. +
.060in. = .164in.
machine screw?
How can an operator tell The feed is about right when the chip rolls into a close
by observing the chip if helix. Long, stringy chips can indicate too much
the feed is about right? feed.
Feeds are designated by a small, measured advance
In what way are power feeds
designated? movement of the drill for each revolution.
Name two different cutting The water-solubable oil types and the cutting oils, both organic
fluid types. and mineral.
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Why are countersinks made Countersink angles vary to match the angles of
with varying angles? different flat head fasteners or different taper hole
requirements.
A center drill is used to make a 60-degree countersink
What is a center drill?
hole in workpieces for lathes and grinders.
A counterbore makes a cylindrical recess concentric
When is a counterbore used? with a smaller hole so that a hex head bolt or socket
head cap screw can be flush mounted with the surface
of a workpiece.
What is the relationship The pilot diameter should always be a few thousandths
between pilot size and of an inch smaller than the hole, but not more than
hole size? .005in.
Lubrication of the pilot prevent metal-to-metal contact
Why is lubrication of the pilot
important? between it and the hole. It will also prevent the
scoring of the hole surface.
As a rule, how do the A general rule is to use approximately one third of the
cutting speeds of an cutting speed when counterboring, as when using a
equal-sized counterbore twist drill with the same diameter.
and twist drill compare?
Feeds and speeds when counterboring are controlled
What affects the selection
to a large extent by the condition of the equipment,
of feed and speed when
the available power, and the material being
counterboring?
counterbored.
Is performed with a counterbore. It makes a flat
What is spot-facing?
bearing surface, square with a hole to set a nut,
washer, or bolt head.
What important points Counterboring requires a rigid setup with the
should be workpiece securely fastened and provisions made to
considered when making a
allow the pilot to protrude below the bottom surface
counterboring setup?
of the workpiece.
Machine reamers are identified by the design of the
How is a machine reamer
identified? shank-- either a straight or tapered shank and
usually a 45-degree chamfer on the cutting end.
A chucking reamer is a finishing reamer, the fluted
What is the difference part is cylindrical, and the lands are relieved. A rose
between a chucking and reamer is a roughing reamer. It can remove a
a rose reamer? considerable
amount of material. The body has a slight back taper
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