TPC 323 Flashcards
In what turning process does the reduced finished diameter always stay the same along the total length of the workpiece?
Straight turning
What is the purpose of a relief cut?
To ensure the grinding tool can advance right up to the square face of the larger diameter
What method is more accurate than the set over method?
The compound rest method, it is most often used for tapers larger than three inches/foot
How would you hold a shorter workpiece in a Lathe?
Generally hold shorter workpieces in a chuck, in a collet, or mounted on a mandrel for facing
When facing the ends of work mounted between centers what do you use?
Use a half-center mounted in the tailstock when facing the ends of work, this allows the cutting tool to be fed right up to the center hole in the work
Why do you always use the same setup used for primary boring operations in counterboring operations?
This ensures concentricity of the bored and counterbored holes
If the size and shape of a workpiece preclude mounting in a lathe, boring must be done on a?
Horizontal boring mill
When boring a short, steep taper in a workpiece what method is used?
Compound rest method for boring tapers
What is the most accurate method for boring tapered holes?
Using the taper attachment on a lathe
What controls the shape of the threads to be cut?
The profile of the cutting tool
What is the most common way to setup a drill in a lathe?
It is to mount the drill in the tailstock quill
If you are required to drill a long hole or if the workpiece is bulky and cumbersome you should mount the drill in the?
Lathe headstock
What is a more accurate method of drilling in a lathe?
Drilling with the drill held stationary
When is the “sensitive” drill pressed used?
When drilling holes where a great deal of accuracy is not required
If a job requires you to drill holes in a work piece that is too large for an upright drill press, you should use a?
Radial drill press
Spot facing is very similar to counterboring, the major difference being?
The amount of metal being removed, in spot facing only a small amount of metal is removed
To bore in a drill press you do what?
Install a boring bar in a boring head
What tool provides a way to get repeated accuracy in hole location and alignment?
Drill jigs
Can reaming be done by hand or on a drill press or lathe?
Yes
What happens during the honing process?
Fine abrasive stones contact the work surface and remove very small amounts of metal
In what process do you machine a groove in the workpieces top surface?
Side milling
What cutters are used in profile milling?
Specialized cutters are available for milling various profiles on a workpiece, cutters are made to produce concave and convex profiles
Face milling cutters that are less than 6 inches in diameter are often called?
Shell end mills
What cutters are used for slots?
Special milling cutters are available for machining keyways for all standard Woodruff keys
Shaping is less costly than milling, the ____________ cutting tool is easily made. It can often get into places where tools of other shapes cannot go.
Single-pointed
What is a slotter?
A vertical shaper
The cutting action of broaching is done by?
Pushing or pulls along
The cutting teeth on a broach increase in height from?
The end of the tool first entering the work to the end entering the work last
The very fine finishes needed for these applications can usually be obtained only by ___________ after finish machining it.
Grinding the surface, grinding can produce tolerances as close as plus or minus .000020 in. Grinding is also used to remove metal from a workpiece that is too hard for normal machining cutters and methods
When using vertical type surface grinders you can…
Grind a larger area in a given period of time. Use vertical grinding machines when you must machine pieces in a short period of time
When the workpieces dimensions must be close tolerances what is affected?
The choice of machine, the function of the workpiece, and it will help improve your skills
How can you measure angular dimensions in a circle?
The basic unit of measurement is degree. Minutes are 1/60th of a degree
Seconds are 1/60th of a minute
Why must you be careful with angular tolerances?
They can result in great variations if they become too large. This is because the spread gets larger as the distance from the center increases
At times you will be required to work with multiple dimensions which are related to each other. In this case you will find what is called?
Tolerance stack up
Another method of specifying tolerances is the unilateral system. In this system the tolerance is applied in only?
One direction from the nominal size ( either plus or minus )
Stock is usually selected that has some amount of extra material. This extra material can be?
Removed to finish the part to the required dimensions and surface finish
Why must enough material be left over after making a rough cut?
If not done the finishing cut will cause the workpiece to be undersized
What’s the first step when starting a finishing cut?
A small portion of the piece will be machined and checked for size
The type of surface finish made by a machine tool is influenced primarily by three things?
- Vibration between the workpiece and the tool
- feed marks left by the shape of the cutting tool
- the way chips are formed by the tool
What is a surface averaging instrument?
A surface averaging instrument electronically measures average roughness hieght
What is machinability?
A term that describes the ease or difficulty with which you can remove metal from a workpiece
Brittle metals like cast iron form discontinuous chips, discontinuous chips indicate?
A fairly good surface finish when working with brittle metals
The main considerations in cutting fluids use are?
Use the correct type of fluid
Use the proper amount of fluid
Correct point of fluid application
Solid lubricants are mainly used to?
Grease the sides and backs of power hacksaw and bandsaw blades
What is operational sequence?
The best possible order that machining can be done in for the most efficient use of time
Where does machining efficiency originate from?
With careful study and analysis of the total job
Should you try and keep the workpiece in the same machine for as many operations as possible?
Yes
Justifying points for obtaining specialized equipment are?
The repetitive need of a part
The need for making a part on obsolete equipment
Emergency requirements
Unavailable standard fixtures or tooling to do a given job
Should you try and use a machine that is slightly oversized for a job?
Yes
Always make sure the machine you use has enough power to?
Perform the job effectively
