DML 383-510
The root truncation for unified threads and for American National threads is found by .125P. What should the flat on the end of the threading tools be for both systems on a 1/2-20 thread?
.006
Calculate the offset for the taper shown in Figure1-380. The Formula is
.625 inches
How far should the compound set at 30 degrees move to cut a 1/2-20 Unified thread.
.708/20 = .0354 Unified. .75/20 =.0375 AMERICAN NATIONAL
Calculate the rpm for roughing a 1.5 inches diameter shaft or machine steel.
240
What is the drill point diameter of a number 5 center drill?
3/16 inch
If the cuttting speed of aluminum is 300 sfm and the workpiece diameter is 4 inches, what is the rpm?
300
On what percent of thread are tap drill charts usually based?
75 percent.
How is the tool aligned with the work?
A center gage is used to align the tool to the work.
How can a steady rest be set up when there is no center hole in the shaft?
A center punch mark is placed in the center of the end of the shaft. The lower two jaws on the steady rest are adjusted until the center punch mark aligns with the point of the dead center.
Workpieces mounted between centers are driven with lathe dogs. Which type of plate is used on the spindle nose to turn the lathe dog?
A drive plate.
Reamers will follow an eccentric drilled hole, thus producing a bellmouth bore with runout. What device can be used to help eliminated bellmouth? Does it help remove the runout?
A floating reamer holder will help eliminate the bellmouth, but it does not remove the runout.
When a long slender shaft needs to be turned or threaded for its entire length, which lathe attachment could be used?
A follower rest.
You have a rectangular workpiece that needs a facing operation plus center drilling, and a universal chuck is mounted on the lathe spindle. What is your procedure to prepare for maching?
A lathe board is placed on the ways under the chuck, and the chuck is removed, because it is the wrong chuck to hold rectangular work. The mating parts of an independent chuck and the lathe spindle are cleaned and the chuck is mounted. The part is roughly centered in the jaws and adjusted to center by using the back of a tool holder or a dial indicator.
What tool is used for facing shaft ends when they are mounted between centers? In what way is this tool different from a turning tool?
A right hand facing tool is used for shaft ends. It is different from a turning tool in that its point is only a 58 degree included angle to fit in the narrow space between the shaft face and the center.
After a scratch cut is made, what would be the most convenient method to measure the pitch of the internal thread?
A screw pitch gage should be used.
By what methods are threads cut or chased with a single point tool in a lathe? How can a given helix or lead be produced?
A series of cuts are made in the same groove with a single point tool by keeping the same ration and relative position of the tool on each pass. The quick change gearbox allows choices of various pitches or leads.
Give two advantages and two disadvantages of turning between centers.
A shaft between centers can be turned end for end without loss or concentrically, and it can be removed from the lathe and returned without loss of synchronization between thread and tool. Cutting off between centers is not done, as it would break the parting tool and ruin the work. Steady rest work is not done with work mounted in a center in the headstock spindle.
Standard plug or bottoming taps can be used when hand tapping in the lathe. If power is used what kind of tap works best?
A spiral point tap works best for power tapping.
How can you avoid drilling oversize with a tap drill?
A tap drill can be used as a reamer by first drilling with a drill that is 1/32 to 1/16 undersized. THis procedure ensures a more accurate hols size by drilling.
When should a zero or negative rake be used?
A zero rake should be used for threading tools. A zero to slightly negative back rake should be used for plastics and brass; because they tend to "dig in"
Describe the procedure in turning to size predictably?
After roughing is completed, .015 to .030 is left for finishing. The diameter of the workpiece is checked with a micrometer, and the remaining amount is dialed on the crossfeed micrometer collar. A short trial cut is taken and the lathe is stopped. This diameter is again checked. If the diameter is within tolerance, the finish cut is taken.
Name two similarities and two differences between American National and Unified threads.
American National Standard and Unified Standard threads both have the 60 degree included angle and are both based on the inch measure with similar pitch series. The depth of thread and the classes of thread fits are different.
Nicks and scratches are damaging to lathe ways. What means can be employed to prevent them?
Because most nicks come from dropping chucks and heavy workpieces on a lath, a lathe board used every time a chuck is changed or heavy work is installed will prevent much of this damage. A tool board will help keep tools such as files from being laid on lathe ways.
Why should the dead center be frequently adjusted when turning between centers.
Because of expansion of the workpiece from the heat of machining, it tightens on the center, thus causing more friction and more heat. This could ruin the center.
Why will you not achieve the same surface finish (tool marks per inch) on the face of a workpiece as you will on the outside diameter when on the same power feed?
Because the crossfeed is geared differently (about one third of the longitudinal feed), the outside diameter would have a coarser finish than the face.
In what ways can a steady rest be useful?
Because they are useful for supporting long workpieces, heavier cuts can be taken, or operations such as turning, threading, and grooving may be performed without chattering. Internal operations such as boring may be done on long workpieces.
What does deflection of spring of the boring bar cause when cutting internal threads?
Boring bar and tool deflection cause the threads to be undersize from the calculations and settings on the micrometer collars.
Are boring bar holders that are used in standard tool posts more or less rigid than those held in quick change toolholders?
Boring bars are less rigidly held in the older style standard tool posts.
What are two advantages in turning a single point threading tool 180 degrees opposite the operator?
By using a 1/16 inch undersized drill and boring to the minor diameter.
How can a steady rest be used on an irregular surface such as square or hex stock?
By using a cat head.
In what way is percent of thread obtained?
By varying the bore size, usually larger than the minor diameter. This is done to make tapping easier.
Give two reasons for center drilling a workpiece in a lathe.
Center drilling is done to prepare work for turning between centers and for spotting workpieces for drilling in the lathe.
Name two causes of center drill breakage.
Center drills are broken as a result of feeding the drill to fast and having the lathe speed too slow. Breakage also can result from having the tailstock off center, the work off center in a steady rest, or a lack of cutting oil.
Describe the kinds of tapers that may be made by using a form tool or the side of a tool.
Chamfers, V-grooves, and short tapers may be made by the form tool method.
In what ways can chips be broken?
Chips can be broken up by using coarse feeds and maximum depth of cuts for roughing cuts and by using tools with chip breakers on them.
What should you do when you are finished using the lathe?
Chips should be cleaned from the lathe and swept up on the surrounding floor area. The lathe ways and slides should be wiped and oiled.
Why are drilled holes not used for bores in machine parts such as pulleys, gears, and bearing fits?
Drilled holes are not sufficiently accurate for bores in machine parts, as they would be loose on the shaft and would not run true.
What kind of tools are used in the lathe tailstock?
Drilling machine tools are used in the lathe tailstock.
Explain which positions on the threading dial are used for engaging the half-nuts for even, odde, and fractional numbered threads.
Even numbered threads may be engaged on the half-nuts at any line. Odd numbered theads at any numbered line. It would be best to use the same line everytime for fractional numbered threads.
Why should you avoid excess overhang with the tool and toolholder when roughing?
Excess overhang promotes lack of rigidity. THis causes chatter and tool breakage.
Describe a face driver.
Face drivers use multiple driving pins that dig into the work and are hydraulically compensated for irregularities.
Why should fine chips, filings, and grindings be cleaned from the ways and slides frequently?
Fine chips, filings, and grindings form an abrasive sludge that wears and scores the sliding surfaces. Frequent cleaning will help prevent damage to the machine.
What is the difference between a standard toolholder for high speed steel tools and for carbide tools?
For high speed tools the square tool bit hole is angled upward in relation to the vase of the toolholder, whereas it is parallel to the base for carbide tools.
How much should be left for finishing?
For most purposes where liberal tolerances are allowed, 0.015 to 0.030 inches can be left for finishing. When closer tolerances are required, two finished cuts are taken. with 0.005 to 0.010 in left for the last finish cut.
Name four methods of measuring tapers.
Four methods of measuring tapers are using the plug and ring gages using a micrometer on layout lines, using a micrometer with precision parallels and drill rod on a surface plate, and using a sine bar, gage block, and a dial indicator.
By what means are grooves and thread relief made in a bore?
Grooves and thread relief are made in bores by means of specially shaped or ground tools in a boring bar.
Other than hardness and toughness, what is the most important aspect of a lathe tool.
Its geometric form: the side and back rake, front and side relief angles, and chip breakers.
State three reasons for kurling.
Knurling is used to improve the appearance of a part, to provide a good gripping surface, and to increase the diameter of a part for press fits.
Which would be best for making a 6 inch diameter internal thread using an engine lathe: a tap or a single point threading tool. Explain.
Large internal threads are produced with a boring tool. Heavy forces are needed to turn large hand taps, so it is not advisable to use large taps in a lathe.
Give two advantages of making internal threads with a single point tool on the lathe?
Large internal threads of various forms can be made and the threads are concentric to the axis of work.
In what way can speed changes be made on geared head lathes?
Levers located on the headstock can be shifted in various arrangements to select speeds.
Why should chips be broken up?
Long, stringy chips or those that become snarled on workpieces, tool post, chuck, or lathe dog are hazardous to the operator. Chip breakers and correct feeds can produce an ideal chip that does not fly off but will simply drop to the chip pan is easily handled.
How can the shift to the low-speed range be made on the belt-drive lathes that have the step cone pulley?
Low speeds are made possible by disengaging the spindle by pulling out the lockpin and engaging the back gear.
Is it possible to correctly set up a steady rest by using a dial indicator on the rotating shaft to watch for runout?
No
Should a steady rest be used on a rough surface? Explain.
No when the surface is rough, a bearing spot must be turned for the steady rest jaws.
Is the carriage moved along the ways by means of gears when the half nut lever is engaged?
No, the carriage is moved by the thread on the leadscrew when the half-nuts are engaging it.
When a taper is produced by the compound slide method, is the reading in degrees on the compound swivel base the same as the angle of the finished workpiece? Explain.
No. The angle on the workpiece would be an included angle, which is twice that on the compound setting. The angle on the compound swivel base is an angle with the work centerline.
Should you begin work immediately on a lathe that looks perfectly clean? Explain.
No. The oil on the ways may have collected dirt or grit from the air to form an abrasive mixture. The ways should first be cleaned and oiled.
If you set the quick change gearbox to 0.012 inches, is that considered a roughing feed for facing?
No. The resultant facing feed would be approximately .003 - .005 inches which would be a finishing feed.
How is a standard left hand toolholder identified?
On a left hand toolholder, when viewed from above the cutting tool end is bent to the right.
How often should a lathe be lubricated?
Once daily.
Ordinary knurls do not cut. In what way do they make the diamond or straight pattern on the workpiece?
Ordinary knurls make a straight or diamond pattern impression by displacing the metal with high pressures.
A high-speed tool bit can easily be overheated by using a glazed wheel that needs dressing or by exerting too much pressure. What does this cause in the tool.
Overheating a tool causes small cracks to form on the edge. When a stress is applied, as in roughing cut, the tool end may break off.
If cutting fluid is not used on parting tools, or chips do not clear out of the groove because of a heavy feed, what is generally the immediate result?
Parting tools tend to seize in the work, expecially with deep cuts or heavy feeds. Without cutting fluids seizing is almost sure to follow with the possibility of a borken parting tool and misaligned or damaged work.
If for some reason it becomes necessary for you to temporarily remove the tool or the entire threading setup before a thread is completed, what procedure should you follow when you are ready to finish the thread.
Picking up the thread or reseting to tool is a procedure used to posiiton a tool to existing threads.
How are tool height adjustments made on a quick change toolholder?
Quick change toolholders are adjusted for height with a micrometer collar.
Name two metric thread standard systems.
SI thread and the British Standard ISO Metric Screw Threads are two metric thread systems in use.
List five ways to eliminate chatter in a boring bar.
Shorten the bar overhang. reduce spindle speed. make sure the tool is on center use as large a diameter bar as possible without binding in the bore. reduce the nose radius on the tool apply cutting fluid to the bore use tuned or solid carbide boring bars.
Why is it not always necessary to grind a back rake into the tool?
Some toolholders provide a built-in back rake of about of about 16 degrees; to this is aded any back rake on the tool to make a total back rake that is excessive.
State the difference in use between steep tapers and slight tapers.
Steep tapers are quick-release tapers, and slight tapers are self-holding tapers.
Name two types of gibs used on lathes.
Straight gibs tapered gibs.
In what three ways are tapers expressed (measured)
Tapers are expressed in taper per foot, taper per inch, and by angles.
Briefly describe the six methods of turning a taper in the lathe.
Tapers are turned by hand feeding the compound slide, by offsetting the tailstock and turning between centers, or by using a taper attachment. A fourth method is to use a tool that is set to the desired angle and form cut the taper.
By what means should a threading tool be checked for the 60 degree angle?
The 60 degree angle on the tool is checked with a center gage or optical comparator.
If a tool turns into the workpiece and gouges it, what is usually the cause?
The T-bolt holding the tool post to the compound rest was not sufficiently tightened.
How can these angles be checked while grinding.
The angles can be checked with a tool grinding gage, a protractor, or an optical comparator.
What is the chief advantage of boring over reaming in the lathe?
The chief advantage of boring the lathe rather than reaming, is that the bore runs true with the centerline of the lathe and the outside of the workpiece (if the workpiece has been setup true with not runout). THis is not always possible when reaming bores that have been drilled, because the reamer follows the eccentricity or runout of the bore.
The better practice is to feed the tool in with the compound set a 29 degrees rather than with the cross slide when cutting threads. Why?
The chips are less likely to bind and tear off when feeding in with the compound set at 29 degrees and the tool is less likely to break.
An alignments step must be machined on a cover plate .125 in plus/minus .003 inches in depth. What procedure should be taken to face to this depth? How can you check your final finish cut?
The compound must be swung either 30 or 90 degrees so that the tool can be fed into the face of the work by a measured amount. A depth micrometer or a micrometer caliper can be used to can be used to check the trial finish cut.
Which measuring instrument is used when using a test bar?
The dial indicator.
What is the difference between a standard toolholder and a quick change toolholder?
The difference between a standard type toolholder and a quick change toolholder is the speed with which tools can be interchanged. The tools are usually fastened more securely in a quick change toolholder, and height adjustments on a quick change toolholder do not change the effective back rake angle or the cutting tool.
What should the feed rate be for roughing.
The feed rate for roughing should be one fifth to one tenth as much as the depth of cut. This should be limited to what the tool, workpiece, or machine can stand without undue stress.
What lever is shifted to reverse the lead screw?
The feed reverse lever.
Explain the difference between the fit of threads and the percent of thread.
The fit of the thread refers to classes of fits and tolerances, while percent of thread refers to the actual minor diameter of an internal thread, a 100 percent thread being full depth internal threads.
How tightly should the gibs be adjusted on the cross slide and on the compound?
The gib on the cross slide should be adjusted so it will have a slight drag, but the compound should be set up fairly tight when it is not being used.
The half-nut lever is not used to move the carriage for turning. Name its only use.
The half-nut lever is used only for threading.
What is an independent chuck, and what is it used for?
The independent chuck is a four jaw chuck in which eash jaw can move separately and independently of the others. It is used to hold odd shaped workpieces.
What precaution can be taken to prevent scoring of a finished shaft?
The jaws should be readjusted when the shaft heats up from friction, to avoid scoring. also, soft materials are sometimes used on the jaws to protect finishes.
Briefly describe the lathe spindle. How does the spindle support chucks and collets?
The lathe spindle is a hollow shaft that can have one of three mounting devices machine on the spindle nose. It has an internal Morse taper that will accommodate centers or collets.
How are tools fastened in the tailstock?
The lathe tailstock is bored with a Morse taper hole to hold Morse taper shank tools.
What is the procedure for cutting left-hand threads?
The lead screw rotation is reversed, which causes the cut to be made from the left to the right. The compound is set at 29 degrees to the left. The threading tool and lathe settings are set up in the same ways as for righty threads.
What is live center made of? How does it fit in the spindle nose?
The live center is made of soft steel, so it can be turned to true it up if necessary. It is made with a Morse taper to fit the spindle taper or speacial sleeve if needed.
Using P*.541 as a constant for Unified single depth internal threads, calculate the minor diameter for a UNC 1-8 thread.
The minor diameter equals D
When internal threads are made with a tool, what should the bore size be?
The minor diameter of the thread.
How can the number of threads per inch be checked?
The number of threads per inch can be checked with a screw pitch gage or by using a rule and counting the threads in one inch.
That other method besides turning between centers is extensively used for turning shafts and long workpieces supported by the tailstock center.
The other method is one whereby the workpiece is held in a chuck on one end and in the tailstock center on the other end.
Explain the difference between the threads per inch and the pitch of the thread.
The pitch is the distance between a point on a screw thread to a correspoinding point on the next thread measured parallel to the aixs. Threads per inch is the number of threads in one inch.
When is the proper time to use the carriage handwheel?
The quick approach and return of the tool; this is used for delicate work and when approaching a shoulder or chuck jaw.
If the swivel base is set to a 35 degree angle at the cross-slide centerline index, what will the reading be at the lathe centerline index.
The reading at the lathe centerline index would be 55 degrees which is the complimentary angle.
The jaws of the follower rest are usually 1 0r 2 inch to the right of the tool on a setup. If the workpiece happens to be smaller than the dead center or tailstock spindle, how will it be possible to bring the tool to the end of the work to start a cut without interference by the follower rest jaws.
The shaft is purposely made of 1 to 2 in longer, and an undercut is machined on the end to clear the follower rest jaws.
Give one disadvantage of the sharp V thread
The sharp V thread can be easily damaged during handling if it is dropped or allowed to strike against a hard surface.
What happens when you drill too deeply with a center drill?
The sharp edge provides a poor bearing surface and soon wears out of round, cuasing machining problems such as chatter.
What is the function of the side and back rakes?
The side rake directs the chip flow away from the cut and also provides for a keen cutting edge. The back rake promotes smooth chip flow and good finishes.
Explain the purpose of the side and end relief angles.
The side relief allows the tool to feed into the work material. The end relief angle keeps the tool end from rubbing on the work.
What would the spacing or distance between tool marks on the workpiece be with a .010 in feed.
The spacing would be 0.010 inches, as the tool moves that amount for each revolution of the spindle.
Name the spindle nose types.
The spindle nose types are the threaded long taper key drive and the camlock.
How fast should the spindle be turning for threading?
The spindle should be turning slowly enough for the operator to maintain control of the threading operation, usually about one fourth of turning speeds.
How is the steady rest set up on a straight finished shaft when it has centers in the ends?
The steady rest is placed near the tailstock end of the shaft, which is supported in a dead center. The steady rest is clamped to the lathe bed, and the lower jaws are adjusted to the shaft finer tight. The upper half of the frame is closed, and the top jaw is adjusted with some clearance. The jaws are locked and lubricant is applied.
What is the most practical and convenient way to check internal and external tapers when they are in the lathe?
The taper plug gage and the taper gage are the simplest and most practical means to check a taper.
Should the point of the tool be set above, below, or at the center of the spindle axis when taking a facing cut?
The tool should be on the center of the lathe axis.
What are the two types of taper attachments, and what are their advantages over other means of making a taper?
The two types of taper attachments are the plain and the telescopic. Internal and external and slight to fairly steep tapers can be made. Centers remain in line, and power feed is used for good finishes.
What is a universal chuck, and what is it used for?
The universal chuck is most often a three jaw chuck, although these chucks are made with more or fewer jaws. Each jaw moves in or out by the same amount when the chuck wrench is turned. THey are used to hold and quickly center round stock.
Why would thread cuts with a hand die in a tahte not be acceptable for using on a feed screw with a micrometer collar?
The variations in pitch of the hand cut threads would cause the micrometer collar to give erroneous readings. A screw used for this purpose and for most machine parts must be threaded with a tool guided by the leadscrew on the lathe.
Explain the speed shifting procedure on the variable speed drive.
The varidrive is changed while the motor is running, but the back gear lever is shifted only with the motor off.
What happens to the workpiece when the centers are out of line?
The workpiece becomes tapered.
Describe the procedure used to produce drilled holes on workpieces in the lathe with minimum oversize and runout.
The workpiece is center spotted with a center drill at the correct rpm, and if the hole is to be more than 3/8 in in diameter, a pilot drill is put through. Cutting fluid is used. The final size drill is put through at a slower speed.
What happens to the workpiece when the tailstock is offset toward the operator?
The workpiece is tapered with the small end at the tailstock.
The sliding gear shifter lever on the quick change gearbox are used for just two purposes. What are they?
These levers are used for selecting feeds or threads per inch for threading.
Micrometer collars are attached on the crossfeed handle and compound handle. In what ways are they graduated?
They are graduated in English units. Some metric conversion collar are being made and used that read in both English and metric units at the same time.
By what means is thread relief on external grooves produced?
Thread relief and external grooves are produced by specially ground tools similar to internal grooving ools except that they ahve less end relief. Parting tools are often used fo making external grooves.
Explain the differences between through boring, counterboring, and boring blind holes.
Through boring is making a bore the same diameter all the way through the part. Counterboring is making two or more diameters in the same bore, usually with a 90 degree or square internal shoulders. Blind holes are bores that do not go all the way through.
What is a major reason for thread allowances and classes of fits?
To allow tolerancing of external and internal threads to promote standardization and interchangeability of parts.
Why were quick change toolholders developed?
To increase rigidity and thus yield greater production.
When making internal right hand threads, in which direction should the compound be swiveled?
To the left of the operator.
How are tool height adjustments made on a standard toolholder?
Tool height adjustments on a standard type toolholder are made by swiveling the rocker in the tool post ring.
How are tool height adjustments made on a turret type toolholder?
Tool height on turret toolholders is adjusted by placing shims under the tool.
How does the toolholder overhang affect the turning operation?
Toolholder overhang affects the rigidity of a setup; too much overhang may cause chatter.
Which standard toolholder would be best used for turning close to the chuck?
Turning close to the chuck is usually best accomplished with a left hand toolholder.
How do form tools work?
Unlike single point tools, form tools produce their shape by plunging directly into the work.
A tool that has been reground too many times on the same place can form a chip trap. Describe the problems that result from this.
When a "chip trap" is formed by improper grinding on a tool, the chip is not able to clear the tool; this prevents a smooth flow across the face of the tool. The result is tearing of the surface on the workpiece and possibly a broken tool.
When is a tailstock turret used?
When a series of repeat tailstock operations is to be performed on several different workpieces, a tailstock turret should be used.
If a knurl is producing a double impression, what can you do to make it develop a diamond pattern?
When knurls produce a double impression, they can be readjusted up or down and moved to a new position. Angling the toolholder 5 degrees may help.
When should a steady rest be used?
When workpieces extend from the chuck more than four or five workpiece diameters and are unsupported by a dead center; when workpieces are long and slender.
By what means is the measuring done when checking taper by taking a cut?
With a micrometer. The tailstock is set over with a dial indicator.
How is the dead center correctly adjusted?
With no end play in the workpiece and the bent tail of the lathe dog free to move in the slot.
Name three methods of aligning the centers.
Witness mark on the tailstock Test bar Taking a light cut on a workpiece and measuring.
On which type of plate are workpieces and fixtures mounted? How is it identified?
Workpieces and fixtures are mounted on faceplates. These are identified by their heavy construction and the T-slots. Drive plates only have slots.
How can you avoid chatter when cutting off stock with a parting tool?
You can avoid chatter when cutting off with a parting tool by maintaining a rigid setup and keeping enough feed to produce a continuous chip if possible.
How can you avoid porducing a knurled surface on which the metal is flaking off?
You can avoid producing a flaking knurled surface by stopping the knurling process when the diamond points are almost sharp. Also, lubricate.
How can you know if the lathe you are using is calibrated for single or double depth?
You can test with a rule and a given slide movement such as .125 or .25o inches. If the slide moves half that distance, the lathe is calibrated for double depth and reads the same amount as that taken off the diameter.
How are Unified and metric thread forms simlar?
both are 60 degree forms.
What does 1/2-20 UNC 2A describe?
diamter of 1/2 inche, 20 threads per inch, and Unified coarse series external thread with a class 2 thread fit
Give two methods of checking an internal thread for size.
thread plug gage shop made plug gage mating part.
What factors tend to promote or increase chip curl so that safer chips are formed?
Coarser feeds, deeper cuts, and smaller rake angles all tend to increase chip curl. Chip breakers also make the chip curl.
Name on advantage of using steel spring collets. Name one disadvantage.
Collet chucks are accurate workholding devices. Spring collets are limited to smaller material and to specific sizes.
What chuck types make possible the frequent adjusting of chucks so that they will hold stock with miniumum runout?
Combination chucks and Adjust-Tru three jaw chucks
Cutting speeds for reaming are (twice,half) that used for drilling.
Cutting speeds for reaming are half that used for drilling; feed used for reaming are twice that used for drilling.
Name three kinds of centers used in the tailstock and explain their uses.
Dead centers are hardened 60 degree centers that do not rotate with the work but require high pressure lubricant. Ball bearing centers turn with the work and do not require lubricant. Pipe centers turn with the work and are used to support tubular material.
Machine reamers produce a better finish than is obtained by boring. How can you get an even better finish with a reamer?
Hand reamers produce a bettter finish than machine reaming.
How should the ways and slides be cleaned?
Heavier chips should be removed with a brush; never use an air jet. The ways should be wiped clean with a cloth and gently oiled.
List the advantages to using high speed steel for tools.
High speed steel is easily shaped into the desired shape of cutting tool. It produces better finishes on low speed machines and on soft metals.
