Engine Room Tools Part 1

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Listed by Name How to Find Ship Info Introduction Support HNSA:

Folks,

Engine Room Tools, 1949, is a training manual that focuses on the correct use of

tools aboard ship. It is noteworthy because it includes tools that are specific to

the maritime trades.

In this online version of the manual we have attempted to keep the flavor of the

original layout while taking advantage of the Web's universal accessibility.

Different browsers and fonts will cause the text to move, but the text will remain

roughly where it is in the original manual. In addition to errors we have

attempted to preserve from the original, this text was captured by a

combination of optical character recognition and human typist. Each method

creates errors that are compounded while encoding for the Web. PPlease report

any typos, or particularly annoying layout issues with the Mail Feedback Form

for correction.

Richard Pekelney

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Table of Contents

Introduction

Part I, Hand Tools

Part II, Fasteners, Hoists, etc.

Part III, Measuring Instruments

2020

COPYRIGHT 1949 BY

MAST MAGAZINE ASSOCIATION

PRINTED IN U.S.A.

Prepared by the Staff

of the

UNITED STATES

MARITIME SERVICE INSTITUTE

Acknowledgment

The staff of the United States Maritime Service Institute wishes to acknowledge the

valuable aid given by the following organizations in granting permission to use

material from their publications.

National Board of Fire Underwriters

Snap-on Tools Corporation

Herman H. Sticht Co., Inc.


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1

ENGINE-ROOM TOOLS

1. This text is divided into three parts. Each part constitutes one lesson and isfollowed by its respective examination. The correct procedure is to study Part 1,

and complete and send in the examination for that part. Then study and

complete Parts 2 and 3 in the same way.

Except for certain special tools that are taken up later in connection with the

equipment on which they are used, these lessons describe the hand tools

commonly worked with in the engineering department of a ship, and explain

certain precautions that should be taken in using and caring for such tools. In

order that the coverage will be as complete and helpful as possible, the lessons

also include a description of some tools that might not be found aboard ship,

but that would be encountered in shipyards, machine shops, and other places

where maintenance and repair work is done.

The information in the lessons is extremely important to all who desire to be

completely familiar with and well trained in the knowledge and uses of hand

tools. It will aid the beginner, for example, to identify and locate the right tool for

a job and help him to perform his work more efficiently. It should also contain

much of interest to engineering personnel who have picked up their knowledge

of tools more or less by chance as their work required various tools to be used.Even engineers with long experience may gain valuable information that they

had not known about previously.

The Tools lessons will be found quite elementary in places, since they are

prepared so as to be suitable for the beginning student, as just explained. They

should be studied carefully, however, as this will enable all students to practice

the art of study (which they may not have been doing recently) and will help

them to master the more difficult engineering principles that follow in later

lessons.

2. Good tools are essential if a mechanic is to do his best work quickly, properly

and accurately. Without the proper tools and

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the knowledge of how to use them, time is wasted, efficiency is reduced, and the

person doing the work may injure himself.

Good tools are carefully made, and must be handled properly if they are to work

and last as intended. They cannot take rough usage. This is especially important

aboard ship where it may be .impossible to procure a replacement when

needed.

In general, every tool should be given. its own place on a tool rack or tool board,

or in a tool box. Some tools should be kept close by the machine for which they

are designed and on which they are used. Other tools must be stored in the tool

room. Tools should be cleaned after being used, should be oiled, in some cases,

to prevent rust, and should then be returned to their respective places.

When tools are taken care of systematically, it is much easier to find the tool


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needed. This is important, especially in an emergency. It is also possible to check

more readily to see whether any tools are missing, and, if so, which ones they

are.

A good mechanic will take care of his tools, as valuable time and possibly lives

may depend on the accomplishment of a piece of work quickly and accurately.

He will keep cutting tools sharp, grind them, if necessary, when through usingthem, and store them so that their edges will not be damaged or dulled by

contact with each other or with other hard objects. He will handle delicate

measuring instruments with care, and will not keep them where they might be

damaged by heavy tools.

When work is being done, the necessary tools should be kept within easy reach,

but not where they can fall and be damaged, or where they may fall and injure

someone, as might occur from an upper level in the engine room. It is advisable

to spread canvas along a grating, if tools are to be placed on it, or if work isbeing carried on where tools might drop and fall through it. Openings in the

engine or other equipment being worked on should be covered or plugged to

prevent tools, nuts, bolts, etc., from accidentally falling through the openings.

Such objects within the cylinder or crankcase of an engine, and not observed

and removed before starting up, can cause considerable damage.

Tools should never be placed on the finished parts of a machine, on the ways of

a lathe, for example. Sharp tools should not be carried in the pockets of clothing

or left protruding from work benches, as they may tear or puncture objects with

which they come in contact, including the workman.

3

Some tools can be used for several purposes, but using the wrong tool may ruin

not only it, but the work as well. If a screwdriver is used as a prying tool, it may

bend or break. If a chisel is used instead of a wrench, an important part of the

machinery may be scarred or broken.

The way in which tools are handled, and the care given to them, indicates the

quality of workmanship and the kind of engineering to be expected in your

department.

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ENGINE-ROOM TOOLS, PART 1

3. Hammers.-The hammer is a very simple striking tool, being just a weightedhead and a handle to direct its course. Several types of hammers are shown in

Fig. 1.


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FIG. 1. TYPES OF HAMMERS.

The ball-peen hammer, often termed the machinist's hammer, is a very useful tool

aboard ship. The headof the hammer is made of hardened steel. The handleis

of hickory or other hardwood. The flat portion of the head is called theface, and

the other end is known as the peen, the latter being used for heading rivets and

similar peening or drawing operations. The hole for the handle is the eye.

Ball-peen hammers are classed according to the weight of the head without the

handle. They vary in size from 4 ounces to 2 pounds, three popular sizes being

the 6-ounce for light work, the 12-ounce for general utility, and the 16-ounce for

heavy work.

The straight-peen hammeris used for spreading or drawing out metal in line with

the handle, while the cross-peen hammeris used for the same operation at right

angles with the handle. The claw hammeris used for driving and pulling nails.

Hammers with heads made of soft material, such as lead,

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copper, babbitt, rawhide, wood, plastic, etc., are called soft hammers. Soft

hammers are generally used where a steel hammer might mar or injure the

work.

4. The eye in the hammer head is made with a slight taper in both directions

from the center. After the handle is inserted in the head, a steel wedge is driven

into the end. This expands the taper of the handle in the eye and wedges the

handle in both directions. If the wedge starts to come out, it should be driven in

again. If the wedge comes out and is lost, it must be replaced before continuing

to use the hammer. Never work with a hammer having a loose head. A loose

head will eventually fly off, and may injure someone.

When using a hammer, it should be held near the end of the handle with the

face of the hammer parallel to the work. A grip just tight enough to control the

blow is best. The correct way to hold a hammer is shown in Fig. 2.


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FIG. 2. How TO HOLD A HAMMER.

Keep the hands and the hammer handle free from grease and oil, otherwise the

hammer may slip from the grasp. It should also be remembered that oil or

grease on the hammer face may cause it to slip off the work and lead to a

painful bruise. Do not ruin the hammer handle by using it for pounding or

prying purposes.

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5. Sledges.-Sledges, or sledge hammers, are used for heavy work. They can be

procured in both single-face and double-face types, a double-face sledge being

shown in Fig. 3, and vary in weight from 4 to 20 pounds. The handles vary in

length up to 36 inches.

FIG. 3. SLEDGE.

6. Screwdrivers.-Screwdrivers have three main parts: the handle, which is

gripped by the user; the shank, which is the steel portion extending from the

handle; and the blade, which is the end that fits into the slot of the screw.

Several types of screwdrivers are shown in Fig. 4.

Fig. 4. TYPES OF SCREWDRIVERS.


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The standard screwdriveris used for most ordinary work and comes in a variety

of sizes. The blade must have sharp corners and fit the slot in the screw closely;

otherwise it is likely to slip and damage the slot. It is also important that a

screwdriver be held firmly against the screw to prevent it from slipping and

injuring the worker or the work.

The offset screwdrivermakes work possible in tight corners where the straight

type will not enter. It has one blade forged in line with the shank, and the other

blade at right angles to the shank. With such an arrangement, first one end of

the screwdriver

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can be used and then the other, changing ends after each swing, thus working

the screw in or out of the threaded hole.

The Phillips-type screwdriveris made with a specially shaped blade to fit

Phillips-type cross-slot screws. The heads of these screws have two slots that

cross in the center. This checks the tendency of the screwdriver to slide out of

the slot onto the finished surface of the work.

The ratchet screwdriveris used to drive or remove small screws rapidly.

Some screwdrivers have handles made of insulating material, and are useful

when electrical work is being done. When a screwdriver with an insulated

handle is not available, the handles of other screwdrivers can be insulated by

wrapping them with tape.

While the screwdriver shown in Fig. 4 has a round shank, some heavy-duty

screwdrivers are made with a square shank, the construction enabling the

torque of the screwdriver to be increased by applying a wrench to the square

shank. A heavy-duty screwdriver, also a special screw-holding screwdriver, are

shown in Fig. 5.

FIG. 5. SPECIAL SCREWDRIVERS.

FIG. 6. CORRECTLY GROUND TIP.

7. The tip of a screwdriver blade should be ground so that the sides of the blade

are parallel, and the blade sides should


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gradually taper out to the shank body, as shown in Fig. 6. If the end of the blade

is damaged, it can be made serviceable again by means of a grinding wheel. First

grind the tip straight and at a right angle to the shank. After the tip is ground

square, dress off from each face, a little at a time. Keep the faces parallel for a

short distance or have them taper in a slight amount. Never grind the faces so

that they taper to a sharp edge at the tip.

Do not use a screwdriver to check an electrical circuit where the amperage is

high. The electrical current may be strong enough to form an arc and melt the

screwdriver blade. It is also bad practice to try to turn a screwdriver with a pair

of pliers or to use it as a chisel.

Do not hold work in the hand while using a screwdriver. If the blade slips, it can

cause a bad cut. Hold the work in a vise, secure it with a clamp, or stand it firmly

on a solid surface. If such precautions are impossible, take care to have no part

of your body in front of the screwdriver blade. That safety rule applies to any

sharp or pointed tool.

8. Pliers.-Several commonly used types of pliers are shown in Fig. 7.

FIG. 7. TYPES OF PLIERS.

Side-cutting pliersare used principally for holding and bending thin material or

for cutting wire.Adjustable combination pliershave a slip joint that permits the

jaws to be opened wider at the

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hinge for gripping large diameters. They are used principally for holding and

bending flat or round stock. The various lengths and shapes offlat-nose,

round-nose, and needle-noseor long-nose pliersmake it possible to bend or form

metal into a variety of shapes, to hold objects in tight spots, and to make

delicate adjustments. Needle-nose pliers are helpful when recovering a washer

or nut from a place where it is hard to reach. They also make it easier to remove

and install such things as valve-spring retainer pins. They are not of heavyconstruction, however, and should not be forced beyond their capacity. Their

jaws are comparatively weak, and are easily broken or sprung.


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Avoid using pliers on a hardened surface, as such use dulls the teeth and causes

pliers to lose their gripping power. Do not use pliers for loosening or tightening

nuts, as the flats of the nuts will become damaged.

Diagonal-cutting pliershave short jaws with blades at a slight angle, as shown in

Fig. 8. This tool is valuable when removing and replacing cotter pins, and can beused not only to cut the

FIG. 8. DIAGONAL-CUTTING PLIERS.

pins to the desired length but to spread the ends after the pins are in place.

They are also handy for cutting the soft wire which is passed through small

holes in nuts and bolt heads to "safety" them, or prevent them from working

loose. When diagonal-cutting pliers are used, the cut should be made with the

throat of the jaws, not with the points, as the latter use would increase the

tendency to spring the jaws apart. Once the jaws are sprung, it is difficult to cut

fine wire.

9. Nippers.-Nippers resemble pliers, but are used only for cutting, not for

holding. Various types can be used for cutting wire, rod, nails, rivets, and bolts.

For light work on soft metals the

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FIG. 9. NIPPERS.

nippers shown at A, Fig. 9, would be used. They must not be overstrained,

however, as their thin cutting edges are easily nicked and dented. For heavier

work, the nippers shown at B are used. This type has replaceable blades, a

strong joint, and a short fulcrum that provides plenty of leverage. Nippers

should not be used to cut such material as drill rod or piano wire.

10. Shears and Snips.-Hand shears, or snips, are used for cutting sheet metal of

various kinds and thicknesses. Several commonly used types of these tools are

shown in Fig. 10.

Straight snipshave blades that are flat and straight on the inside surfaces. They


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are designed for straight cutting but can also be used on large outside curves. It

is difficult, however, to cut circles and arcs of small radii with straight snips, the

scroll-pivoter snipsbeing more suitable for such purposes. The blades of the

latter tool are approximately at right angles and provide clearance for following

curves.

Circular snips, with their curved blades, will handle all except the smallest curves.They are available for either right-hand or left-hand use. Hawksbill snipscan cut

inside and outside circles of small radii. Their narrow curved blades are beveled

enough to permit sharp turns without buckling the material. It should be noted,

however, that both the circular and hawksbill snips must be used carefully, as

their blades are easily sprung out of contact.

Trojan snipsare slender-bladed snips used for straight or curved cutting. The

blades are small enough to permit sharp turns, and will also cut outside and

inside curves. They are sometimes known as combination snips. There are alsospecial snips designed for stainless steel and Monel metal. They resemble

Trojan snips, but

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FIG. 10. SHEARS AND SNIPS.

have inlaid alloy cutting edges. They are identified by the words "For Stainless


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Steel Only" stamped on them.

11.Snips do not remove any of the metal when making a cut, but work with a

shearing action that tends to roughen the edges of the material. Because of this

it is better not to cut exactly on the layout line. After the cut is made, the edge

can be dressed with a file. There is no set rule for the amount to be allowed for

dressing, but the thinner and softer the metal; the closer the cut can be made tothe layout line.

12

When cutting from the edge of a large sheet, it is advisable to cut from the

left-hand side. This allows the small piece being removed to curl out of the way

of the snip blades as the cut is made. Never cut with the full length of the

blades. If the points of the snips are allowed to come together, they will tear themetal as the cut is completed. Stop each cut about 1/4 inch before the ends of

the blades have been reached, and start a new cut with the throat, which is that

part of the angle between the blades nearest to the pivot pin. Cutting in this

way, especially with heavy metal, is easier on the snips and is not so likely to

spring the blades. When the blades are sprung, hand snips are useless. Care

should also be taken to see that snips are not used to cut wire, bolts, rivets, or

nails, as such use will dent or nick the cutting edges.

Snip blades can be reground when they become dull. To do so, the blades

should be taken apart and the cutting edges ground to an included angle of 85.

Blade tension is adjusted by turning the nut on the pivot bolt, or pin, holding the

blades just tight enough to remain in any position in which they are placed. Oil

the pivot, spread a thin film of light oil on the blades to prevent rust, and keep

the snip blades closed when they are not in use.

When cutting large sheets of metal, it is helpful to lay the metal on the bench

and make the cut with the lower handle of the snips resting on the bench top.

This lessens the strain on the worker's hand and allows him to use his weight to

advantage.

12. Bolt Cutters.-For heavy-duty cutting jobs, a bolt cutter, shown in Fig. 11, is

used. These tools are made in several sizes,

FIG 11. BOLT CUTTER.

from 18 to 36 inches in length, the larger ones being used to cut mild steel bolts

and rods up to 1/2 inch in diameter. Bolt cutters usually have special replaceable

jaws of extra-hard metal alloys;

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the jaws therefore are brittle and will break before they will bend or dent. Any

twisting motion should be avoided when they are used. The tool shown in Fig.

11 has set screws which enable the relative positions of the blades to be

adjusted, if they should fail to meet properly after having been sharpened.

Fig. 12. PUNCHES.

13. Punches.-Several types of punches are shown in Fig. 12. These tools may be

used for a variety of jobs, but the correct punch for the job should always be

selected.

A center punchis used to make a starting mark for a drill when holes are to be

drilled in metal. If the center punch mark is not made, the drill will wander or

"walk away" from the desired center. The center punch point should be taper-

ground to an angle of about 90. Never use a center punch to remove a bolt or

pin, as the sharp point will act as a wedge and tend to tighten the bolt or pin in

the hole.

Prick punchesare generally used for marking centers and lines in layout work.

Starting punches, sometimes called drifts, have a long taper

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from the tip to the body. They are made that way to withstand the shock of

heavy blows. They may be used for knocking out rivets after their heads have

been cut off, or for freeing pins or bolts from their holes. To start a bolt or pin

that is extremely tight, use a starting punch that has a point diameter only

slightly smaller than the diameter of the object that is being removed.

After a pin or bolt has been loosened or partially driven out, it may be found

that the starting punch is too large to finish the job. Apin punchcan then be

used, as it is designed to follow through the hole without jamming. Both startingpunches and pin punches must have flat ends, never edged or rounded ones.


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The alining, or lining up, punch is used to line up corresponding holes in adjacent

parts, for example when working on engines that have pans and cover plates.

A special punch, not shown in the illustration, is known as the soft-faced drift.

This drift is made of brass or fiber and is used to remove such things as wrist

pins. It is heavy enough to resist damage to itself, but soft enough not to injurethe finished surfaces of the parts being removed.

When it is necessary to make gaskets of rubber, cork, leather, or composition

materials, agasket punch, one type of which is shown in Fig. 12, is used to cut the

bolt holes. This punch comes in sizes to accommodate standard bolts and studs.

The cutting end is tapered to a sharp edge so as to produce clean, uniform

holes. To use the gasket punch, place the gasket material on a piece of wood

that has been cut across the grain, so that the cutting edge of the punch will not

become broken or dulled. Then hold the punch against the gasket and strike it

with a hammer, driving the punch through the gasket where holes are required.

14. Vises.-Two types of vises usually found aboard ship are shown in Fig. 13. The

machinist's viseis a heavy-duty holding tool with parallel jaws and either a fixed

or swivel base. It should be used only for holding material when hacksawing,

filing, drilling, tapping, reaming, etc. It should not be used as an anvil. The utility

viseis satisfactory for general work and is designed for a variety of uses. It has a

small anvil and anvil horn as part of the back jaw. The anvil surface is broken by

a small hole into which the hardiefits. The hardie is the small tool shown in Fig.

13, just above the anvil of the utility vise. It is used for cutting heavy wire andsmall rods and bars. Pipe jaws, as shown in the illustration, can

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FIG. 13. VISES.

be mounted inside the regular jaws for holding pipes and rods. Soft jaws, which

are inserts of brass, copper, or other soft metal, can be made from scrap metal

and mounted on the jaws of a vise when the surface of the work must be

protected.

15. For satisfactory operation, keep the vise clean, oiled, and in good general

condition. The screw that operates the movable jaw should be lubricatedfrequently with light grease or heavy cylinder oil. The slide should be wiped

clean every day and light machine oil spread over it. Never oil the swivel joint of


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a vise, however, as its holding power would be impaired. Always tighten and

loosen a vise by holding the handle with the hands, applying the weight of the

body to secure the turning pressure. Do not hit the vise handle with a hammer.

When the vise is not in use, the jaws should be brought lightly together, with the

handle in the vertical position.

Be sure to keep fingers clear of the jaws when clamping work in the vise, anduse care to keep them from being pinched between the end of the handle and

the head of the screw, the latter accident being a very common one. When

holding heavy work in a vise, it is advisable to place a block of wood or metal

under the work as a prop to prevent it from sliding down and perhaps falling to

the floor or on the foot. Care should also be exercised to see that the vise is not

opened beyond the limit of the screw,

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as the movable jaw may drop off and the user suffer serious injury. If it is

necessary to pound against metal parts held in a vise, be sure to pound against

the back jaw, as it is heavier than the front jaw and strong enough to absorb the

shock of the blows.

16. Clamps.-When a vise is not available, a clamp can be used to hold pieces of

material together while they are being worked on. Clamps of this type are

shown in Fig. 14. A different kind of clamp is often used to make a temporary

fastening in the engine room when it is desired to lift or take a strain on some

object. To do so, the clamp is securely fastened to a convenient beam, as shown

in Fig. 15, and a line or small hoist then suspended from the clamp.

FIG. 14. SCREW CLAMPS.

17. Wrenches.-Fundamentally, the wrench is a tool for exerting a twisting strain,

as in turning bolts and nuts. As the majority of nuts and bolt heads are

hexagonal, or 6-sided, many wrenches are specially designed to fit hex-heads

and hex-nuts.


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18. Open-end Wrenches.-Solid, nonadjustable wrenches with

17

FIG. 15. BEAM CLAMPS.

openings in one or both ends are called open-end wrenches. A set of these tools

is shown in Fig. 16. Open-end wrenches with small openings are usually shorter

than wrenches with large openings, thus proportioning the lever advantage of

the wrench to the size of the work and helping to prevent breakage of the

wrench or damage to the bolt or stud.

FIG. 16. SET OF OPEN-END WRENCHES.

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The size of an open-end wrench is usually stamped on the face, and denotes the

width of the opening between the jaws of the wrench. To determine the size of

bolt head or nut that the wrench will fit, subtract 1/8 inch from the wrench size

and then multiply by 2/3. For example, a 1 5/8-inch wrench will fit the nut of a

1-inch bolt, as shown by the following.


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1 5/8 - 1/8 = 1 1/2

1 1/2 X 2/3 = 1 inch. Ans.

When the size of the nut or bolt is known and it is desired to find the wrench to

fit it, multiply the nut size by 3/2 and add 1/8 inch. For example, for a 3/4-inch

nut, the width of the wrench opening would be computed as follows:

3/4 X 3/2 = 9/8

9/8 + 1/8 = 10/8 = 1 1/4 inches. Ans.

19. Open-end wrenches may have their jaws parallel to the handle, or at angles

up to 90, the average being about 15. A wrench with 15 angles and a wrench

with a 90 angle are shown in Fig. 17.

The jaws of open-end wrenches are placed at an angle in order to make it easier

to work with the wrenches in close quarters, as it is frequently necessary to

tighten or loosen a nut where there is very little space in which to swing a

wrench. The procedure

FIG 17. OPEN-END WRENCHES.

19

known asfloppingthe wrench is therefore used, that is, turning the wrench over

so that the other face is down after each stroke. In a situation such as shown in

Fig. 18, view (1), it is not possible to place the jaws of the wrench on the nut

when held in the position illustrated. However, with the wrench turned over, asshown in views (2) and (3), it is possible to apply the wrench


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FIG. 18. USE OF OPEN-END WRENCH.

to the nut and turn it in the direction for loosening. Although not shown in the

illustration, the wrench will have to be turned over at the end of each swing.

When a wrench has jaws at the 15 angle, it is possible, by means of the flopping

technique, to turn a hex-nut even though the swing of the wrench is limited to

30.

There are special open-end wrenches, such as tappetwrenches, which are very

thin and have extra long handles. They are used to adjust the valves of small

internal combustion engines, and must be handled with care. A set of ignition

wrenches is used in caring for engine electrical systems.

Aboard ship, heavy-duty open-end wrenches are often needed in order to

handle large nuts. These are known as drive-upwrenches. In some cases one

man will hold the wrench on the nut, keeping a firm pulling strain on it, while

another person

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strikes the wrench with a sledge hammer. Some wrenches are so large that a

pulling strain is taken with a chain fall, and the wrench is then struck by a heavy

ramsupported by a block and tackle and wielded by several men.

20. When selecting an open-end wrench, be sure that the wrench jaws fit the nut

or bolt head. If the wrench opening is too large, the wrench will slip around the

nut and round off the corners of the hex-faces, possibly springing the jaws of

the wrench at the same time. Also, always make sure that the wrench is seated

firmly on the flats of the nut.

When it is necessary to exert considerable force on a wrench, it is usually

advisable to pull instead of push. Pushing on a wrench may be dangerous, as a

sudden loosening of the nut can lead to striking some part of the body against

the machine being worked on. Whenever considerable effort is to be applied to

a wrench, make sure that the footing is secure and take precautions against

stumbling, slipping and falling.


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Some wrenches are designed for a particular job, to tighten the nuts on the

handhole and manhole plates of a boiler, for example. Since the leverage of

such a wrench is proportioned to the strength of the studs and other material

being tightened, use the correct wrench, and do not add to its leverage by

slipping a piece of pipe over the end. Exceeding the designed leverage in this

manner can cause stripped threads and broken studs, nuts and other parts, andlead to the breakdown of a piece of machinery and injury to personnel.

21. Adjustable Wrenches.-A handy all-round wrench for light work is the

adjustable open-end wrench, such as shown in Fig. 19. One jaw of this wrench is

fixed; the other jaw is moved along a slide by a screw adjustment, the angle

between the jaw opening

FIG. 19. ADJUSTABLE OPEN-END WRENCH.

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and the handle being 22 1/2. An adjustable wrench will not stand the hard

usage of an open-end wrench and must be used very carefully. It is important

that its jaws be closely adjusted to fit the nut, and it should always be used so

that the force of the pull comes on the solid, or stationary, jaw, as shown in Fig.

19.

Monkey wrenches, one of which is shown in Fig. 20, are useful in many instances,

when tightening or loosening pipe unions, for example, or where the exact size

of open-end wrench is not available. When using monkey wrenches, take thesame precautions

FIG. 20. MONKEY WRENCH.

as with adjustable wrenches. Always have the jaws point in the direction of the

pull.

22. Box-end Wrenches.-Some box-end wrenches have 6 inside faces, or notches,

but most of them have 12 notches, as shown in Fig. 21, this wrench being known

as a 12-pointor double-hexbox wrench.

FIG. 21. BOX-END WRENCH.


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There is little chance for a box-end wrench to slip off the nut, and it cannot

spread on the nut and cause undue wear. Because the sides of the box opening

are comparatively thin, the wrench is suitable for turning nuts that are hard to

reach with an open-end wrench. An offsetbox-end wrench is shown in Fig. 22.

When using box-end wrenches, and there is insufficient room to turn thewrench in a complete circle, it is necessary to lift it off the nut after each pull and

then place it back on in another position. In this case, therefore, after a tight nut

is started, it can often be unscrewed much more quickly with an open-end

wrench

22

FIG. 22. OFFSET BOX-END AND COMBINATION WRENCHES.

than with a box wrench. A combination wrench, as shown in Fig. 22, is therefore

helpful, using the box end for starting the nuts when loosening them, or for final

tightening, and the open end for faster turning.

23. Socket Wrenches.-Two typical one-piece socket wrenchesare shown in Fig.

23. These are heavy-duty wrenches, made with 4 inside faces for square nuts or

with 6 inside faces for hex-nuts. This type of socket wrench, however, does not

have the wide

FIG. 23. ONE-PIECE SOCKET WRENCHES.

adaptability of detachable socket wrenches, a set of which contains an

assortment of individual sockets of various sizes made to fit different handles.

There are several types of handles, such as the T-handle, ratchet handle,screwdriver-grip handle, and speed handle, the latter resembling a carpenter's

brace. A ratchet


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23

FIG. 24. SOCKET WRENCHES.

handle, a T-handle, an extension, and a 12-point socket are shown in Fig. 24.

To use a detachable socket wrench, select a socket that fits the nut, place the

socket on the projecting lug of the handle and then place the socket over the

nut. The socket is held on the lug by a small friction catch that engages when the

socket and lug are forced together.

The ratchet handle permits the wrench to be turned without removing it from

the nut, a gear shift often being incorporated in the construction so that the nut

can be turned in either direction without turning the wrench over.

24. Torque Wrench.-One type of torque wrenchis shown in Fig. 25. This tool is

used as a socket wrench handle in order to exert the desired amount of strain

when tightening nuts and bolts. As the torque wrench is pulled, the scale or dial

of the tool

FIG. 25. TORQUE WRENCH.

24

indicates how great a twist, or torque, is exerted, and the pull is continued until

the desired reading is reached. This is very important in many cases, enabling a

workman to tighten the bolts of a crankpin bearing, for example, to the exact

tension specified by the manufacturer of the engine, and to make sure that

cylinder-head nuts are all evenly tightened according to instructions. If nuts are

tightened with too much force, the bolts may break. In the case of a crankpinbolt, for example, with the engine in operation, such breakage would probably

cause serious damage. If cylinder-head nuts are tightened unevenly, stresses


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may be set up that lead to cracking of castings, stripping of threads, etc.

The accuracy of a torque wrench reading depends in part upon the condition of

the threads of the bolt or nut and on the lubrication of the threads. Readings are

more accurate when the threads are in good condition and well lubricated.

25. Spanner Wrenches.-Several types of spanner wrenchesare shown in Fig. 26.The hook spannerworks on a round nut which has a series of notches cut in its

outer surface. The hook, or lug,

FIG. 26. SPANNER WRENCHES.

25

is placed in one of the notches and the handle turned to loosen or tighten the

nut. An adjustable spanneris designed to fit nuts of various diameters. Pin

spannershave a pin instead of a lug, the pin fitting a round hole in the edge of

the nut. U-shaped spannershave either lugs or pins that fit in notches or holes in

the top of the nut or screw plug.

26. Special Wrenches.-Several special wrenches are shown in Fig. 27. The

Allen-type wrenchhas a 6-sided shaft that fits into the


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FIG. 27. SPECIAL WRENCHES.

hex-shaped recess of set screws and cap screws. The Bristo-typewrench has a

number of splines on the shaft, the design tending to reduce spreading. The

Spintite wrenchhas a hollow shaft with a hex- head, and is used for electrical

work. It should therefore have an insulated handle. The dial-wrenchis a special

wrench for removing and replacing the dials of electrical and computing

equipment.

26

FIG. 28. HACKSAWS.

27. Hacksaws.-The hacksaw is a tool used to saw metal, and consists of a

handle, frame and blade. Thepistol-griptype, shown in the upper part of Fig. 28

is adjustable to take various blade lengths. The straight-handledhacksaw shown

in the illustration is not adjustable, although it may be constructed with the

adjustable feature. It is also usually possible to position a hacksaw blade in any


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one of four positions, so that the operator can saw downward, upward, or to the

right or left, as desired. One such use, with the blade positioned at right angles

to the frame, is shown in Fig. 29.

FIG. 29. BLADE AT RIGHT ANGLES TO FRAME.

Hacksaw blades have holes in both ends and are mounted on the frame by

means of pins attached to the frame. The blade must always be mounted in the

frame with the teeth pointing away from the handle, and should be tightened

with enough tension to hold it rigidly between the pins.

27

Blades are made of high-grade tool steel or tungsten steel, and are available

from 6 to 16 inches in length. There are two types, the all-hardblade and the

flexibleblade. In the flexible blade, only the teeth are hardened. Thepitchof a

blade indicates the number of teeth it has per inch, pitches of 14, 18, 24 and 32

being available.

28. When selecting the best blade for a job, it is necessary to consider the type

of blade and the pitch. An all-hard blade is best for sawing brass, tool steel, cast

iron, and heavy cross-section stock. A flexible blade is usually best for sawing

hollow shapes and metals having a light cross section. A 14-pitch blade should

be used on machine steel, cold-rolled steel, or structural steel, as it will cut fastand free. The 18-pitch blade, which is the blade for general purpose work, is

used on solid stock of aluminum, bearing metal, tool steel, high-speed steel, cast

iron, etc. A 24-pitch blade is used for cutting thick-wall tubing, pipe, brass,

copper, and channel and angle iron. Use the fine tooth 32-pitch blade for

thin-wall tubing and sheet metal. Some of these uses are shown in Fig. 30.


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FIG. 30. USE THE CORRECT BLADE.

28

When selecting a blade, it is also necessary to consider the set, which means that

some teeth are pushed sideways in one direction and the same number in the

opposite direction, according to definite patterns. The set provides clearance for

the blade so that it will not jam and stick, and also prevents overheating the

blade. Since the blade has a thickness of about .025 inch, the set causes it to

make a cut about twice that wide. Three types of set are shown in Fig. 31.

Fig. 31. TYPES OF SET.

29. When preparing to use a hacksaw, secure the material in a vise, or with

clamps, if it is not already firmly anchored. It must be held firmly to prevent the

blade from chattering or twisting. Make sure that the hacksaw blade is the

correct one for the purpose and that it is in good condition. See that the teeth

point away from the handle, and check and adjust the blade tension.

It is often helpful to file a V-shaped nick at the starting point; the blade will then

start more easily. Hold the saw at an angle that will keep at least 2 teeth cuttingall the time, otherwise the blade will jump and individual teeth will be broken.

The right and wrong angles for various kinds of work are shown in Fig. 32.


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Start the cut with a light, steady, forward stroke. At the end of the stroke, relieve

the pressure and draw the blade straight back. After the first few strokes, make

each one as long as the hacksaw frame will allow, thus preventing the middle

teeth from overheating and wearing rapidly. Use just enough pressure on the

forward stroke to make each tooth remove a small amount of metal. As the

teeth point forward and the forward edges do the cutting, it is not necessary touse pressure on the back stroke.

When sawing alongside a scribed line, remember to stay just

29

FIG. 32. STARTING HACKSAW CUTS.

outside that line. Use long steady strokes, about 40 to 50 strokes per minute. If

hacksaw blades are worked too fast, the heat that is generated may draw the

temper and make the- blade soft and useless. Working too fast also may breaksome of the teeth, cramp and break the blade, or produce ragged and crooked

cuts. When near the end of the cut, slow down still more, so that the saw can be

controlled when the stock is sawed through. When finished with the saw, clean

the chips from the blade, loosen the tension, and return the hacksaw to its

proper place. A hacksaw should be hung up when not in use. It should not be

kept in a drawer with other tools or where metallic objects will strike the blade

teeth. Wiping the blade with an oily rag will prevent rusting.

When a saw blade is broken and a new blade is to be used, turn the work so that

the cut can be resumed on the other side, if possible. The reason is that the set

of the new blade is greater than that of the used saw, and the new blade would

possibly jam if work were continued at the same place. If it is necessary to use

the new blade exactly in the same cut, however, run it through the unfinished

part very carefully before attempting to complete the job.

30. Chisels.-One of the most valuable tools aboard ship is theflat cold chisel.

These chisels are usually made of octagonal

30


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tool-steel bar stock, carefully hardened and tempered, and are used for cutting

purposes where snips or a hacksaw cannot be used. They are also used to shear

off rivets, to smooth castings, to split rusted nuts from bolts, etc. As shown in

Fig. 33, the cutting edge is ground slightly convex. This causes the center portion

to receive the greatest shock, and protects the weaker corners.

FIG 33. FLAT COLD CHISEL.

Chisels must be sharp to give satisfactory service. The cutting angle should be

about 60, as shown in Fig. 33, and sharpening is best done on a wet grinding

wheel. However, if a dry wheel is used, the chisel should not be pressed too

hard against the wheel, or held there for too long a time. Too much pressure or

lengthy periods of grinding will generate sufficient heat to draw the temper outof the steel. A container of water should be kept at the grinder and the chisel

dipped in it after each light cut. This cools the metal and enables the grinding to

be continued. Remember that the chisel will not be safe to use if the cutting

angle is ground too small. On the other hand, if the angle is much over 60, the

tool will not cut properly.

31. When using a chisel for ordinary work, a hammer weighing from 1 to 1 3/4

pounds should be used. However, be sure to use a hammer that is heavy

enough for the job. When using a larger chisel, a heavier hammer must be used.

Hold the chisel in the hand with the head of the chisel close to the thumb andfirst finger, and grasp it firmly, but with the fingers rather relaxed. When the

chisel is gripped in this manner, the user will not be

31

hurt so badly if he should miss the chisel and strike his hand with the hammer.

Do not look at the head of the chisel while striking it with the hammer; watch

the cutting edge.

When cutting wire or round stock with a cold chisel, the following procedure is

recommended:

(a) Mark with a scriber or file, or with chalk or colored pencil, the point

at which the cut is to be made.

(b) Hold the work in place on the anvil or other suitable support. (It is

advisable to protect the anvil with a piece of scrap metal.)

(c) Hold the chisel as shown in Fig. 34, with the cutting edge on the

mark and the body of the chisel in a vertical position.


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FIG. 34. CUTTING ROUND STOCK WITH COLD CHISEL.

(d) Strike the chisel a light blow with the hammer, and then examinethe chisel mark on the work to make certain that the cut is at the

desired point.

(e) Drive the chisel into the work with vigorous blows. The last few

strokes, however, should be made lightly in order to avoid unnecessary

damage to the supporting surface.

(f) Heavier work can be cut in much the same way, except that the cut is

made about halfway through the stock from one side, then the work

turned over and the cut finished from the opposite side.

32. The cutting of sheet or plate metal with a cold chisel should be avoided

whenever possible, as stretching of the metal

32

invariably results. However, when no other means are available, the best

procedure is as follows:

(a) With a scriber, draw a straight line on the work where the cut is to

be made.

(b) Grip the work firmly in a vise with the scribed line even with or just

below the top of the vise jaws, as shown in Fig. 35. The waste metal

should extend above the jaws. In some cases it is better to place the

metal between two pieces of angle iron and clamp the whole set-up in

the vise. The angle iron then protects the tops of the vise jaws.

(c) Using a sharp chisel, start at the edge of the work and cut along the

scribed line, using the vise jaws (or the pieces of angle iron) as a base

for securing a shearing action. Hold the chisel firmly against the work

and strike it vigorously. Be sure to keep the cutting edge of the chisel

flat against the vise jaws.


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FIG. 35. CUTTING SHEET METAL WITH COLD CHISEL.

33. Chippingis the term applied to the method of removing metal from a surface

with a chisel, as shown in Fig. 36, which also illustrates the correct and incorrectmethods of preparing the cutting edges. When chipping steel, it is advisable to

lubricate the chisel point with light machine oil. This makes the chisel easier to

drive and helps it to cut faster than when dry. When chipping cast iron, chip

from the edges of the work toward the center to avoid breaking off corners.

34. After a chisel has been used for some time, the blows of the hammer will

cause the head to spread out until it looks like a

33

FIG. 36. CORRECT AND INCORRECT SHARPENING.

ragged mushroom. The spread-out head is rough, and will cut the hand very

easily. In some cases, pieces of the jagged edge may break away and fly off with

sufficient force to injure someone working nearby. The head of the chisel must

therefore be periodically ground back to its original shape, as shown in B, Fig.

37.


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FIG. 37. KEEP CHISEL HEAD GROUND OFF.

Always wear goggles when chipping with a chisel. Also be careful not to send

chips flying toward other workmen or into machinery. The safest method is to

have a guard (a piece of canvas of sufficient size attached to two woodenpedestals) placed so as to catch the flying chips. Keep the hammer and the head

end of the chisel clean and free of grease and oil to prevent the hammer from

slipping.

35. Special Cold Chisels.-If it is necessary to cut keyways or slots, the cape chisel

can be used. This chisel is like a flat chisel except

34

that the cutting edge is very narrow. It has the same point angle, and is held and

used in the same manner.

Rounded or semi-circular grooves should be cut with the round-nose chisel. This

chisel is also used to "draw back" a drill that has "walked away" from its

intended center.

The diamond-point chiselis tapered square at the cutting end, then ground at an

angle to provide the sharp diamond point. It is used for cutting V-grooves and

inside sharp angles. These chisels are shown in Fig. 38.

FIG. 38. SPECIAL CHISELS.

36. Files.-Files are hardened steel tools for cutting, smoothing, or polishing

metal. They vary in length, in shape, and in arrangement, or cut, of teeth, so as

to provide files for various uses. The terms commonly used to describe a file are

given in Fig. 39.


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FIG. 39. FILE TERMINOLOGY.

37. Files have either single-cutor double-cutteeth. The difference between the

two types of teeth is apparent when comparing Figs. 40 and 41. Single-cut files

have rows of teeth cut parallel to each other, the teeth being set at an angle of

about 65 with the centerline. Single-cut files are used for sharpening. tools,

finish filing, and draw-filing. They are also the best tools for smoothing the

edges of sheet metal.

35

FIG. 40. SINGLE-CUT FILE.

FIG. 41. DOUBLE-CUT FILE.

Double-cut files have criss-crossed rows of teeth, the double cut forming teeth

that are diamond-shaped and suitable for quick removal of metal and for rough

work.

38. In selecting a file for a job, it is necessary to consider its shape, which means

both the outline and the cross-sectional shape. Some of the cross-sectional

shapes of files are shown in Fig. 42.

FIG. 42. SHAPES OF FILES.

Mill filesare tapered both in width and thickness, and are available with either

square or round edges, or with one safe edge, that is, an edge with no teeth. Mill

files are used for lathe work, draw-filing, and other fine, precision work. They are

always single-cut.

Flat filesare general purpose files, tapering in width and thickness, and generally

used when a fast cutting tool is desired. Hand files, not shown, are somewhat

thicker than flat files, but their edges are parallel.

Square filesare tapered on all four sides and are used to enlarge rectangular-shaped holes and slots. Round filesserve the same purpose for round openings.

Small round files are often called rat-tail files.


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The half-round fileis a general purpose tool, the rounded side being used on

curved surfaces and the flat face on flat surfaces. When filing an inside curve, a

round or half-round file with a

36

curve most nearly matching the curve of the work should be used.

Triangular, or 3-squareor 3-corner files, are tapered on all three sides. They are

used to file cutters, acute internal angles, and to clear out square corners.

Special triangular files are used to file saw teeth.

A warding file, not shown, is extremely thin and has sharply tapered edges. Its

chief use is on work where space is limited. Knife fileshave one thin edge and

one thick edge, and are used on keyways, slots, etc. A raspis similar to the file

except that it has coarse teeth raised by a triangular punch, and is usually used

on wood.

39. Files are also graded according to the spacing and size of their teeth, or their

coarsenessandfineness. These grades are known as rough-cut, middle-cut,

bastard, second-cut, smoothand dead-smooth. Three grades of teeth are shown in

Fig. 43. The fineness or

FIG. 43. GRADES OF FILE TEETH.

coarseness of file teeth is also influenced by the length of the file. If the teeth of

a 6-inch, single-cut smooth file, for example, are compared with those of a

12-inch, single-cut smooth file, the difference will be noted.

40. The type of material to be filed, and whether it is a rough or finishing cut,

determine the grade of fineness that is required. Various typical situations may

be listed as follows:

37

(a) For heavy, rough cutting, a large, coarse, double-cut file is best.

(b) For the finishing cut, use a second-cut or a smooth single-cut file.

(c) When filing cast iron, start with a bastard file and finish with a


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second-cut.

(d) When filing soft steel, start with a second-cut file and finish with a

smooth file.

(e) When filing hard steel, start with a smooth file and finish with a

dead-smooth file.

(f) When filing brass or bronze, start with a bastard file and finish with a

second-cut or smooth file.

(g) When filing aluminum, lead, or babbitt metal, use a bastard file, or if

available, afloat-cut filemay be used. This file has large curved teeth

and works with a planing action. It is fitted with a special holder, as

shown in Fig. 44, and is sometimes known as a vixen-cut file.

FIG. 44. FLOAT-CUT FILE.

41. Never use a file unless it is equipped with a tight-fitting handle. If a file is

used without the handle and it strikes something accidentally or jams to a

sudden stop, the tang may be driven into the hand.

File handles are made of wood with a ferrule, or metal strengthening ring, on

the end, and a hole to receive the tang of the file. The usual way of driving the

handle on the file is to insert the end of the tang into the hole in the handle, and

then tap the end of the handle on the bench or some other flat surface. If the

tang of the file is considerably larger than the hole in the handle, the hole may

be enlarged by burning it out with the heated tang of a file. A piece of wet rag or

waste should be wrapped about the file up to the tang before the file is heated,to prevent its temper from being drawn.

The correct way to hold a file is with the handle against the palm

38

FIG. 45. CORRECT WAY TO HOLD FILE.

of the right hand, thumb on top, as shown in Fig. 45. Hold the end of the file in

the left hand with the fingers curled under it. When filing, lean the body forward

during part of the forward stroke and straighten up at the finish. The file mustbe held straight or the surface of the work will not be flat. Not more than 30 or

40 strokes per minute should be taken; too much speed will cause the file to


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rock, and the corners of the stock will be rounded off, as indicated in view A of

Fig. 46. Too much pressure will bend the file and tend to have the effect shown

in view B.

FIG. 46. TOO MUCH SPEED AND TOO MUCH PRESSURE.

Apply pressure on the forward stroke only. Unless the file is lifted from the work

on the return stroke, it will become dull much sooner than it should. (This does

not apply, however, when filing very soft metals, such as lead or aluminum. On

soft work, pressure on the return stroke helps to keep the cuts in the file free of

removed metal.)

42. When round surfaces are filed, best results are obtained by working as

shown in Fig. 47, a rocking motion being used.

Surfaces and edges are often draw-filedto make them smooth and true. Indraw-filing, hold the file at right angles to the work,

39

FIG. 47. FILING ROUND SURFACES.


34/72

FIG. 48. DRAW-FILING.

as shown in Fig. 48, and move the file sidewise along the work. A single-cutsmooth file should be used. Pressure is heaviest on the stroke made toward the

body and very light on the return. Keep the hands as close together as possible

to prevent bending the file, and watch the ends and corners of the work, as they

are easily rounded. For a smoother surface than can be obtained by draw-filing,

wrap a piece of fine emery cloth around the file and proceed as in draw-filing.

When filing work that is rotating in a lathe, long, slow cuts give best results. The

work must be rotating at high speed. For rough work, a double-cut flat file is

generally used. For finishing work, a mill file gives better results, as it is a

single-cut file and has a shearing action. Too much filing of a piece of work in a

lathe, however, will, as a rule, spoil it by making it out of round.

40

43. A new file should be broken in by using it first on brass, bronze, or smooth

cast iron. Most of the damage to new files is caused by using too much pressure

during the first few strokes, so it is necessary to use a light pressure to prevent

tooth breakage. A new file should not be broken in on a narrow surface, such asthe edge of sheet metal, because the narrow edge is likely to break off the sharp

points of the teeth. A new file should never be used to remove the scale on cast

iron; always use old, worn files for removing such scale. A file should never be

used on material harder than itself.

During the operation of filing, small particles of the work are likely to clog the

teeth of the file and scratch the material being filed. This condition is known as

pinning. Pinning is sometimes the result of putting too much pressure on the

file, especially if it is a new one. To avoid pinning, therefore, be sure that the file

is broken in properly. Rubbing chalk on a file before using it will also help to

prevent pinning.

Pinning can also be prevented by cleaning the file frequently. This is done by

means of afile card, an example of which is shown in Fig. 49. When cleaning a

file, lay it flat on the bench and draw


35/72

FIG. 49. FILE CARD.

the bristles of the file card back and forth across the file parallel to the cuts. If a

few chips are stubborn and will not come out, remove them with the pick that is

included with the file card.

To prevent scratching or cutting too deep when filing wrought iron, steel, or

hard fiber, apply a little oil to the surface of the file.

41

However, do not use oil when filing cast iron, as it causes the cast iron surface to

glaze over and become hard and slick.

44. A file is easily dulled by rough or improper handling, and files therefore

should not be stored in a drawer or box where they can rub against each other

or against other tools. It is best to store them, in separate holders, or in holes

cut in a wooden block. Do not use a file for prying or pounding. The tang is soft

and bends easily, the body is hard and extremely brittle, and even a slight bend

may cause a file to snap in two. Bending or pounding a file, therefore, will notonly injure the file but may cause steel particles to be thrown into the eyes. For

similar reasons a small rat-tail file should not be salvaged to be used as a prick

punch or center punch.

45. Drills and Drilling.-There are many occasions when it is necessary to drill

holes in metal, using a twist drill, a tool that does its work by slicing metal away

as it rotates. With holes up to 1/4 inch in diameter, the drilling may be done by

hand, using a hand drillor breast drillto hold and turn the drills. A braceis

ordinarily used when drilling holes in wood. These hand drilling tools are shown

in Fig. 50.

Twist drills are also used for cutting larger holes in metal, up to 4 inches in

diameter, but for such purposes are usually operated by power drilling

equipment.


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FIG. 50. HAND DRILLING TOOLS.

42

Twist drills are made of carbon steel or high-speed alloy steel. Carbon steel drills

are satisfactory for the general run of work and are less expensive, although

they may lose their hardness if heated excessively. High-speed drills are used on

tough metals and at high speeds. They will keep on cutting when red hot, but

should be cooled in still air; if cooled quickly they may crack or split.

The drill shankis the end that fits into the chuck of the hand drill, electric drill or

drill press. Straight-shank drills are used to drill holes up to about 1/2 inch in

diameter. Larger holes are usually drilled with the taper-shank drill. The

square-shank drill is made to use in a brace. The different shanks are shown in

Fig. 51.

FIG. 51. TWIST DRILL SHANKS.

Twist drills are available with either 2, 3, or 4 flutes (the spiral grooves formed

along the sides), but drills having 3 or 4 flutes are used for following smaller


37/72

drills or for enlarging cored holes, and are not suitable for drilling into solid

stock. The spiral flutes provide several advantages:

(a) They give a correct rake angle to the lips, as shown in Fig. 52.

(b) They cause chips formed while drilling to curl tightly so that they

occupy the minimum amount of space.

43

(c) They form channels through which such chips can escape from the

hole.

(d) They allow the lubricant, when one is used, to flow easily down to

the cutting edge of the drill.

FIG. 52. RAKE ANGLE.

46. Drill Sizes.-The twist drills used most frequently are those made in fractional

sizes, from 1/64 inch up to 1 inch in diameter, although larger sizes are also

found aboard ship. The size of the drill is stamped on the shank. Because the

drills vary 1/64 (0.0156) inch from one size to the next, two other identification

systems have been developed for special sizes:

(a) Number drills, ranging from No. 80 (0.0135 in.) to No. 1 (0.228 in.).

(b) Letter drills, ranging from A (0.234 in.) to Z (0.413 in.).

Tables of drill sizes will be found in Marine Engineering Tables, issued later in the

course.

If the size number has worn off the drill shank, the size can be checked with a

drill gage, Fig. 53, for the number drills, with a drill standfor fractional drills, or

with a micrometerfor any kind of drill. When measuring a drill with a

micrometer, measure from

FIG. 53. DRILL GAGE.

44


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FIG. 54. TWIST DRILL TERMINOLOGY.

It runs the entire length of the drill between the flutes, gradually increasing in

thickness toward the shank.

49. Drill Lips.-It has been determined that for work on mild steel and for

general purpose work, the lips of a twist drill should be ground to a 59 angle, or

with an included angle of 118, as shown in Fig. 56. In this illustration the angle

is measured by a drill gage. (Note that both lips are exactly the same length.) If

the angle is too great, the point will be too flat to center properly; if the angle is

too small, the hole will be drilled less rapidly than it should be, and more power

will be required to drive the drill. If the point is on center but the cutting edges

are ground at different angles,

46


40/72

Fig. 55. DRILL WEB.

the drill will bind on one side, as shown in the left-hand view of Fig. 57, and as

only one lip will do the work, that edge will wear rapidly. When the cutting edges

are not the same length, the hole will be larger than the drill, as shown in the

center view.

50. Lip Clearance Angle.-For most drilling, the heel of the drill should be

ground away from the cutting lips at an angle of from 12 to 15 at the

circumference of the drill, as shown in the right-hand view, Fig. 57. This angle isknown as the lip clearance angle. Examples of incorrect lip clearance grinding

are shown in Fig. 58.

The drill at the left, Fig. 58, has been ground without any lip clearance whatever;

in the center example, the lip clearance angle is so large that the cutting edges

of the drill have broken down because of insufficient support; in the illustration

on the right, the lip clearance angle is too small.

47


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52. Recommended Angles for Various Materials.-The following tabulation

states the lip angles and lip clearance angles that are recommended for

common materials:

Materials to be drilled Drill Angles

Heat-treated steels, drop forgings,

Brinel hardness No. 250.

125 included angle

12 lip clearance

Cast iron, soft90 included angle

12 lip clearance

Brass

118 included angle

12 lip clearance

Slightly flat face of cutting lips

Copper100 included angle

12 lip clearance

Wood60 included angle

12 lip clearance

53. Grinding a Drill.-After the instructions have been studied carefully,

considerable practice is still needed in order to learn how to grind a drill

correctly. To secure this practical experience, it is advisable to begin by selecting

a correctly ground drill; a 1/4-inch or 3/8-inch size would be suitable for the

purpose. Take the drill to the grinder, and without turning on the grinder,

observe just how the drill must be held in order to secure the correct shape of

the point and the desired angles. The way in which the drill is held against the

grinding wheel is shown in Fig. 59.

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FIG. 59. GRINDING A DRILL.

Next take a drill that needs grinding badly, and start up the grinder and try to

shape the point of the old drill to be exactly like the correctly ground drill.

Remove very little metal at first and examine the drill frequently in order to note

the progress made. Also take the same precautions that are explained in Art. 30

in connection with the sharpening of chisels. By working and observing carefullyit will soon become apparent how the drill must be held in order to secure the

desired results. Check the lip angle and lip clearance angle, and when the drill


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appears to be ground properly, try drilling a hole in a piece of soft steel scrap.

Note whether the drill cuts smoothly and rapidly, or whether it jumps and

chatters. Do the chips curl away evenly from both lips? Is the hole the right size?

Examine the heel of the drill; if there are shiny spots, it is indicated that the lip

clearance angle is too small. If the drill will not cut at all, it is probably because

there is no lip clearance. Be careful to keep both lips the same length, and have

the included angle as previously recommended.

Always protect drills from nicks and rust. See that they are ground properly

before putting them away, and then store them carefully.

54. Drilling.-When drilling with a twist drill, the following procedure is

recommended:

(a) Locate the exact position of the hole by drawing two lines

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on the work at right angles, the lines crossing each other at the point which is to

be the center of the hole. Make a light mark with a prick punch where the lines

intersect, and check to make sure that the prick punch mark is located exactly

where they cross. Then use a center punch to sink the mark deep enough to

receive the point of the drill. Select a sharp, properly ground drill of the desired

size; insert the shank in the chuck and fasten it tightly in position. Grip the work

firmly in a vise unless it is stationary. Arrange to do the drilling horizontally, if

possible. Put a drop of lubricant, if needed, in the impression made by the

center punch. Place the point of the drill in the center punch impression and

begin drilling, making sure to keep the drill at right angles to the surface of the

work. Keep a steady, firm pressure on the drill.

(b) When the drill has started to cut and has made an impression larger than the

center punch mark, lift it from the work and note whether the impression is

concentric with the cross lines. If it is not concentric, as shown in the left-hand

view, Fig. 60, use a round-nose chisel to make a nick in the impression on theside of the center toward which the drill should be drawn. The chisel cut is

shown in the center view, Fig. 60.

FIG. 60. HOW TO DRILL BACK TO CORRECT CENTER.

(c) Put another drop of lubricant in the impression and continue drilling until the

point of the drill just breaks through the metal. Then ease off on the pressure

and drill slowly until the hole is completed. If the drill catches while finishing the

hole, work the drill back and forth carefully until it cuts through the work. When

the hole is completed, withdraw the drill immediately by pulling it back as it

continues to turn.

55. Portable Power Drills.-A portable electric drill is used in much the same


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way as a hand drill. The chuck shaft, or arbor, is

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geared to the motor to obtain the desired speed. Small drills are geared up for

high speed, but the larger drills are geared down so that the chuck will turn

slowly enough to prevent damage to the drill from burning. Portable power

drills can also be used for such operations as buffing, polishing, and grinding.

With the addition of a special attachment which converts the rotary motion of

the drill into a reciprocating motion, a portable power drill can be used for

making holes in concrete and similar materials. The same attachment can also

be employed to adapt the machine for lighting riveting work.

Except for the smallest units, the extension cable of portable electric drills

should include a ground lead from the drill casing, and a clip for connection of

the ground lead toground. The clip should be fastened to a grounded

conductor, such as the conduit at the outlet box, before the drill is placed in

operation. This precaution protects the operator of the drill from electrical shock

in case the insulation of the wiring within the power drill casing should fail,

resulting in a short circuit.

Portable electric drills are susceptible to short circuits because of their small

clearances and the metallic dust produced when they are used. These

conditions can be improved by periodically blowing through the motors withclean dry air. Since dampness is another reason that may cause the machines to

deteriorate, they should always be stored in a dry place when not in actual use.

It is also advisable that they be regularly tested for insulation resistance.

Before a portable power drill is used, the extension cable should be inspected

carefully to -make sure that it is not frayed or crimped to such an extent that

wiring is exposed. Care should also be taken that the cable does not drop or lie

in water. The operator of the drill should wear leather gloves and keep his

footgear dry, especially where dampness may be present.

56. Drill Press.-A small drill press, such as might be used aboard ship, is shown

in Fig. 61. This drill press has a separate motor which drives the drill spindle and

chuck by means of a V-belt.

One advantage of the drill press over the portable electric drill is that speed

control is provided. Four steps are usually found on the motor pulley and four

on the spindle pulley. The drill press in the illustration is arranged for high

speed, with the belt on the largest step of the motor pulley.

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FIG. 61. DRILL PRESS.

The feed pressure is easily controlled on this drill press by means of a feed

wheel with long handles. A depth stop is provided to stop the progress of a drill

at a predetermined depth, which is important when drilling holes that do not go

all of the way through the material.

When using a drill press, it is very important to hold the drilled material securely.Never try to hold it down by means of the hands, as the drill may catch or jam

and spin the material around at high speed, endangering everyone within range.

The best method is to use a drill vise or some other form of clamping device. A

drill vise, also a V-block and clamp used to hold round objects, are shown in Fig.

62. Use the drill vise for small jobs, and clamp larger pieces of stock to the drill

table.

It is usually advisable to protect the drill table by placing a block of wood

beneath the work, thus preventing the drill from touching and scarring the drill

table as it completes the drilling of a hole.

57. Heavy-duty Ratchet Drill.-When the hole to be drilled is too large for an

electric drill, and the piece to be drilled cannot be taken to a drill press, a

heavy-duty ratchet drill can be used. In order to use the drill, some arrangement

must be made to apply

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FIG. 62. DRILL VISE AND V-BLOCK.

1. ratchet sleeve

2. base

3. upright

4. adjustable arm

5. bolt

6. steel plate

7. bolt

8. drill

9. ratchet handle

10. ratchet

11. clamp

FIG. 63. RATCHET DRILL AND "OLD MAN."

54

pressure upon it. The arrangement may utilize blocking, depending upon the

nature and position of the work, or a device known as an "old man" may be

used. A ratchet drill set up in an "old man" is shown in Fig. 63.

As shown in the illustration, the base of the device is bolted or clamped in

position, and the adjustable arm is placed at the proper height so that the


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pointed tip of the ratchet fits into one of the countersunk holes in the lower face

of the arm. The position of the arm is then adjusted so that the drill is lined up

properly, and the arm is bolted securely on the upright. By turning the ratchet

sleeve so as to screw it upward, the drill is held securely between the arm and

the work, and drilling can be begun. The drill is turned by pulling on the ratchet

handle. In order to feed the drill into the work, a rod is placed in one of the small

holes at the upper end of the ratchet sleeve, and by means of this leverage the

ratchet sleeve can be held from turning during part of the stroke of the ratchet

handle, thus lengthening the drill assembly and feeding the drill through the

work. The amount of feed given is determined by the nature of the work being

done, and can be judged by the amount of pull needed to move the ratchet

handle.

58. Pilot Holes.-A small hole, used to guide and mark the path for a larger drill,

is known as apilot hole. It is a good policy to drill these small guide holes for any

drill size larger than 3/16-inch, as it is difficult to start a large drill in a centerpunch mark, the large drill having a tendency to drift from the center. The pilot

hole guides the larger drill all the way through the metal and helps to keep it "on

the course." No special drills are required, just select the pilot drill according to

the size of the finished hole that is to be made, a 1/8-inch drill, for example,

being satisfactory for drilling a pilot hole for a 3/8-inch drill.

59. Keep a drill cutting all the time it is in contact with the metal. Apply pressure

steadily and uniformly to insure continuous cutting. Remember that both too

much pressure and too little pressure can cause overheating of the drill.

After a hole has been drilled, the burrsmust be removed. An easy way to

remove them is to use a drill about twice the diameter of the hole. Hold the drill

in the hand and rotate the point against the burrs. Do not burr a hole too much,

however, as the hole should

55

be a true cylinder and should not be countersunk at either end unless sospecified.

60. Countersinks.-A countersink is used to shape the ends of drilled holes to fit

screw, bolt, and rivet heads of the countersunk type. The 3-flute 82 countersink

is usually used, although other point angles are available for special purposes.

Countersinks are made in a number of sizes, but any one size can be used on

several different sizes of hole.

61. Counterbores.-A counterbore is used to cut recesses in metal surfaces for

fillister-head bolts and screws, and for similar purposes, working best whenused in a drill press or lathe. The pilot end of the tool is smooth, and is guided

by the hole drilled for the bolt or screw. A countersink and a counterbore are

shown in Fig. 64.

62. Solder.-Solder is used to join pieces of metal, to make metal joints and

seams leakproof, and to connect electric wires so that they will be good

conductors.

Soft solderis used most often in sheet metal and electrical work, and is usually a

combination of 50 per cent tin and 50 per cent lead, known as half-and-halfsolder. Solder is manufactured in both bar and wire forms, some wire solders

having hollow centers which are filled with acid or rosin corefluxes.


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Half-and-half solder begins to melt at a temperature of 358F, and becomes a

liquid at 415F. It does not have much strength, and should never be used

where heavy stresses will be applied to the soldered parts. Solders containing 55

per cent to 70 per cent tin are stronger and can withstand heavier stresses than

half-and-half solder, but no soft solder approaches the strength of the hard

solders.

Hard soldersare made of alloys of copper, zinc, silver, and tin. They will

withstand considerable stress, pressure and vibration, and may be used to

solder high-pressure pipe connections, gasoline and oil piping joints, etc. The

hard solders must be melted with a blowtorch or welding torch; soldering irons

do not conduct enough heat to melt them.

63. Soldering Irons.-Soldering irons, or coppers, are available in various

weights, but the size used should depend on the

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FIG. 64. COUNTERSINK AND COUNTERBORE.

requirements of the work to be done. As a general rule it is best to select the

largest size that is convenient to handle. The points of soldering irons should be

rather blunt for efficient heat conduction, three different shapes being shown in

Fig. 65. Thepointedshape is used for utility work; the stubshape is used for flatseams that require considerable heat; and the bottomtype is best for soldering

the seams of pans, trays, etc. An electric soldering iron, with interchangeable


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tips, can be used for light work and is especially good for work on electrical

connections.

64. Blowtorch.-Soldering irons can be heated in various ways, but the gasoline

blowtorch is one of the most convenient means aboard ship. As shown in Fig.

66, blowtorches are usually equipped with

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FIG. 65. SOLDERING IRON POINTS.

a hook and curved rest to hold the soldering iron while the point is exposed tothe flame of the torch.

Before using a blowtorch it is advisable to consider the danger of fire. Do not

light or use the torch near openings where explosive gases may be present,

where gasoline has been spilled, or where inflammable material may be ignited.

It is good practice to have a fire extinguisher handy whenever a blowtorch is

used.

1. soldering-iron rest

2. soldering-iron hook

3. valve

4. fuel pump

5. fuel pan

6. burner tube


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FIG. 66. BLOWTORCH.

58

In order to use a blowtorch, the tank must contain clean, white (unleaded)

gasoline, and the pump on the tank must be operated to build up sufficient

pressure to cause the gasoline to spray through the burner tube when the valve

is opened. A piece of sheet metal or other convenient means is then used to

shield the end of the burner tube and the valve is opened slightly, allowing liquid

gasoline to collect in the fuel pan. With the valve closed and the blowtorch

placed so that it is clear of inflammable material and is not subjected to violent

air currents, ignite the gasoline in the fuel pan and permit the flame from the

burning gasoline to envelop and heat the burner tube. When the burner tube ishot, open the valve slightly, so as to permit a fine stream of gasoline to be

discharged from the tank. The gasoline should vaporize immediately and burn

with an almost colorless, light-blue flame. Be sure to open the valve wide

enough to permit satisfactory operation. When the torch is burning

satisfactorily, the valve can be opened or closed slightly in order to adjust the

flame to the desired intensity. A blue flame indicates good combustion

conditions. While the torch is in use it is necessary to work the pump a few

strokes periodically in order to maintain pressure in the tank.

To extinguish a blowtorch, close the valve. After the torch has beenextinguished, it is good practice to loosen the filling plug and relieve the

pressure within the tank. When the pressure has been relieved, the filling plug is

tightened again. The valve is then opened slightly and left open. If the valve is

not left open, the metal around the valve will contract and the valve may stick so

tight that it will be damaged.

65. Fluxes.-A flux is a chemical preparation (powder, paste, or liquid) used to

keep the metal clean so that the solder will stick to it. If a flux is not used, the

heat will cause oxides to form on the metal surface and prevent the solder fromadhering firmly. A list of common fluxes and the metals on which they are used

is given in the following:


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Metals Fluxes

Brass, copper, tin Rosin

Lead Tallow, rosin

Iron, steel Borax, sal-ammoniac

Galvanized iron, zinc Zinc chloride

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Fluxes are either corrosive or non-corrosive. The commonly used corrosive

fluxes; zinc chloride and sal-ammoniac, corrode the metal if allowed to remain

on it after soldering. They should therefore be completely removed by a

thorough washing after the work is done. 'It is for this reason that rosin, a

non-corrosive flux, is used when soldering electrical connections. The rosin is

used in powdered form, or as a liquid core in wire solder.

Zinc chloride can be prepared by dissolving small pieces of zinc in commercial

hydrochloric acid, commonly known as muriatic acid. The zinc should be added

a little at a time until the bubbles stop rising, and a little undissolved zinc

remains in the solution. It is important to note that the gas released when these

bubbles reach the surface is hydrogen, which is highly explosive. It is therefore

advisable to practice the same precautions as with storage batteries, that is,

keep the room well ventilated and avoid the use of open flames.

The solution should be strained and then diluted to the correct strength by

pouring it into an equal amount of water. (Always pour the acid into the water; it

is dangerous to pour water into acid.) The resultant liquid is zinc chloride, also

known as "cut-acid" or "killed acid." It is recommended that a few small pieces of

zinc be placed in the liquid in order to neutralize any free acid that may remain.

As acid fluxes eat away metal, they must be stored in pottery or glass

containers.

Paste fluxes, commercially manufactured, are available in cans of various sizes.

These fluxes, which contain grease for counteracting corrosion, are substitutesfor acid fluxes.

66. Tinning.-Tinning means to spread a thin layer of solder on the surfaces of

the metals that are to be soldered together, causing the solder to adhere to the

metal and make a firm union with it. The purpose of tinning is to prepare the

surfaces so that they will unite readily in the process of soldering and make a

firm joint. It is recommended that all metals, except lead and tin, be tinned

before soldering. Lead and tin need only to be scraped clean.

Copper, brass and ungalvanized iron may be prepared to receive solder bycleaning the surfaces and applying zinc chloride. Galvanized iron or sheet zinc

should be cleaned with muriatic acid before the solder is applied. Where a metal

has become tarnished, it is necessary to remove the tarnish and expose the

bare, clean

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metal before tinning it; otherwise the solder ordinarily will not adhere to the

metal.

67. Tinning the Soldering Iron.-The point of a soldering iron must be tinned


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before it will do a good job of soldering, tinning in this instance referring to the

process of coating the point with solder to prevent oxidation when heated. The

general steps in the tinning procedure are as follows:

1. File the faces of the point (or ru

Engine Room Tools Part 1

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