this plan is followed, it is common practice to include, in addition
to a stock of clamps and bolts of various sizes and lengths, pack-
ing blocks for the clamps. In some plants, a standard wrench is
sent out with each set of bolts, clamps and blocks, so that the
time for setting up a machine is reduced as far as possible. When
bolts are returned to the supply room, each one should be ex-
amined to see that the nuts can be turned freely by hand.
Storage of Blueprints. Tool store-rooms are not only used
for equipment of the general classes mentioned, but in many
cases for keeping blueprints as well, especially in plants where
duplicate machines are constantly being built. When blue-
prints are kept in this way they are usually given out in exchange
for a check the same as a tool. A duplicate set of prints may be
filed in the office of the machine shop foreman or superintendent
for reference purposes only. These office prints should prefer-
ably be bound or filed together in sets, so that the foreman always
has a complete set for his own use, instead of being obliged to
refer to those which are scattered about the shop.
One method of handling blueprints which has proved satis-
factory is to mount them on thin steel plates, heavy cardboard,
or wood. A thin material is preferable, owing to the relatively
STORAGE AND MAINTENANCE OF TOOLS 151
small space required for storage. Blueprints mounted in this
way are protected while in the shop and they can be easily filed
for future use.
In a great many machine shops, blueprints are destroyed when
they are no longer needed in the shop for a certain job. The
reason for destroying them instead of filing them away for future
use is that, in many cases, the blueprints are either soiled or torn
to such an extent that it is preferable to make new ones when they
are needed again. Naturally the extent to which blueprints are
soiled varies with the length of time they are kept in the shop,
and may depend considerably upon the kind of work done, so
that the practice of destroying them might not always be justified.
Storage Fixtures for Tools. The fixtures, such as racks,
shelves, bins, and drawers in which various kinds of tools are
stored, should, as far as possible, be compactly arranged, in order
to economize in space. The light should also be distributed
evenly so that there are no dark shelves or bins, and it is impor-
tant to arrange each fixture in such a way that the tools may be
removed without difficulty. Each tool or tool set should have a
definite place in the tool cabinet and provision be made for iden-
tifying and locating different classes of tools. A common method
of marking different sections of a tool supply room is by means of
letters and numbers, the letters indicating main sections and the
numbers showing the location of racks, bins, drawers, or other
storage places in each section.
General Arrangement of Storage Fixtures. When designing
storage fixtures of any kind, it is advisable not to conceal the
tools any more than is necessary, although drawers or trays are
often considered preferable for small drills, taps, reamers and
other tools that might be lost or misplaced if kept in open bins
or shelves. Shelves or box-shaped enclosures should be large
enough to permit the hand to be inserted without interference.
Trays or open shelves for small tools should have shallow or low
partition strips for separating different sizes of tools, and if such
receptacles slope toward the front the tools may be seen better
and. more easily removed. Edged tools, such as reamers and
milling cutters, should be separated so that they will not strike
10 B
152
SHOP MANAGEMENT
against each other. Reamers, taps, etc., are sometimes held
vertically by inserting the shanks in holes made in a special rack;
such tools are also kept in trays or drawers having low partition
strips to prevent direct contact between different tools. Fig. i
shows reamer and drill cabinets in a tool supply room of the
Cadillac Motor Car Co. The reamers are placed in separate
Fig. i. Drill and Reamer Cabinets
pockets formed in crosswise strips so that they do not roll against
each other and thus injure the cutting edges (see the three
drawers to the left which have been removed).
The height of tool racks and cabinets usually varies from five
or six feet to the height of the tool supply room ceiling. Low
racks (Fig. 2) are usually found in shops having plenty of space.
A ladder supported by a track and rollers is convenient for high
STORAGE AND MAINTENANCE OF TOOLS
racks such as are found in many city shops, located where land
and space have a relatively high value. (See Fig. n.) Wood
is generally used for tool racks and cabinets in tool supply rooms,
although many of the new plants have steel shelving.
Unit System of Cabinet Construction. Most tool store-rooms
have cabinets or fixtures which are of permanent construction.
Fig. 2. Collet Rack
It is desirable, however, to so construct the storage equipment
that it can be rearranged and expanded to accommodate a larger
stock of tools, if this should be necessary on account of the growth
Dimensions of Standard Boxes and Trays 1
Number of Box
Outside Dimensions,
Inches
Number of Box
Outside Dimensions,
Inches
I
24 by 24
9
12 by 4
2
24 by 12
10
8 by 8
3
24 by 8
ii
8 by 6
4
24 by 6
12
8 by 4
5
24 by 4
13
6 by 6
6
12 by 12
14
6 by 4
7
12 by 8
15
4 by 4
8
12 by 6
1 The length or depth is 17 inches or less in all cases.
154
SHOP MANAGEMENT
of a plant. This unit system of construction, as applied to the
tool supply room of the Tabor Mfg. Co., Philadelphia, Pa., is
illustrated in Fig. 3. The tool cabinets consist of a main rack
having square sections which may be subdivided for storing
different types of tools by means of boxes, trays, and drawers of
Machinery
Fig. 3. Diagram illustrating Unit System of Construction for Tool Racks
standard size. The sections or compartments of the main rack
are 24! inches square and 17 inches deep. These racks are made
of wood and are rigidly constructed, as they sustain heavy loads
when filled with tools. The boxes which are inserted in these
square compartments for holding the tools are made in fifteen
standard sizes, as given in the table on the preceding page.
STORAGE AND MAINTENANCE OF TOOLS
155
Fig. 3 shows some of the combinations that are possible with
this construction; thus, section A is fitted with sixteen square
sections or boxes; section B has eight rectangular boxes; sec-
Fig. 4. Rack for Clamping Bolts of Various Lengths
tion C, four square boxes; and so on. The compartments are
fitted with whatever combination of boxes is best adapted to the
size and number of tools they are to contain. When drawers
can be used to better advantage than open boxes for the storage
156
SHOP MANAGEMENT
of small tools, cutters, etc., these drawers are inserted in double
vertical rows which fit into the standard compartments.
Racks for Clamping Bolts and Packing Blocks. Fig. 4 shows
the form of storage racks used by the Tabor Mfg. Co. for clamp-
ing bolts such as are often required for holding castings or forg-
ings on the work-tables of machine tools. The bolts are sus-
pended from T-slots formed in the standard storage boxes used
at this plant. The symbol for each size of bolt and the hooks
for the workmen's checks are placed adjacent to the various corn-
Fig. 5. View in Tool Supply Room showing Revolvable Racks for
Milling Cutters
partments. Standardizing equipment of this kind is of especial
importance in shops doing general work for which special fixtures
have not been constructed.
Cabinets and Racks for Milling Cutters. Many tool supply
rooms have cabinets of the general type shown near the delivery
window in Fig. 5 for storing milling cutters. These particular
cabinets are of octagonal form and each of the eight sides is
covered with cutters suspended on pegs. As the cabinet can be
revolved about a vertical axis, any side may be easily reached.
STORAGE AND MAINTENANCE OF TOOLS
157
The swinging or folding door type of cutter rack illustrated in
Fig. 6 is now used quite extensively. These swinging doors are
hinged to a vertical shaft and each door provides two sides for
the storage of cutters. Another compact design is similar in
construction to the familiar sliding barn door. Each door of the
Fig. 6. Swinging-leaf Type of Milling Cutter Rack
cabinet has wheels above and below it which engage horizontal
tracks for guiding the doors as they are rolled in or out. There
are several parallel doors arranged in a group with a space of
about twelve inches between them. The cutters are suspended
upon pegs pr hooks. Fig. 7 shows milling cutters stored on
158
SHOP MANAGEMENT
shelving. Different types are grouped together, and these groups
are plainly marked. Instead of placing the cutters loosely on the
shelves, they are provided with removable holders consisting of
base blocks and vertical pegs which pass through the cutter-arbor
holes.
Racks for Taps and Dies. The rack for taps shown in Fig. 8
is so arranged that the taps are held in position by their shanks,
which are inserted in holes of suitable size. This form of rack
(which is used by the Cleveland Automatic Machine Co.) pre-
Fig. 7. (Upper Section) Method of Storing Milling Cutters on
Shelves by Means of Special Holders
vents taps from being nicked or otherwise injured by striking
against one another. Each tap has a label indicating its size,
and there is also a hook for receiving the workman's check when
the tap is in use. A rack for spring screw- threading dies is shown
at the left of Fig. 8. The hollow shanks of the dies fit over pegs
on the rack which hold them in position.
Racks for Snap Gages. A good type of rack for snap gages
is shown in Fig. 9 (see upper part of cabinet). Metal partitions
are used to separate different gages, the height of these partitions
STORAGE AND MAINTENANCE OF TOOLS
and the space between them being varied in accordance with
different gage sizes. These partitions extend across the shelf at
the bottom, but curve backward toward the top, so that the upper
ends of the gages project far enough to be easily gripped for re-
moving them from the cabinet. This form of rack is found in
the tool supply rooms of the Cadillac Motor Car Co. Inciden-
tally, this illustration shows how steel partitions can be used to
form compact bins or compartments of the general type shown
just below the gage rack. The consecutive numbers of the bins
Fig. 8. Racks for Taps and Snap Gages
are stamped on circular checks or tags suspended from rings so
that they are free to swing and do not interfere with the insertion
or removal of the tools. Fig. 8 shows (at the right of the tap
rack) a form of snap gage rack used by the Cleveland Automatic
Machine Co. The gages are held in place by boards having slots
on the edges into which the gage jaws are inserted. .. .1
Rack for Storing Blueprints. When blueprints are kept in
the tool store-room they are often filed in drawers, but this is an
inconvenient and troublesome method and requires more room
than is necessary. When the drawers are filled with blueprints,
i6o
SHOP MANAGEMENT
it is difficult to prevent them from curling up and catching when
the drawer is pulled out, and occasionally a blueprint will slide
out at the rear end. In a shop where considerable trouble had
been experienced with blueprints stored in shallow drawers, the
rack illustrated in Fig. 10 was installed and proved very satis-
factory. This rack is made of 2- by 4-inch timbers to which are
secured a large number of sheet-steel strips upon which the blue-
Fig. 9. (Upper Section) Rack for Snap Gages. (Lower Section)
Bins formed of Steel Partitions
prints are suspended as indicated by the illustration. The
lengths of these steel strips are varied in accordance with the size
of the blueprints, the largest prints being at the bottom of the
rack and the smallest ones at the top. The numbers of the prints
are written on labels and pasted on the steel strips or arms.
Tool Grinding in Supply Room. The grinding of the class of
tools used on turning and planing machines is considered an im-
portant function of the tool store-room in many plants where this
STORAGE AND MAINTENANCE OF TOOLS l6l
system has been put into use. There are a number of reasons
why machine operators are not permitted to grind those tools
that are adapted to be ground by hand. In the first place,
numerous experiments have proved that slight changes in the
shape of a tool of the type used for turning, planing, etc., may
have a decided effect on its cutting qualities and upon the length
of time that the tool can be used before regrinding is necessary;
therefore, it naturally follows that these tools should all be given
whatever shape has proved to be most effective. In other words,
Fig. 10. Rack for Storage of Blueprints
tools should be standardized, especially as regards the shape of
the cutting ends. The development of special tool-grinding
machines and the establishment of tool-grinding departments
in many shops has made it possible to have all the cutting tools
uniform and ground according to approved principles.
Disadvantages of Grinding Tools by Hand. When each man
is independent as to the grinding of tools, the results depend upon
his experience, skill, or interest in doing things the right way.
Some workmen grind their cutting tools properly and others
violate every principle of tool grinding. Correct grinding is
not always done even when the workman knows how different
1 62 SHOP MANAGEMENT
tools should be formed. Sometimes the shape of the tool is
sacrificed in order to grind it quickly or easily. The way an old
shopmate used to grind thread tools illustrates this point. The
plan followed was 'to bevel the top of the face downward toward
the front, because the narrow point of the tool could easily be
ground away. The scheme worked well and the edge was sharp,
but the " negative rake " neither improved the cutting qualities
of the tool nor the form of the thread cut with it.
Another important reason why hand grinding by machine
operators is not regarded favorably by many manufacturers is
that machines are frequently idle while the tools are being ground.
The amount of productive time lost in this way varies with dif-
ferent classes of work and also with the ability of the operator.
Some operators grind dull tools while cuts are being taken, but
the extent of this practice depends upon conditions. The time
taken to sharpen a tool is sometimes increased considerably be-
cause the grinding wheel is naturally more or less of a social
center.
Tools that lie about machines deteriorate in many instances,
their condition often depending upon the initiative of the man
operating the machine ; moreover, in many shops where individ-
ual sets of tools are found, there is little incentive for keeping
tools in good condition. For instance, an operator who under-
stands tool grinding may, as the result of his own efforts, secure a
set of lathe or planer tools that have been carefully forged and
ground, but such tools are often borrowed permanently by other
workmen, so that attempting to keep up a set of tools is rather
discouraging.
When tools of the class referred to are kept in the tool supply
room with the other tqol equipment, but the grinding of such
tools is done by the machine operator, the results may depend
largely upon conditions. In comparing this system with the one
which provides for grinding all tools to standard shapes by means
of a special grinder, instead of by individual workmen, the size
of the plant and general nature of the work should be considered.
In a relatively small shop where a great variety of work is done
by competent machinists, the tools are often ground to suit dif-
STORAGE AND MAINTENANCE OF TOOLS 163
ferent operations and there may be advantages in allowing the
workmen to grind their own tools. Whether or not the size of
the plant will warrant the installation of a special tool-grinding
department for forged tools is another point to be considered,
some contending that such machines should be used in small
shops as well as in those of larger size.
Location of Tool Grinder. The grinding machine used for
sharpening forged turning and planing tools is usually located
either in the tool supply room or in a separate section of this
room; it is also sometimes put in the tool-room or out in the
shop. If there is not enough tool grinding to keep one man
busy, the grinder is generally located where it will be convenient
for the operator whose time is partly given to other work.
In some shops the grinding of forged lathe and planer tools is
done in the department where the tools are forged and dressed.
One method is to first forge the tools to standard shapes and then
rough-grind them on a universal tool grinder before hardening;
after the hardening operation the tools are finish-ground and are
then stored in racks until needed in the shop. This practice of
grinding forged turning and planing tools in the forging depart-
ment has been adopted by the American Machine & Foundry Co.
with satisfactory results. All dull tools are collected daily and
one man grinds nearly all the tools of the class mentioned. The
shops are equipped with grinding wheels so that the employes
may grind their own tools, although this practice is not encour-
aged by the management. It might be assumed that hand grind-
ing would prevail generally, but the fact is that the wheels in the
shop are only used occasionally by men operating the machines,
because they consider that the tools ground to standard forms in
a tool grinder designed for that purpose are superior to those
ground by hand; consequently, the wheels are used principally
for sharpening tools that have been dulled slightly or for making
slight changes in tools to adapt them to special operations.
Stock of Sharp Tools. When sharpened tools are issued from
the tool store-room, it is advisable to have a sufficient number
of each size and shape to last, say, two days before the supply is
exhausted. As the dull tools are returned, they are allowed to
1 64
SHOP MANAGEMENT
accumulate so that a number can be ground at one setting of the
machine. Tools of the same size and form should be ground
successively in order to reduce the time required for adjusting
the tool grinder. Fig. 1 1 shows the rack in which sharp tools are
stored in the tool supply room of the Tabor Mfg. Co.
Fig. ii. Rack in which Forged Turning and Planing Tools are
kept in Tool Supply Room
Maintenance of Tools. A tool store-room where tools are
merely kept while not in use soon contains many tools that are
not fit for service or that, at least, seriously interfere with the
efficiency of manufacturing processes. One of the important
functions of the tool supply department is to see that all tools are
STORAGE AND MAINTENANCE OF TOOLS 165
kept in good condition and that there are enough tools of each
type requiring duplicates to meet the demands of the shop. This
involves sharpening dull cutting tools and replacing or repairing
any tools that may be partly or entirely deranged, either because
of wear or breakage. In large shops, especially, it is also impor-
tant to have some systematic method of investigating defective
tools to determine whether or not they are worth repairing and
the cause of tool breakage, so that the design or construction may
be altered if it is apparent that such changes are necessary.
A tool maintenance system which has proved satisfactory in
a large manufacturing plant is so arranged that the replacement
and repair of tools is done on as systematic a basis as the regular
manufacturing work. If a tool needs to be replaced because of
breakage or excessive wear, the employe must first have his fore-
man sign a " tool release card "; the employe may then return
the tool to the tool crib, where he either receives another one or
the tool check, if another tool of the same kind is not needed.
The release card and the damaged tool are kept together in the
store-room, pending a weekly examination by an inspector who
determines whether or not the tools should be repaired or dis-
carded. In many cases, the tools become defective on account
of long usage, but if it is apparent that the damage is the direct
result of faulty construction or gross carelessness on the part of
the user, steps are taken either to modify the design or to stop the
careless practice.
In case regrinding or repairs are necessary, it is essential to
record in the tool supply room what tools are sent out and to see
that they are returned to the right place. The card or form used
in such cases gives the number of the department in which the
tool is used, the name of the man in charge of the tool crib, the
name of the tool, the nature of the repairs or operation required,
the number of the tool crib, and the order number against which
the time needed for the repairs and any material that may be
required is charged. A copy of this form accompanies the de-
fective or dull tool and is kept in the tool-room where the repair-
ing or sharpening is done, as a record of this work; a second copy
is kept in the tool crib to show what tools have been sent to the
166 SHOP MANAGEMENT
tool-room, and the office also receives a copy, which is held tem-
porarily as a reminder that the work is being done.
When files need to be replaced as a result of wear, a special
order is used. The worn file is taken to the department fore-
man, who examines it and then makes out an order for another
file, if in his judgment the old file should be replaced. On this
order is written the name of the file, the size, the number of files
needed, the department number, the tool crib number, the date,
and the number .of the employe to whom the file should be de-
livered. This order also bears the signature of the department
foreman. The same order is used to obtain new files.
Determining Causes of Tool Breakage. The number of
tools which must be replaced because of breakage can often be
reduced considerably by instituting a systematic method of de-
termining the cause of breakage in each case. A plan which has
proved successful requires the use of printed forms or slips (see
Fig. 12) which are given to all foremen. When an employe
breaks a tool, he must obtain one of these slips from the foreman
in order to secure another tool or the check which has been de-
posited in the tool supply room. The printed slip contains a list
of tools commonly used and blank spaces in which the names of
other tools may be written. If a f-inch tap, for example, is
broken, the size of the tap is marked in the space opposite the
word " tap " on the card. The cause of breakage is indicated
by a cross made by the foreman opposite whatever term on the
card indicates the cause. These forms are filed back of each
man's " record card " and are examined at the end of each week
or month to determine what workmen are breaking the most
tools and the causes for such breakage.
Tool Supply Systems in General Use. In order to determine
what tool supply room system has been adopted most widely by
manufacturers in various parts of the United States, information
pertaining to the more important features has been obtained
from a great many machine-building plants which differ widely
in size and also as regards manufacturing conditions. This in-
vestigation shows that, while details vary considerably to suit
local conditions, there are certain methods of handling small tool
STORAGE AND MAINTENANCE OF TOOLS
167
Check No. f* Foren
All Broken 1
^^h^&in&L
Dept^jL
ed
f<Wls Must Be Return
Name of Tool
No.
Size
Name of Too)
No.
Size
Drill
Tap
Reamer
File
Hacksaw Blade
/
i"
Wrench
Milling Cutter
Cause of Tool Breakage
Carelessness Defective Construction
_X_Accident Defective Machine
Defective Design Defective Jig
equipment which have been employed quite generally. A brief
review of the system which seems to be the most prevalent will
be given.
When a man is first employed he is given a set of tools which
is kept permanently. This set may include files, cold chisels,
bench brushes, or whatever equipment the employe uses in con-