Chapter VI.
MINIMIZING THE TIME OF MACHINE-TOOL OPERATIONS.
TWO fundamental principles of cheap production.
They are of the greatest importance, and yet nine times out of ten a searching investigation will prove that little consideration has been given them in ordinary shop practice in most of the companies at present. They are so closely related that their simultaneous discussion is advisable. They are both essentially "time savers." These two principles are:
1. — The determination of "standard time" for each job and its tabulation, introduction, and enforcement.
2. — The absolute elimination from the workman's routine of every duty but that of running his machine continuously and efficiently; the bringing to him of tools and stock for his next job before he is ready for it.
The first and possibly the more vital of the two is the determination of standard time upon each job — that is, the shortest space of time in which each job should be completed (including setting up), under normal conditions and with due regard to the fullest possibilities and capacity of the machine tool, the cutting tool, and the stock.
An appalling undertaking, this, in most shops, under existing conditions; appalling and seemingly impossible because of lack of knowledge of the best shapes for cutting tools, of the best methods of hardening and grinding, of the results to be secured from the use of high-speed steel cutting tools, of the best methods that can and should be adopted by a skilled workman, of the capacity of the machine tools in the shop, and, worst of all, because of the lack of men skilled in the best methods for handling these cutting tools — men capable of doing the work and of seeing that the workmen do it.
It scarcely seems necessary to argue in favor of this determination of standard time. But in many manufacturing firms, the question of the rapidity of production is determined by e foreman's judgment and skill alone. No man with real shop experience will assert that the average foreman does, or in fact can, know the best results that can be secured in machining today, unless he has been afforded and has accepted exceptional opportunities for making thorough tests of a really scientific character — something that rarely happens. Even should a foreman possess this desirable knowledge, it is beyond the power of any one man to supervise properly any group of men, even though small, so that the high point of efficiency may be assuredly reached, and at the same time do the other work that usually falls to the foreman's lot.
Again, the use of high-speed steel for cutting tools is a development of recent years. Notwithstanding all that has been published on this subject, comparatively few shop foremen really know what the fullest possibilities of its use are, and fewer still ever force their departments to use it to its fullest efficiency even after its value has been recognized. In fact, there have been comparatively few tables ever published that show in a practical maimer just what can be done with it. The machine-tool builders themselves, singularly enough, seem to be unable to give any positive, accurate advice as to the actual conditions of cutting speeds, feeds, and depth of cut under which their own tools can best operate, and even the makers of the tool steels do not provide tables of much practical use.
Nevertheless the work of such a man as F. W. Taylor, in his remarkably thorough and extremely valuable publication, " The Art of Cutting Metals," clearly shows the possibilities that lie in the use of these modem cutting tools — Messrs. Taylor and White being the discoverers of these possibilities and Mr. Taylor himself leading the van in the application to practical use of these principles. This one work makes clear not only the great possibilities but also the great difficulties that originally lay in the path of the investigator. With all of these points in mind, it is simply "rot" to give heed for a moment to any claim of any shop man that his knowledge of this subject is at all exhaustive.
Standard times should be determined by some one, some how. Certainly no one can dispute the fact. Experiments and experience show that the present practices of foremen gives results 40 to 60 per cent short of maximum efficiency. Inasmuch as your entire business is built upon and depends upon the cost of production — or, in its last analysis, simply "the time it takes each man to do his job of work," it is of fundamental importance that that standard time be first determined by methods that will ensure accuracy.
The second cardinal principle of cheap production stated at the outset was " the absolute elimination from the workman's routine of every duty but that of running his machine continuously and efficiently; the bringing to him of tools and stock for his next job before he is ready for it."
The machine hand, assembler, or other worker must be forced to concentrate his skill and attention upon his own work and that work alone, making it impossible for him to waste his time (and thus the employer's money) upon work he should not do. Consider for a moment the many things that a machine hand, for example, will ordinarily do other than operate his particular tool, and then give a moment's thought to analyzing the result. The worst "time wasters" can be classified somewhat as follows:
a. Rxmning to the supply room for stock for a new job. Result, the machine tool is shut down.
b. Getting tools, clamps, etc., from the tool room for a new job. Result, the machine tool is shut down.
c. Grinding his own tools (and very badly at that). Result, the machine is shut down.
d. Excessive time in "setting up" a job, due to lack of proper instruction, or to a tendency to "soldier" because of lack of supervision. Result, the machine is shut down.
e. To these add the fiurther tremendous loss of output because the workman fails to use the proper — the very best — cutting speeds, feeds, and depth of cuts, through either lack of knowl- edge or lack of supervision, and you have a combination that cuts the output of the ordinary shop far below what it should be.
If your shop is running imder ordinary foremanship supervision, with no thorough method for bringing to the workman his stock; for providing him with tools for the next job before he is ready for it; with no method of instructing him what to do and how to do it, and no thorough way of comparing his output with what it should be according to the best standards of today, (mark me ! not your fore- man's standards) — then you can make up your mind that your output is far too low according to the best standards of production.
You may imagine that "carefully calculated" piece-work rates will protect you; but if your piece-work rates have to allow for the conditions stated just above, you are deceiving yourself grossly as to the possibilities of your output.
The important consideration is time! time! Time of the workman running his tool — that is the vital point. Every minute counts for profit if this tool is operating continuously and efficiently; for loss if it operates under the nullifying influences detailed above.
Consider for a moment! Your entire factory investment — building, power plant, transmission plant, all probably built and selected with great care and expenditure of money — is simply to care for and operate the separate units of machine tools, or to house properly your assembling spaces. Your investment in machine tools repre- sents large sums. This vast expenditure is made with but one object in view — that of producing work and producing it as cheaply as pos- sible. Calculate accurately your indirect charges of every character; proportion the total against each machine tool according to the "machine-rate" method of apportionment, and note carefully how large must be the rate per hour for each machine. This will be found to be an astonishingly large proportion of the labor rate per hour and will prove a good index of the great cost of lost time in the shop.
Is it not clear, then, that each machine tool should be, nay must be, brought to as high a factor of operating efficiency as possible? Is not your entire investment made with that one end in view? Does it pay to have the efficiency of any collection of these units reduced 15 per cent to 25 per cent by the existence of such shop methods as those detailed, by which the men operating the machines are actually compelled to shut them down to hunt up their next job, to collect their tools, to grind their tools, and to do many things that should be done for them? Can you afford to suffer an even heavier reduction in effi- ciency due to lack of knowledge of the " best time for each job?"
The importance of these points can be further emphasized by considering that all such delays, which in their total represent a large amount, directly affect cost and profits, output, indirect expense of every description, quick movement of stock, and hence ultimately the amount of working capital needed in the business, and the possibilities of quicker deliveries, with a resultant direct effect upon the sales department and customers. Indeed, aside from the question of costs and profits, nothing is more important to the separate mem- bers of a company— from the executives with their financial problems,through the sales departhient with their selling problems, to the harassed factory manager— than the quick movement of stock.
The reason for the continual absorption of working capital into machinery or stock that worries many a financial officer, or for deliveries so delayed as to affect seriously the efficiency of the selling organization, or for excessive and unreasonable and possibly unex- pected costs that seem and, in fact, are out of reason — the reason for all lies hidden away back in the shop processes and methods. It crops out at the individual lathe, planer, shaper or assembling bench, and then only to the keen experienced eye. The workmen busy? Surely. Look at them hustling! But — see that group around the tool-supply window waiting for tools? How many are waiting at the tool grind- ers to grind their own tools each in his own "iadividual" manner? There is a mechanic who has taken twenty minutes to " set up" his job instead of ten. Then pause and wonder how in the world anyone or two or more foremen can be sure that the men now operating the machines are using proper speeds and feeds and getting the most out of the machine and the tool.
In fact, the causes for all these serious troubles are located so far back toward the fundamentals of production — the individual units affording the causes are so seemingly unimportant, and such is the difficulty of recognizing these conditions, buried as they are in a busy shop — that they are overlooked or ignored.
As a general proposition, the greater the difiiculty of solving such problems the more important and necessary becomes that solution, simply for the reason that in this you are dealing with humane elements to whom is given the opportunity of slowing up in production solely because of that very difficulty that lies within the problem itself and its solution. And yet so fundamental and vital is their importance that they cannot be ignored.
The Starting Point for Minimizing Operation Costs.
Investigation of Existing Machinery.— Any plan for the introduction of proper methods for the determination of standard time and the elimination of wasted time must begin by an investigation of the existing shop machinery — an individual report upon each machine tool, especially touching upon the defects, and a recommendation as to what types should be purchased in the future to meet modem production requirements. This is a matter of great importance, but machinery, designed to stand up under the latest high-production requirements, are recognized and listed up at the beginning of the introduction of any new plans, this important matter is liable to be lost sight of later, with the consequence that when the time for purchases of new machinery does come, the older inefficient types are citing to and the shop is further encumbered with old-style tools.
Nor is the question of securing a more rigid and efficient tool such a simple question as at first appears. Few machine-tool manufacturers are making an earnest attempt to place upon the market tools strong enough to meet the more severe requirements of today. Why? First, because comparatively few have made tests of sufficient scientific worth to determine where the points of greatest weakness really are and how to strengthen them properly. Second — there is the money tied up in old patterns, old stock in the factory bins, in ma- chines going through the process of manufacturing, and finally in finished machine tools carried in the sales rooms. Changes of a radical character would prove a serious matter under such conditions. And, again, the demand of the manufacturer for better and heavier tools has not been urgent enough to force the machine-tool builder into the tremendous trouble that a thorough redesigning of the older types would surely cause. Therefore the latest product of a machine- tool manufacturer is not necessarily adapted to the methods of production that I am advocating.
Greater driving power is usually the first requirement. Accurate tests have shown that modern lathes, for instance, should have fully double the driving power usually contemplated in their design. This is a point that must be considered carefully. Of course a proper increase in driving power of a lathe, for example, means wider cones, heavier bearings, and stronger heads. Immediately there follows the question of the rigidity of the bed. It is at once apparent that this is a very important point, and yet too little attention has been paid to the design of bed best suited for withstanding the strains and stresses due to the use of new high-speed cutting tools. Solidity is very necessary. The consideration of the need of strength and rigidity should certainly be applied to the tail stock. Slide rests and tool holders should be simple and strong. The tool must be held rigidly under all conditions. The tool posts should be set down lower than is customary in everyday practice. Under modem conditions much greater feeding power is needed.
But however certain we may be that defects in machine tools have a direct effect upon the rate of production and the cost of the product, existing conditions may prevent purchase of new tools. Inasmuch as I have been through the mill several times with nm-down concerns, I appreciate fully the fact that most manufacturers are obliged, through sheer financial stress, to ignore any scheme, no matter how promising, that involves at the outset a thorough replacement of the existing machinery with the most modern types, even though it can be demonstrated that the latter are 50 per cent more efficient.
The practical question that confronts many a manager is: "What on earth can I accomplish with my present old' rattle traps' of machine tools? I couldn't buy gold dollars for 98 cents if I had to pay cash, much less spend thousands for replacing my present machinery. I must first make good with what I have. After we are on firm ground we'll talk about stronger and better machine tools."
True! Very true! A viewpoint very often overlooked by the manager, or by the man who has this work in charge but doesn't have to produce the dollars to "keep the old ship afloat." This latter situation, which is a stern actuality with many a man who is eager to improve conditions, is all compelling and must give shape to the preliminary methods of procedure. This I shall try to keep in mind.
Granting, however, the hard fact that many concerns are obliged first to dig out the problem, using their existing facilities, it is of all the greater importance that two reports relative to machine tools be made out: —
First, a report showing what heavier, stiffer, and more efficient types of machines should be substituted for existing types when the proper time comes.
Second, a full report upon each and every machine tool in the shop, showing its points of weakness and its limitations in cutting speeds, feeds, and depth of cuts ; how it can be strengthened ; a description of the kind of work that should be done on it ; a record of best times on jobs ; a full statement of the best machine tool to substitute for it, and a clear-cut comparison of possible production by the use of the latter machines.
I warn you again that unless this be done systematically at the start, it probably never will be done ; then as time goes on you will find yourself burdened with many a newly purchased machine tool just as weak and inefficient as the older one it replaces.
In considering the problems of increasing production in any particular shop, we find therefore that they become problems of devising methods and making tests upon the supposition that existing machines and facilities must be used in regular production — that, however advantageous the latter types of tools, the important question of lowering costs must be considered on the basis of developing to the uttermost the efficiency of the present machinery. We must there- fore keep in mind these points in the building up of our system. The great importance of gathering all our data systematically and of using them scientifically cannot be too strongly insisted upon.
PEOFIT MAKING IN SHOP AND EACTORY MANAGEMENT
BY
CHARLES U. CARPENTER
NEW YORK
THE ENGINEERING MAGAZINE
1908
Copyright, 1908
By JOHN R. DUNLAP
https://archive.org/stream/cu31924002748576/cu31924002748576_djvu.txt
CONTENTS.
Chapter I. The Reorganization op a Run-Down Concern
The Necessity for Analysis of Existing Conditions — ^Advantageous Posi-
tion of a Well Organized Concern — The Manufacturer with his Eyes Closed —
The Manufacturer with his Hands Tied — Organizing the Methods of Inves-
tigation and Analysis — The Usual Defects of Organization, System and
Methods in Manufacturing Plants — ^The Superintendent — ^The Foremen —
Job Bosses and Workmen — Systems of Pay and their Effect — ^The Stock
System — The Order and Tracing System — ^The Cost System — ^Machining
Methods — Defects of the Sales Department — Defects of Executive Con-
trol 9
Chapter II. The Practical Working op the Committee System
No Ready-Made System is a Panacea — ^Why New Systems so Often
Fail — Co-operation of the Working Force is Essential — ^The Human Element
and the Get-Together Spirit — Formation of the Committee System — ^The
General Factory Committee — Its Personnel — Its Work — Its Meetings —
Subsidiary CoHimittees — Job Bosses' Meetings — General Foremen's Meet-
ings — ^The Workmen — Promotions 23
Chapter III. Reports; Their Necessity and Their Uses
The Necessity for Reports of Varied Kinds — ^What they should be and
what they should Cover — A General Outline of the Essential Reports — ^The
Monthly Analyzed Profit and Loss Sheet — ^The Sales Reports — ^The Factory
Reports — ^The Cost Reports — ^The Points to be Shown and the Methods of
Use 36
Chapter IV. The Designing and Drafting Department
Results to be Secured — Close Relations with the Tool Room — Require-
ments of an EflScient Drafting Department — ^Meetings with the Com-
mittees — Co-operation with Shop Foremen — Standardization in Design —
Designing for Cheap Machining and Assembling — ^Making and Following
of Drawings to be Invariable — Reports from Machining and Assembly
Departments — ^The Use of the Coiimaittee System 42
Chapter V. The Tool Room; the Heart op the Shop
The Full Functions of the Tool Room — Systems of Tool Supply —
Speed of Production in the Tool Room of Vital Import — ^Methods for
Hastening Production — ^The Choice of the Foreman — Specialization of
Labor — Standaxdization — Duplication of Standard Parts — Subdivision of
Labor — ^The Small Shop — Speeding up Tool Production and Checking the
Cost — Tool-Cost Cards — Examples — ^Method of Use — Tool-Room Commit-
tee Membership 50
Chapter VI. Minimizing the Time of Machine-Tool Operations
The Determination of Standard Times — ^The Concentration of the Work-
man's Time on Running his Machine — ^The Adoption of High-Speed Steel —
Causes of Lost Time — The Starting Point in Minimizing Operation Costs —
Investigation of Existing Machinery — Systematic Report upon Improve-
ments in Old Machines and Recommendations for Replacements or New
Purchase 64
Chapteb VII. Possibilities Attending the Use of High-Speed Steel
What Percentage of Increase may be Expected in the Output — ^The
Abundant Provision of Cutting Tools — Standard Shapes for Tools — ^How
Determined — Forging — Hardening — Form for Records — CooHng — Grind-
ing — Use of Automatic Grinders 73
Chapter VIII. The Determination or Standard Times por Machining
Operations
The Shop Conditions upon which Standard Times Depend — Tests of
Times which should be Attained — ^How to Begin — Classification of Parts —
The Expert Tester — ^His Qualifications — Practical Speeds in Lathe Work —
In Planer Work — In Drilling — ^Tables — How to Use the Tables — ^The Com-
mittee at Work — Requirements for Maximum Production by the Work-
man 83
Chapter IX. Standard Times for Handling the Work
The Elements which must be Considered — Causes of Lost Time in Hand-
ling—Injuries to Stock or Parts in Handling — ^The Use of Standard Boxes —
Standard Places for Stock and Parts — Records of Handling Times —
Forms — Setting-up Time— Times for Work on the Machines — ^Time for
Removing Work from the Machines — ^The Use of Committee Action 94
Chapter X. Standard Times for Assembling
Special Difficulties to be Found in this Subject — ^Methods of Procedure
which Succeed — Examples of Results Secured — ^An Instructive Case
Described — ^Foremen's Co-operation Essential — How it can be Enlisted. . . . 101
Chapter XI. Stimulating Production by the Wage System
The Attitude of the Workman — ^Mischief Caused by Cutting of Rates —
The True Theory of Costs — ^The Wage Problem in Introducing Standard
Times — ^How to Get the Workman to Stand for Them — Systems of Pay —
Day Work — Piece Work — Premium Plan — ^The Differential Plan — ^The
Bonus Plan — Special Modifications of the Bonus Plan Recommended 109
Chapter XII. Stock and Cost Systems as a Factor in Profit Making
The Prime Requisites of a Cost System — Wha,t it should Accomplish —
The Three Fundamental Problems at a Stock System — A Simple and Suc-
cessful System Described — ^The Forms and Cards and their Mode of Use —
Storage Platforms and" what they AccompUsh — Stock-Tracing and Cost
Sheets — ^Forms — ^How the Data are Used 116
Chapter XIII. The Upbuilding of a Selling Organization
The Various Methods of Selling Manufactured Goods Defined — ^What is to
be Considered in Developing a Selling Force — ^Training of Salesmen — Its
Possibilities Proved — Development of a Selling System — Salesmen's Demon-
stration Meetings — A Typical Programme — ^Modes of Stimulating Interest —
Salesmen' Training Department — Selection of an Instructor— Prepara-
tion of a Manual — Reports and their Importance — ^Forms — Lists — Adver-
tising ._ 124
Chapter XIV. Effective Organization in the Executive Department
Difficulties Peculiar to the Executive Division — The Personal Element —
The Use of the Report System — Reports from the Selling Division — ^Forms
— Factory Reports — ^Forms — ^Executive Reports — ^Forms — The Methods
Illustrated by an Example and a Typical Programme — ^The Results
Secured 138
About Carpenter
https://en.wikipedia.org/wiki/Charles_U._Carpenter
Charles Underwood Carpenter (Indiana, January 1872 – January 15, 1928[1]) was an American business manager, management author, and inventor, known as "one of the earliest advocates of the committee system in factory management."
Carpenter got his degree from Princeton University in 1893, and started his career in industry.
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