.DIES,-

THEIR CONSTRUCTION AND USE

FOR THE

Modern Working of Sheet Metals.

A. TREATISE

ON THE DESIGN, CONSTRUCTION AND USE OF DIES, PUNCHES,

TOOLS, FIXTURES AND DEVICES, TOGETHER WITH THE

MANNER IN WHICH THEY SHOULD BE USED IN

THE POWER PRESS, FOR THE CHEAP

AND RAPID PRODUCTION OF SHEET

METAL PARTS AND ARTICLES.

FUNDAMENTAL DESIGNS AND PRACTICAL POINTS BY WHICH SHEET METAL PARTS MAY BE PRODUCED AT THE MINIMUM OF COST TO THE MAXIMUM OF OUT- PUT: WITH SPECIAL REFERENCE TO THE HARDENING AND TEMPERING OF PRESS TOOLS, THE USE OF FILES, AND TO THE CLASSES OF WORK WHICH MAY BE PRODUCED TO THE BEST ADVANTAGE BY THE USE OF DIES IN THE

POWER PRESS. f UNIVERSITY }

OF BY

JOSEPH V. WOODWORTH.

Illustrated by .'0.7 Engravings.

YORK: BTN-ILtEY & CO.

132 NASSAU STREET 1903.

HALLIDIE

COPYRIGHTED 1902

BY NORMAN W. HENLEY & Co.

TO FREDERICK «J. BRYOJST,

THE AUTHOR'S FRIEND AND ASSOCIATE,

WHOSE KINDLY INTEREST AND ENCOURAGEMENT WILL EVER BE REMEMBERED, THIS HOOK IS AFFECTIONATELY DEDICATED.

PREFACE.

The use of the power press for the cheap production of sheet metal parts (both large and small) has progressed in a truly won- derful manner during the last few years, and, by the adoption and use of suitable dies and fixtures, this modern machine tool has demonstrated its efficiency for turning out work formerly (and even now in a large number of shops) produced by the milling- machine, the shaper, the drill press and the forge. Especially is this so where the parts required are of flat soft steel or iron ; and in not only one line of machine manufacturing has the power press been used in this manner, but in every line.

The management of the manufacturing establishments in which the power press has been adopted for the production of parts as referred to above, understand and appreciate the full value of dies ; and in such shops they and the machines in which they are used have become as great factors in production as any of the other tools in general use.

The rapidity with which the use and adaptation of dies and press fixtures are becoming understood, the endless variety of articles which they turn. out, and the great numbers of mechanics who are in various ways engaged in devising and constructing such tools, have suggested to the author that a practical, compre- hensive treatise on this subject would be of value and interest to all persons who might be in any way interested in modern sheet- metal working.

In writing this book the author has done so with the purpose of giving to practical men a book which would treat these pre- eminent factors in modern manufacturing — Dies — as they should be treated ; and that is, from the viewpoint of a practical man. In the pages following are shown engravings of dies, press fixtures and sheet-metal working devices, from the simplest to the most intricate in modern use, and the author has endeavored to describe their construction and use in a clear, practical manner, so that all grades of metal-working mechanics will be able to understand thoroughly how to design, construct and use them, for the pro-

8 PREFACE.

duction of the marvelous variety of sheet-metal articles and parts which are now in general use, and form an integral part of our twentieth century civilization. Many of the dies and press fixtures shown and described herein were constructed by the author, others under his supervision ; while others were constructed by some of our most skillful mechanics and used in some of the largest sheet- metal goods establishments and machine shops in the United States. A number of the tools shown have been selected from over 150 published articles which have been written for the columns of "The American Machinist," "Machinery" and "The Age of Steel," under the author's own name and various pen names. For a number of practical "points" and "kinks" which have been written into the text of the volume the author acknow- ledges his indebtedness, with thanks, to the following individuals and establishments : Mr. J. E. Fillman, Brooklyn, N. Y. ; Mr. W. B. Bailey, Brooklyn, N. Y. ; Mr. Robert Leith, Hoosick Falls, N. Y. ; Mr. Walter J." Woodworth, Brooklyn, N. Y. ; Mr. Charles Colligan, Hartford, Conn. ; E. W. Bliss Company, Brooklyn, X. Y. ; The Cleveland Punch and Shear Company, Cleveland, O. ; Perkins Machine Company, Boston, Mass. ; Nicholson File Company, Providence, R. I.

We have endeavored to keep all obsolete matter out of this volume, and to make every die and device and press shown repre- sent the highest that has been attained in the development of each type described. The description of -the construction and appli- cation of the tools, it is to be hoped, will enable the practical man to adopt them for the production of sheet-metal parts and articles to the maximum of output at the minimum of cost and labor. It is the earnest wish of the author that a perusal of the contents of this volume will enable all who may be in any way interested in sheet-metal working to contribute to the manufacture of sheet-metal parts in a manner which is up-to-date, both as to efficiency and working qualities of the output and to cheapness in production.

Of the origin or antiquity of the art of sheet-metal working the author knows very little ; and although he realizes that the marvelous numbers of ingenious tools and devices which are used to-day to produce articles ranging from the modest trouser button to the massive boiler head are but the results of a long course of evolution, he is convinced that a treatise describing the tools and devices of the present day is what the practical man wants.

PREFACE. 9

Although the origin and history of obsolete methods and tools may be of interest to the antiquary, the present-day machinist prefers to spend his hours of leisure in acquainting himself with the design, construction and use of tools with which he may in- crease the output and lower the cost of production, and thereby increase his earning capacity. With this object in view, and trusting that all metal-working mechanics may be helped by it, this book is modestly submitted to the public.

JOSEPH V. WOODWORTH. Brooklyn, N. Y., November, 1902.

CONTENTS.

CHAPTER I.

THE CONSTRUCTION AND USE OF "SINGLE" OR BLANKING DIES, AND "DOUBLE" OR PIERCING AND BLANKING DIES.

Introductory — Steel — The Construction of a Simple Punch and Die —The Bolster— The Die Blank— The Templets— Working the Templet through the Die — Giving Clearance to the Die — Locat- ing the Piercing Dies — Hardening a Blanking and Piercing Die — Making the Blanking Punch — Locating the Blanking Punch in the Punch Plate— Locating the Piercing Punches in the Punch Plate — Finishing the Die — Fundamental Points to be remembered — Setting the Die and using it — A Plain Blanking Die — Dies for Large Blanks — The Use of the Power Press — Open-back Presses — Lining up and Leveling a Power Press — Using the Proper Tools — A Press for Small and Medium- Sized Parts 17 to 37

CHAPTER II.

SIMPLE DIES FOR USE IN THE MACHINE SHOP.

An Emergency Die — A Shearing Die for finishing Heavy Blanks — Burnishing Dies — Dies for finishing Holes in Heavy Stock — A Curling Die for a Hinge — Die for Curling Metal Tubes — A Washer Die — A Burnishing Die for finishing Heavy Blanks — A Bending Die for Right-Angle Bends — Planing the Angle on Die Blanks — Blanking and Bending in One Operation — Punching Heavy Stock— A Set of Dies showing how Sheet Metal may be drawn and formed into Various Shapes — Form- ing Dies for Square-grooved Tubes 38 to 60

CHAPTER III. "GANG" AND "FOLLOW" DIES — HOW TO ADAPT AND USE THEM.

The use of "Gang" and "Follow" Dies — A Simple Gang Die and its Work — A Gang Die for a Sheet-metal Bracket — A Gang Die for Metal Tags — A Gang Die and Two Forming Dies for Umbrella-rib Tips — A Gang Die for an Odd-Shaped Piece — A Gang Die for producing the Blank cf a Compass Sliding Bracket — A "Follow" Die which draws, pierces, end-finishes, outs off and bends in One Operation — A Complete Set of Dies

12 CONTENTS.

for the Manufacture of Sheet-Metal Hinges — An Automatic Combination, Piercing, Bending and Twisting Die for Box- corner Fasteners 61 to 92

CHAPTER IV.

THE ADAPTATION AND USE OF SIMPLE DIES AND PRESS FIXTURES FOR THE ECONOMIC PRODUCTION OF SHEET-METAL PARTS.

The Power Press in Agricultural Machine Work — Punching a Mild-steel Strap — Seeing Power Presses at Work — Piercing, forming and punching Heavy Blanks in One Operation — Mak- ing Pinions and Racks by Punching — A Set of Dies for a Fun- nel-ended Tube — A Set of Dies for a Sheet-metal Bracket — A Double-blanking Die, a Piercing, Cutting-off and Forming Die, and a Large Double-Blanking Die — Punches and Dies for pro- ducing Parts of an Electric Cloth-cutting Machine — An Arma- ture Disk-notching Die with a Dial Feed — Dies for Switchboard Clips — A Cutting-off and End-finishing Die, and an Accurate Sectional Die with a Chute Feed and Finger Stripper 93 to 128

CHAPTER V.

BENDING AND FORMING DIES AND FIXTURES.

Bending Dies, Simple vs. Intricate — Dies for making a Large "Safety" Pin — Forming a Funnel-ended Tube — Bending Dies for Wire Lock Clasps — A Bending Die for Wire Staples — An Automatic Wire-bending Die — Cutting, perforating and shap- ing in One Operation — Blanking and Stamping in a Press with Automatic Slide — Feed and Ejector — Two Bending Dies for Flat Stock — An Automatic-slide Forming Die for a Sheet-metal Ferrule — A Press with an Automatic Device for Tube Form- ing— Bending and Forming Dies for Round Work — Bending and Closing-in Dies for Round Work — Foot Presses and Outfit of Dies for producing Five-gallon Petroleum Cans— A Double- Crank Press and Outfit of Bending Dies — A Pickeye Forming Press with Dies in Position — Four "Follow" Dies for Bending and Forming — A Special Forming Die — Two Can-body Bend- ing and Forming Machines — An Inclined Press with Dies for Stamping and Bending Body Blanks for Petroleum Cans — A Novel Bending and. Forming Die 12910176

CHAPTER VI.

PERFORATING DIES AND PROCESSES FOR THIN AND HEAVY STOCK.

The Use of Perforating Dies — The Construction of a Simple Pierc- ing Punch and Die — Piercing Two Holes in Opposite Sides of a Drawn Shell — Fixtures for Perforating Burner and Other

CONTENTS. 13

Shells — Press with Cam-actuated Stripper for Perforated Metal — Piercing and Blanking Armature Disks in One Operation — A Quadruplicate Automatic Slide Die for Piercing Conical Shells — Regular and Staggered Perforations — Perforating Press with Automatic Spacing Table — Double Roll-feed Per- forating Press having Lateral Feed for Staggered Patterns in Perforated Metal — Perforating Single Rows of Holes — The Construction of a Special Punch Press for Perforating Tin Ferrules 177 to 202

CHAPTER VII.

CfRLING, WIRING AND SEAMING PROCESSES.

The Terms Denned — Use of the Tools — Curling Dies — Funda- mental Principles — Action of the Metal — Wiring Dies for Shell Work— A Curling Punch and Die for Milk Pans— A Curl- ing Punch and Die for Deep Shells — Wiring Large Shells — Horizontal Dial Press With Pick-off Attachment — Horning, or Seaming, Tools and Presses — Duplex Folding and Seaming for Locked Seams — Double Seaming of Flat, Round Deep Bot- toms— A Double Seaming Machine with Blank Centering De- vice and Collapsible Chuck — Double-seaming Oval, Oblong, Square Shapes, etc. — Rolling Seams on Square Cans 203 to 225

CHAPTER VIII.

DRAWING PROCESSES FOR SHEET METAL SHELLS.

Scarcity of Mechanics Who Understand Drawing Processes— Un- certainty as to the Best Means to Adopt— Types of Dies in General Use for Producing Drawn Shells — Combination Dies —Their Use — Spring Pressure Attachment for Combination Dies — Double-acting Cutting and Drawing Dies — Their Use — Plain Drawing Dies and Redrawing Dies — Drawing Dies With Inside Blank-holders— Triple-action Drawing Dies— The Making of a Combination Die, for Blanking and Drawing a Shell in a Single-action Press — Simple, or "Push-through," Drawing Dies — Drawing Small Shells from Heavy Stock — Making an Accurate Combination Blanking and Drawing Die —Making the Drawing Punch— The Drawing Die— The Die Bolster— Finding the Blank— Machining the Cutting Die— Fin- ishing the Punch— Using the Die— Constructing a Solid-back Combination Die for Shallow Rectangular Shells— Making the Templets and the Drawing Punch — Machining the Drawing- Portion of the Punch Proper— One Way of Finding the Blank for a Rectangular Shell— Finishing the Blanking Portion of the Drawing Die— Locating the Drawing Punch Within the Die— Hardening the Cutting Die— Finishing a Square Blank- ing Punch— Use and Action of the Die— A Set of Dies for Rec-

14 CONTENTS.

tangular Decorated Tin Boxes — First Operation for Rec- tangular Shells — Fundamental Practical Points for Making Ir- regular-shaped Drawing Dies — Trimming and Re-drawing Die for Second Operation — The Use of Trimming Dies for Drawn Work — The Beading of the Shell — Rules for Figuring the Ap- proximate Size of Blanks for Drawn Shells — The Drawing and Forming of Aluminum 226 to 268

CHAPTER IX.

COINING PROCESSES — PUNCHES AND PRESSES FOR OPERATIONS ON HEAVY

STOCK.

The Philadelphia Mint — Coining Processes — An Embossing Press for Work Requiring Heavy Pressure — Punching Tools for Heavy Work — Double-crank Presses for Operating Large Cut- ting Dies — Heavy Notching Press with Punch and Die in Po- sition—Heavy Disc Punching — Steam-driven Multiple Punches — Multiple Punch with Hand-feed Spacing Table — Heavy Beam Punching — A Beam-coping Machine with Coping Dies in Posi- tion 269 to 285

CHAPTER X.

THE FEEDING OF SHEET METAL TO DIES — LUBRICATION OF PRESS WORK.

Feeding of Stock a Factor in Production — Hand Feeding — Single- roll Feed — Double Roll Feed — Feeding Partly-finished Parts and Articles to Dies — The Feeding of Parts which have been pre- viously punched — Double-roll Feeding for Producing Small Pierced Blanks from the Strip — Double-roll and Lateral Feeds — Double-roll Feed with Automatic Release — Dial Feeds — The Friction Dial Feed— The Ratchet Dial Feed— A Press with Adjustable Punch Carriers and an Automatic Friction Dial- feed — A Double-action Gang Press with Special Automatic Feed — Lubricants to Use in the Working of Sheet Metal. .286 to 303

CHAPTER XI.

ANNEALING TOOL STEEL, AND HARDENING AND TEMPERING PROCESSES FOR

PRESS TOOLS — INCLUDING HINTS AND SUGGESTIONS ON THE PROPER

USE OF FILES.

Annealing Defined — Hardening Defined — Tempering Defined — Heat- ing Defined — Hardening and Tempering Small Tools — Hard- ness and Toughness in Steel — Special Methods of Hardening Steel — Hardening Compounds — Tempering in the Sand Bath — Hardening the Walls of a Hole — Reannealing After Roughing —Water Annealing — Warping of Tools in Hardening — The Location of the Hardening Furnace — Hardening Very Small

CONTENTS. 1 5

Parts — Tempering in Oil — Straightening Hardened Pieces Which Have Warped — The Use of Fire Clay in Hardening — Hardening Dies — Hardening Fluids for Dies — Steel for Punches — Soft vs. Hard Punches and Dies — Judgment and Carefulness in Hardening — The Use of Machine Steel for Press Tools and the Hardening of it — Hardening Large Steel Ring Dies so as to Prevent Cracking and Excessive Warping. — The Effects of Previous Annealing in Hardening — Harden- ing Thin Disks — A Welding Kink — Hardening Thick Round Dies — Hardening Springs — A Substitute for Borax in Weld- ing—Hardening Poor Steel — To Anneal Doubtful Steel — An- nealing in Bean Water — Bluing Bright Steel Sheet-metal Blanks — Machining Mild-steel Forgings — Laying Out Dies — Cutting Aluminum — Softening Chilled Cast-iron Dies for Drilling — Hints and Suggestions as to the Proper Method of Using Files — Convexity in Files — Files Properly Handled — Devices for Holding Files — Bent Rifflers — An Improved Surface File Holder — Height of Work — Grasping the File — Carrying the File — First Use of a File — Draw-filing — Preparing Work — Pickling the Work— When Oil Should not be Used— When Oil May be Used — Cleaning the File — Care in Putting Away Files 304 to 329

CHAPTER XII.

MISCELLANEOUS DIES,, PRESSES, FIXTURES, DEVICES AND SPECIAL ARRANGE- MENTS FOR SHEET METAL WORKING.

Artistic Die-making — Dies for Punching Leather Shoe Tips — A Cheap Grinder for Round Dies — A Compressed-air Drop Ham- mer for Making Sheet-metal Caskets — A Special Blanking and Piercing Die — The Cutting of Armature Disks — The Cut- ting of Armature Segments — A Multiple Piercing and Projecting Punch and Die — Drawing and Punching Con- tinuous Strips of Hemispheres — Watch and Clock Makers' Power Press for Sub-press Work — An Automatic Trim- ming Machine — A Beading Machine — A Double-head Crimp- ing Machine — Hand Bending Fixtures — A Combination Blank- ing Die for Heavy Stock— Tool Holder and Tools— Self- Hardening Steel — Rules for Calculating the Speed of Power Presses , 330 to 372

.

CHAPTER I.

THE CONSTRUCTION AND USE OF "SINGLE" OR BLANKING DIES, AND "DOUBLE" OR PIERCING AND BLANKING DIES.

INTRODUCTORY.

In this, the opening chapter, we will illustrate and describe dies which, if adopted, will supersede processes for the produc- tion of metal parts which are now obsolete in a large number of machine manufacturing establishments. The only reason for their non-adoption in other establishments is that their applica- tion and use are not understood. In such shops, where these strictly up-to-date methods are not being used, special tools and fixtures are being constantly designed and constructed for the machining and finishing of metal parts by milling, drilling or other means, which could be accomplished in half the time by means of dies of simple and most inexpensive construction, in the power press. Aside from the reduced cost of production, the lightness, interchangeability, and fine finished appearance of sheet-metal blanks add greatly to the appearance of the machines to which they are attached, and in many cases improve the working qualities as well.

Let any manager of an establishment which does not number a power press or two among its machine tools stroll through his shop with a power press catalogue in his hand and he will not go far before realizing that he is paying for a lot of unnecessary work. After finishing his inspection he will lose no time in placing an order for a power press, and his toolmakers will be kept busy for some time constructing sets of blanking, piercing, bending, shearing and finishing dies to take the place of expen- sive milling, drilling and polishing fixtures.

Steel.

In no branch of the machinist's art should more attention be given to the importance of the proper selection of steel than in die making, as the working qualities of the tools when finished

l8 DIES, THEIR CONSTRUCTION AND USE.

and their efficiency depend upon this more than anything else.

When ordering steel which is to be used for dies be sure to specify that annealed steel is wanted, as the saving of time and labor in the working of it and the results in the hardening and tempering of the finished tools will be a source of gratification to the die-maker. When these results are considered the slight extra cost of annealed steel is insignificant.

As to the grade of steel to use ; be sure to get a good grade, and as there are several brands of steel on the market which are used principally for dies and punches no difficulty should be experienced in procuring a grade or brand which will prove suitable for any special class of work.

When steel forgings are required the job should be given to a smith who understands this branch of his art, as in order for the forgings to machine well and allow of being hardened and tempered as desired, so that the finished tools will accomplish the required results, the smith must understand such work.

The Construction of a Simple Punch and Die.

During a long experience in the making of dies the author has come to know of a number of different methods for con- structing single blanking dies, and double or piercing and blank- ing dies. Every one of these methods has possessed some little kink or way by which the desired results might be accomplished in a manner superior to other methods. So after getting together the best and most practical kinks and ways of all methods, the method of construction here described and illustrated has been evolved.

The Bolster.

Before taking up the description of the die, we will devote a short space to the die-block or bolster. Although these bolsters are made in a variety of shapes and sizes, the one shown in Fig. I is of a type most generally used for fastening and locating the kind of die indicated. A number of different styles of bolsters for blanking and piercing dies are shown in Figs. 2 to 5. A large number of shops, which make dies for their own use, make a bolster with each die, so as to leave the die permanently within it. But for economy, where dies of an average shape and size are used, two or three are all that are required. When a num-

THE CONSTRUCTION AND USE OF BLANKING DIES. 19

ber of dies are kept in action all the time, or at the same time, then, of course, each die must have a separate bolster.

FIG. I. — THE BOLSTER.

In the preparation and machining of the bolster, first a cut should be taken off the top and bottom, and then a finishing cut

FIGS. 2 TO 5. — TYPES OF BOLSTERS.

20

DIES, THEIR CONSTRUCTION AND USE.

off the bottom, after which the face or die seat may be planed to an angle of 10 degrees, as shown, this being a standard taper for die blanks among die-makers. The slots C C are cast in the position shown, in width sufficient to allow of clearance sideways for the fastening bolts with which it is afterward secured to the press. The hole D, in the center of the bolster, should be large enough for the largest blank, from the set of dies which are to be used in the bolster, to drop through after being punched.

The Die Blank.

In Figs. 6, 7 and 8 are shown a double punch and die used

for the production of blanks like Fig. 9; this die is of a type in general use. The punch and die consist of the following parts : The punch holder or stem A, of cast iron, the punch plate or pad B, of mild steel, the blanking

0

0

o o

o

Plan View of

Die

FIG. 6.

FIG. 7.

punch C, of tool steel, the piercing punches D, of the same, the stripper and gage plates E, the die F, of tool steel, and the pilot pin G. The shape of the piece to be produced in a die of this type may be any circular or irregular shape desired, as the method of construction here shown is applicable to all, excepting when the blank to be produced is of a very large size or when the metal to be punched is very thick.

As most presses in which punches and dies of this type are used require a punch holder with a round stem, we show one of this sort. When machining the holder great care must be taken to get the working surfaces square with the stem ; the faces of the punch plate and stripper plate must be perfectly

THE CONSTRUCTION AND USE OF BLANKING DIES.

21

parallel. When planing the die no great care is required, as it has to be ground after hardening. It should be finished with leveled sides, to fit the bolster, with the edges of the face smooth so as to have a square edge from which to lay out the die.

We will now lay the punch plate, punch holder and stripper plate aside, as they will not be touched until the die proper has been finished.

The Templets.

Now in order to lay out the die a templet or master blank is required ; this should be made from sheet steel about 3-32 inch thick, and should be filed and finished all over to the exact shape

End View

FIG. 9. — MALE TEMPLET

FIG. 8.

FIG. 10.

and size required. The two holes should then be laid out in the exact location desired and drilled and reamed to size. Care and accuracy in the preparation of the templet are necessary, as the quality of the work to be produced depends on it. Now take a piece of, say, ^-inch brass rod about 2^ inches long, and solder one end of it to the back of the templet as shown in Fig. 9. The templet is now complete and there is no possibility of getting the wrong side up.

We now take a piece of soft sheet brass, of the same thick- ness as the templet, and bend it to the shape shown in Fig. 10, that is to fit across and over the face of the die with the bent ends projecting down the inclined sides of the die about 5-16 inch.

22 DIES, THEIR CONSTRUCTION AND USE.

This is the female templet, and it should be long enough to allow of its being worked out in the center to fit the male templet, Fig. 9. After having done this the face of the die (which should be polished with a rough piece of emery cloth) should be "blue- stoned" and the female templet placed upon it in the proper position, and an outline of the blank marked through it on the face of the die with a sharp scriber. We now remove the templet and proceed to finish the blanking die, which must be accom- plished by working the blank through it.

Working the Templet Through the Die.

To work a templet through a die proceed as follows: After the surplus stock has been removed by drilling holes about 1-64 inch apart around the inside of the outline and drifting it out, file through from the back to within a shade of the line. Now take the male templet and, holding it by the end of the brass rod, enter it into the die from the back, holding it as parallel as pos- sible with the face of the die. By holding a piece of white paper in front of the die it will be noticed that the die touches the templet at only a few narrow spots ; take a lead pencil and mark these spots, making a line at each spot as long as the surface touched. Now remove the templet and file where the marks appear. Keep inserting the templet, marking the spots and filing them away, and in a surprisingly short time the templet will be even with the face of the die, which will be the exact shape and size desired, fitting the templet perfectly.

There are a great many dies of this type in use (which are used for cutting out blanks which are not required to have smooth sides) that it is not necessary to finish the insides smoothly. But there are a greater number in which the finish of the blanks with smooth sides is one of the objects sought. In dies for producing smooth and well-finished blanks the insides should be finished highly, either with a dead smooth file or a scraper.

Giving Clearance to the Die.

In giving clearance to a die a few things must be considered in order to decide upon the proper amount to give. For a die which will only be used to produce a few thousand blanks excessive clearance should be given, say, five degrees, as this

THE CONSTRUCTION AND USE OF BLANKING DIES. 23

will allow of the die being finished quickly. In dies which are to produce large quantities of blanks, and in which the blanks produced are required to be of approximately the same size, one degree is plenty. In giving this one degree of clearance to the die so that it will have one degree of clearance all the way through, the holes that are drilled to allow of removing the surplus stock should be reamed from the back with a reamer of about the taper of 1-32 inch to I inch of length. The reaming of the holes when constructing a blanking die will save a vast amount of filing and the giving of the one degree of clearance will not be difficult.

Locating the Piercing Dies.

The next step in the construction of the die is the locating of the two piercing dies. To accomplish this, place the master blank within the female templet and clamp it to the face of the die in the correct position, allowing for a thickness of metal between blanks. We now take a center drill, which fits the holes in the master blank, and transfer the two holes through it to the face of the die ; we drill these holes and then ream them from the back with a reamer of the same taper as the one used for the blanking die. After the holes for the dowel pins and screws by which the stripper and gage plates are to be fastened to the die have been drilled and tapped, and the hole for the stop pin located and drilled, we are ready to harden and temper the die.

Hardening a Blanking Die.

In order to harden a die properly great care should be taken ; first in the heating of the steel, and second in the quenching. In all shops where dies, or other tools which require hardening, are constructed, a gas furnace or "muffler" should be used for heating them. But when a "muffler" is not handy charcoal should be used. After a good clean fire has been built, all screw and dowel holes in the die should be plugged with fire clay or asbestos. By taking these precautions the tendency of the steel to crack around the holes is, as far as possible, eliminated. We now heat the die to an even cherry red, so that the entire plate will be the same temperature; then remove it from the fire and dip it endwise into the water (which should be warmed slightly

24 DIES, THEIR CONSTRUCTION AND USE.

to take the chill out), being careful to dip down straight, and not to move it or shake it around, as that would increase the possibility of the die warping or shrinking excessively. After removing the die from the water it should be immediately warmed. Now grind the face of the die; heat a thick piece of cast iron red hot, and place the die upon it; it can then be drawn evenly to any temper desired. By taking a piece of oily waste and wiping the face of the die as it is heating the different colors will show up clear. When the color denoting the temper required appears remove the die and allow it to cool off slowly.

Making the Blanking Punch.

Now for the blanking punch : Take the master blank or male templet ; remove the wire rod and mark the spot where it was attached, so as to know the back from the front of the blank. Then solder the blank, front up, to one end of the piece of tool steel which is to be used for the blanking punch. The punch can now be machined, either in the shaper or the milling machine, so that its entire length will be the shape of the blank, finishing it as close to the edge of the blank as possible. Now heat the sleel slightly and the blank will drop off. Clean the blank, lay it aside and proceed to fit the punch. If it is to punch very thin stock make it a tight fit within the die; if for heavy stock, a trifle loose. In order to make a punch a perfect fit for thin stock the edges of the cutting face should be beveled with a file. The punch should then be sheared through the die in the press in much the same manner as a broach is used, being careful to have it in perfect alignment with the die.

Before hardening the punch it is necessary to locate the holes for the pilot pins G. These pins are necessary in order to pro- duce pierced blanks that will be interchangeable. Take the master blank, enter it into the die from the back with the front up. It will fit the die tightly because of the shrinkage in harden- ing. Now enter the blanking punch from the top and locate the holes for the pilot pins through the holes in the blank with a centering drill. Drill the holes to size and harden and draw the punch to the temper desired, which should be in most cases a dark blue. In tempering the punch draw it from the back, allowing the temper to run out to the front; thus the back will be almost soft while the remainder will be as hard as required.

THE CONSTRUCTION AND USE OF BLANKING DIES. 25

The drawing of the punch so that the back will be soft is done to strengthen it and also to allow of upsetting it when locating it within the punch plate.

Locating the Blanking Punch in the Punch Plate.

To locate the punch in the punch plate, take the plate and clamp it true on the face of the die and transfer the outline of the blanking die to the face of the plate. Then work a hole of the shape of this outline through the plate, so that the punch can be entered face first through from the back. Then place both punch and plate under the ram of the press and set the punch dead square with the face of the pad and proceed to force it through, using the punch as a broach. It will be necessary to repeat this operation several times in order to get the punch through the plate, as the surplus stock curled up by the punch has to be removed. After having forced the punch into the pad until the face is through, force it back and out again. Now chamfer the edges of the hole at the back of the pad and force the punch in again, until the back is a shade above the plate, and upset or rivet as shown and finish it flat with the plate ; when this is done there will be no danger of the punch pulling out when in use.

Locating the Piercing Punches in the Punch Plate.

To locate the holes for the piercing punches, enter the blank- ing punch into the die until the faces of the punch plate and the die are within 3-16 inch of each other, with a pair of parallels between them. Then use the die as a jig and locate the holes for the piercing punches ; spot them deeply. With a. drill about two sizes smaller than the piercing dies drill entirely through the punch plate and then ream the holes to size. Use the die as a jig for all three operations.

For 'the two piercing punches use drill rod and upset the heads before hardening, as all small punches should be hardened for their entire length, as otherwise they would bend or break. If after hardening the punches are found to have sprung they must be carefully straightened before forcing them into the punch plate. Fasten the punch plate to the cast iron holder A, Avith four flat-head screws as shown.

26 DIES, THEIR CONSTRUCTION AND USE..

Finishing the Die.

All holes for screws and dowels in the stripper and gage plate should be transferred through the die. The holes for the two piercing punches in the stripper should be the same size as the dies, as by fitting tightly the punches are strengthened and supported while piercing the metal.

After the gage plates and stripper have been located and fastened upon the die as shown, with the stop pin located so that its locating face is the same distance from the edge of the blanking die as the width of surplus stock allowed between the blanks, the die is complete.

If the method of construction described and illustrated in the foregoing is properly carried out there will never be any possibility of failure in the accomplishment of the desired results.

Fundamental Points to be Remembered.

The practical points to be remembered when constructing a die of this type are as follows : Be sure to make an accurate pair of templets. Machine the punch holder and stripper plate accurately. Work the blank through the die, and use it for locating all the holes for the pilot pins and piercing punches. Finish the die before starting on any of the other parts. Trans- fer all holes in the punch plate through the die ; and, lastly, be sure to have the front of the master blank up during all opera- tions in which it is used. By keeping in mind these practical points a punch and die of this type can be constructed in which the alignment between all parts will be perfect.

Setting the Die and Using It.

To operate the die, drive the die proper into the die block or bolster, Fig. I, and then set it up in the press. The proper way to set a die of this kind is to first place the punch within the ram of the press and fasten it there. The punch should then be brought down until the faces are within ^ inch of the die face. Then, using the left hand through the press bolster, the die should be raised up until all punches have entered it. The punch should then be brought down about 5-16 inch and the die will rest squarely on the press bolster in perfect alignment with

THE CONSTRUCTION AND USE OF BLANKING DIES.

Fig. 1— Dish Pan

Fig. 8-Lard Pail

Figs. 5 and 6 Fig. 7— Coffee Boiler

Dipper Handles

Fig. ft— Dipper Bowl

Fig. 16— Scoop

Figs. 14 and 15— Tea and

Coffee Pot Spouts Fig 18_Dish pan

Handle

o

Fig. 10— Scoop Body

Fig'

Fig. 17— Scoop Band

Fig. 1&— Cup Handle

Fig, 20— Cup Handle

Figs. 21 and 22— Coffee Fig. 23— Saucepan

Boiler Lips Handle Fig. 24— Coffee Pot Handle

FIG. II. — DIAGRAMS OF BLANKS FROM CUTTING DIES.

28 DIES, THEIR CONSTRUCTION AND USE.

the punch. Now fasten the die to the press bolster and give it a rap with a hammer at either end to set it; then go ahead.

The stock to be punched should be entered beneath the stripper and pushed up against the stop pin. At the first stroke of the press the two holes are pierced and a scrap blank punched out. Now feed the stock forward until the back edge of the blanked hole rests against the stop pin, and at the next stroke as the punch descends the pilot pins in the blanking punch will enter the holes pierced at the first stroke and a blank will be produced which will be an exact duplicate of the master blank. The stock may then be fed along until the entire strip has been worked up.

A Plain Blanking Die.

When a plain blanking die is desired, to produce blanks of any circular or irregular shape such as the smaller ones shown in Fig. n, the description given herein for the construction of

PLAN OF PUNCH

PLAIN BLANKING PUNCH AND DIE

SECTION OF STOCK

SHOWING HOW TO SAVE METAL

FIG. 12.

FIG. 14.

the blanking die and punch portions of Figs. 6 to 8 should b( followed, and instead of making two templets make only one— the male.

As shown, plain blanking dies of the class shown in Figs

THE CONSTRUCTION AND USE OF BLANKING DIES.

12 and 15 are very produce blanks of shape from tin, iron, steel, aluminum, brass, copper, zinc, silver, paper, leather, cloth, etc. In Figs. 12 and 15, K is the punch holder or stem, I the punch plate, H the punch which is let into the punch plate and upset at the back, as shown. The punch plate is fastened to the holder face by four flat-head screws J J J J. The die A is worked out at B and finished to temp- let, C is the stop pin, F F the two gage plates, and G the stripper plate fastened and lo- cated by the four screws D and the two dowels E E. All plain blanking dies for punch- ing stock up to 3-16 inch thick should be constructed like this one.

simple in construction, any flat

They are used to

PLAN OF PUNCH

m ^_^_m

FRONT VIEW OF PUNCH, AND VERTICAL CROSS-SECTION OF DIE

FIG. 15.

Dies for Large Blanks.

Blanking or cutting dies for punching out large blanks from comparatively thin stock are made in almost every shape and size for cutting all kinds of metal. A number of different shapes and sizes are shown in Figs. 16 and 17, and a set of blanks produced in dies of this construction are shown in Fig. 18. This class of dies consists of an upper or "male" die, commonly called the punch, and a lower or "female" die, rightly called the die. As a rule the female die is hardened and tempered to the degree best suited for the stock to be punched, while the male die, or punch, is left soft, so that it can be upset at the cutting edges when worn, so that blanks may be produced which will be free from burrs and fins. The cutting edges of dies of this class are always sheared, the size of the blank and circumstances determining the amount of shear