Tips and tricks
Practical die making
PRACTICAL DIE MAKING
A collection from the latest information on dies and die making.
BY FRED H. COLVIN
McGRAW-HILL BOOK COMPANY, NEW YORK, 1916
DOWNLOAD FREE BOOK: Practical die making
INTRODUCTION
The best information in any line of work does not come from the work of any individual but from the combined experience of many. Each contributes his share and the combination gives us a far wider range of information than we could secure in any other way. So in compiling this book it has been the aim to secure facts and examples from many sources in order that every reader may find some of the work just suited to his needs. No originality is claimed and full credit is given so far as possible in the list of authorities in another part of the book.
CONTENTS
- Bending and Forming Dies
- Punching, Shearing and Blanking
- Drawing Sheet Metal into Various Shapes
- Press Tools Used in Clock Manufacture
- Data and Suggestions on the Making of Dies
CHAPTER III - DRAWING SHEET METAL INTO VARIOUS SHAPES
This is another department of press work which has made great advances in a comparatively short time. Cold sheets are now drawn and shaped almost at will, into forms which was considered impossible but a few years ago, the marvel being that cold metal will withstand such stresses without tearing. This is allowing the use of sheet metal for many parts which were formerly made of castings and machined in various ways. Examples of this class of work will be shown in this section.
Drawing a Difficult Shell in a Single-acting Press. - This shows a drawing die, with some novel features. Fig. 96 shows the five operations required on a single-acting press to produce the finished shell shown in Fig. 97.
Operation 1 shows the blanking and drawing die which knocks the shells out with a kicker that passes through the back of the press and rests on the top of the stripper. The cross-section and the punch in position shows the little knock-off pin which disappears during the operation and which pushes the shell away from the stripper to which it is held by suction. An enlarged view of the pin is shown at A.
The punch has a thread cut on it to screw into a plate % in. thick. This plate bolts to the ram of the press and takes all the pull and strain from the setscrew. The blank from this die is shown at C.
The second-operation die is shown in part cross-section, and is held in a cast-iron shoe, not shown. A cap bored to take the shell C, is threaded and screwed into the shoe. It locates the die and holds it. It bears on the 45-degree angle X of the die. The draw from this operation is shown at D. This punch also screws into the same plate as the previous punch.
In operation 3 the punch only is partly shown, but it and the die are made in the same manner as the previous punch. The punch used in this operation is chamfered to give the shell a start in the die for the fourth operation. The shell from the third operation is shown at E, and F is a bottom view of it. The fourth operation produces the shell marked G, and H is a bottom view of it. The reason of the chamfer is plain as the corners on the shell are required to come as sharp as possible, and if this had not been done in the third operation, the fourth would have made a bad mark about y± in. up on the shell, which would have required a lot of polishing to get out.
The fifth and final operation is now to be done. The punch is made to the exact size and shape (shown reduced in size in operation 5, Fig. 96). The die is shown large in Fig. 97 in order to make it clear.
DOWNLOAD FREE BOOK: Practical die making
Drawing a Difficult Shell in a Single-acting Press. - This shows a drawing die, with some novel features. Fig. 96 shows the five operations required on a single-acting press to produce the finished shell shown in Fig. 97.
Operation 1 shows the blanking and drawing die which knocks the shells out with a kicker that passes through the back of the press and rests on the top of the stripper. The cross-section and the punch in position shows the little knock-off pin which disappears during the operation and which pushes the shell away from the stripper to which it is held by suction. An enlarged view of the pin is shown at A.
The punch has a thread cut on it to screw into a plate % in. thick. This plate bolts to the ram of the press and takes all the pull and strain from the setscrew. The blank from this die is shown at C.
The second-operation die is shown in part cross-section, and is held in a cast-iron shoe, not shown. A cap bored to take the shell C, is threaded and screwed into the shoe. It locates the die and holds it. It bears on the 45-degree angle X of the die. The draw from this operation is shown at D. This punch also screws into the same plate as the previous punch.
In operation 3 the punch only is partly shown, but it and the die are made in the same manner as the previous punch. The punch used in this operation is chamfered to give the shell a start in the die for the fourth operation. The shell from the third operation is shown at E, and F is a bottom view of it. The fourth operation produces the shell marked G, and H is a bottom view of it. The reason of the chamfer is plain as the corners on the shell are required to come as sharp as possible, and if this had not been done in the third operation, the fourth would have made a bad mark about y± in. up on the shell, which would have required a lot of polishing to get out.
The fifth and final operation is now to be done. The punch is made to the exact size and shape (shown reduced in size in operation 5, Fig. 96). The die is shown large in Fig. 97 in order to make it clear.
DOWNLOAD FREE BOOK: Practical die making
Free books category: