The practical tool-maker and designer: a treatise upon the designing of tools and fixtures for machine tools and metal working machinery by Wilson Herbert S

Author:Wilson, Herbert S
Language: eng
Format: epub
Tags: Tools, Machine-tools
Publisher: Philadelphia, H. C. Baird & Co.; London, S. Low, Marston & Co., limited
Published: 1898-03-25T05:00:00+00:00

Fig. 119.

^1

i|

To face page 1^.

In swaging ferrules into special shapes, such as oval, hexagon, square, etc., the last break down should approximate the size and shape of the finished tools. Previous to the last break down the work may bo best brought forward in the round.

To give ferrules special shapes for a part of their length, it is only necessary to carry out the ideas given under the head of shouldering, substituting special shaped punches and dies for the plain ones described. Large quantities of such work may be produced rapidly and cheaply by means of the water die as elsewhere described. Work may be flanged or widened out at the open end in two ways: Either by shoulder drawing, and afterwards trimming out the part wanted, or by flanging or spreading • out the open end of a straight femile. When the work is done by shouldering, the stock will all be of one gauge, but where it is produced by flanging or stretching, that part of the stock where the flange is turned over will be thinner than the balance of the work. Narrow flanges will work all right if spread out, but wide flanges must be broken down to shape by several operations as in making shouldered work. In trimming flanged work it is best to make use of a cutting die, punching or trimming the flange, and forcing the finished piece entirely through the die at each stroke. Do not forget the guide or finder pin on the end of the punch.

Irregular work, such as lamp burner tops, oil can bodies, and all similar shaped pieces, are best made in

two or three operations, using a cup having as near the general outlines of the finished piece as can be made in the double acting press. There are some kinds of such work which can be made directly by the cupping press, but many shapes will occur w^hich are either too deep or have too many angles to make in a single operation, without bad crimps showing in the W'ork. From the illustration, Fig. 123, it will be seen that the angle at A^-could not be formed except in a die which bottomed and was provided with a knock out. The finishing of such pieces properly belongs under the class of tapered work, and with the exception of the shape of the tools is usually made in the same manner.

Trimming.

There are three ways of trimming, varying with the nature of the work. Thick work is usually best sawed. Small work will trim best with a cutting tool similar to a cut-off tool in the lathe, the work being held on a revolving mandrel by means of a tail spindle made to revolve at the same rate of speed. Such a machine is called a trimming lathe.

For ferrules which are not too thick or too small in diameter, the shearing tools showm in Fig. 124 will give the hitrhest results attainable in hand work. Everv-thing about these tools should run perfectly true, and the sj)ecd for brass work should be about two thousand per minute.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.