This section is from the book "Machines And Tools Employed In The Working Of Sheet Metals", by R. B. Hodgson. Also available from Amazon: Machines and tools employed in the working of sheet metals.
The old adage-an incompetent workman finds fault with his tools-is as true in press work as in any other industrial department.
No matter how well designed and equipped a works may be, unless the shops are under good management, assisted by competent workmen, the result will be unsatisfactory. It would be beyond the province of these articles to give all the details necessary to explain how every machine should have its varied tools set for successful working. We will therefore briefly draw attention to some few points of general application concerning the tools in this important section of machine working-points that are to some extent overlooked or considered to be of little import, although they govern the quantity and quality of the production, besides affecting both the life of the machine and its tools, in addition to frequently resulting in power being lost or wasted in unproductive work.
Assuming that a first-class machine is supplied with thoroughly accurate tools, the next question is, naturally, the setting of these tools so as to enable the operator to produce good work quickly from the machine. This would in some instances be a simple matter which a careful machine attendant could manage. In other instances the tools may be of such a complicated nature, that a considerable amount of ability and experience may be required to set the tools. A few examples will demonstrate that this is so. In the case of cut-tach and tingle making, an experienced machine minder will have charge of from six to twelve machines; he will both make, grind, and set the tools, but will have female operators to put the strip-iron into the machine, and attend its working. Wire-tach, rivet, panel-pin, wire-nail, staple, and split cotters is a class of work also requiring a skilled mechanic as chief minder, to make and set all tools, the wiring of the machine from the swift being carried out by female or male attendants, according to the size of the work-i.e., the weight of the coil of wire from which the nails are made. Thus in the case of nail machinery the tool-maker is held responsible for the correct setting of his own tools, besides the supervision of the machinery when in motion.
As another example, we may consider metal-stamping, drop-forging, and similar work. The stamping or forging dies will be made in a tool-room, thence passed into the hands of an experienced stamper, capable of setting his own tools in the stamp, though he be neither a tool-maker nor mechanic. In other instances the stampers, both male and female, may not be capable of setting tools, but merely proficient in placing the metal between the die? and working the stamp. Regarding press tool-setting, it may be truly said that, as a general rule, in small workshops this question is considered to be of minor importance, although a great waste of time and material is caused, due alone to imperfect tool-setting.
An instance came under the authors notice. In a factory where hundreds of machines were in use the more important tools and machines were made in one large fitting and tool-making shop in a central part of the works, thence supplied to the various work-rooms, each under the supervison of a tool-setter having charge of a number of machines and presses, the operators being pieceworkers. It was noticed that in a certain work-room an unusually heavy demand for tool renewals was experienced. The machines which had been condemned by the tool-setter were replaced with new and first-class machines; but neither the quantity nor quality of the output improved, nor the demand for tools reduced with the new machines. A competent machine-tool fitter was despatched to carefully examine the machines and investigate matters generally, when it was found that the press-rams-which had been properly adjusted in the machine-tool shop-had been re-adjusted by the tool-setter. The slides and rams of the machines were found to have been tightened, requiring considerably more power to drive the machines, besides galling the slides, rams, and guide strips-in fact so much so that re-planing was necessary. The cause of all this trouble was traced to defective tool-setting, and the tool-setter had gripped up the rams, thinking thereby to prevent the tools kicking. In the other workrooms, where the adjustments of the machines had not been tampered with, no trouble was experienced.
If the tool-setter finds a slide or ram working slack, he should immediately draw the attention of the machine-tool fitter to the defect. If a ram is to work properly, it requires careful adjusting, so that it may work up and down its stroke quite freely, yet have no play or be likely to kick when working the tools.
Any slide or ram is difficult to set accurately, and the most troublesome to set is the fly-press ram of square pattern, as these may be adjusted so tightly that they can be scarcely moved by the screw, yet they will kick sufficiently to ruin a pair of cutting-out, blanking, or piercing tools at the first blow.
Although it has been mentioned as being advisable, if possible, to have someone to do the tool-setting who has had some training in tool-making, there are instances known where workmen, without any previous knowledge of working machine tools of any kind, have been trained to set tools in the press, and have become quite expert and valuable tool-setters.
The question of tool-setting is an imporkant one, and should always be kept in view when tools are being designed. It is, however, too often the case that no thought whatever is given to this question; consequently a set of tools-say, for example, a punch and die-are made before any thought is given to either the tool-setting or how the metal blanks are to be stripped from the punch. The result is that probably an unsuitable stripper is used, and a rough method of setting adopted. The method of stripping the scrap metal in press work plays a very important part upon the successful action, as well as upon the life, of the tools; particularly is this so in the case of small delicate press-tools, where a crude stripper arrangement will frequently make bad work, in addition to damaging or breaking the tools.
 
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