Punch and die do the job9853661
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PUNCH AND DIE Work
CONTENTS - Principles of Punch and Die Get the job done - Suggestions to the Making and Usage of Dies - Samples of Dies and Punches
MACHINERY'S REFERENCE Collection The industrial Push, The big apple, 1911
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Rules OF PUNCH AND DIE Work
Beneath the head of punch and die get the job done is normally provided each of the various resources employed in blanking items from commercial stock; bending stock to form; drawing out posts from sheet stock; and all of the different operations executed with punching, drawing and forming presses. The commonest types of tools for being regarded will be the dies utilized for blanking posts from sheet stock, named blanking dies.
Blanking Dies
A set of blanking dies contains a male die, or punch, because it Is generally termed, plus a woman die, or die block. These phrases are generally abbreviated and the established is known as a punch and die. Blanking dies are usually regarded as belonging to 1 of a few classes: Very first, simple (or easy) dies; 2nd, gang dies; and 3rd, compound dies.
When punches and dies are utilised in a very punch-press, and are to constitute an element on the regular equipment from the store, they can be held in ideal permanent fixtures. Dies are held in place to the bed of your press by means of a "holdfast," the title of which differs in several stores. A few of the extra common names are chair, chuck, bolster, and die holder. Dies substantial ample to warrant it are clamped for the bed in the push, hence doing away while using the requirement for holders. Dies are fastened in place during the die holder by many techniques, the most typical of which happens to be through screws, as proven in Fig. one, during which a may be the die and & the holder. Having screws on both sides, it can be an easy matter to adjust the die, loosening the screws on 1 side, and forcing the die over by those within the opposite side.
When the die is small, it is frequently held inside a shoe, as proven In Fig. 2. The manner of fastening the die within the shoe usually depends to the designer. In some shops the shoe is dove-tailed as demonstrated, the angle being from 10 degrees to 15 degrees less than a right angle; the slot is made somewhat tapering. The die is given a corresponding taper and angle on its sides, and, to fasten it in placement, it can be driven securely in position. The amount of taper given the slot within the shoe must not be great, or the die will jar loose when in use. A taper of one-half inch per foot of length answers nicely. In other shops the shoe is made with a groove, as described above, only it truly is from 1/4 to 3/8 inch wider than the dies, which are held in position through a taper key or wedge, as demonstrated in Fig. 3. When making this form it truly is necessary to make the dies of equal width on their ends. This method does not require so great a degree of accuracy when machining the die block.
A third method consists in generating a shoe having the back from the slot planed at the angle mentioned, while the front wall is made square along with the bottom, the die being held with setscrews, as revealed in Fig. 4. If this form is utilised, care must be exercised when laying out the screw holes, so that they do not come in line while using the screws in the bolster when the shoe is in its proper spot; and, again, the screws must not push on any portion on the die immediately in line along with the opening, or it will be closed somewhat when pressure is applied for the screws. Fig. 4 shows the screws pressing on the solid portion in the die.
Dies which are fastened in bolsters without using a shoe must have their sides machined at an angle, as in Fig. one, to prevent them lifting from the strain incident to removing the punch when it has pierced the stock. The angle should be from 10 degrees to 15 degrees, some mechanics claiming best results with 20 degrees. The latter, however, seems greater than there is any necessity for on ordinary operate. Kind of Steel Used for Die Perform
For most do the job the stock utilised in creating punches and dies should be a good quality of tool steel. A die that has cost from 5 dollars to 100 dollars for labor is as liable to crack when hardening as though the same steel had been made into any other form of tool; and in fact its condition and irregular thickness of stock at several points, together with numerous sharp corners that are liable to be present, make a tool that requires extreme care in handling when hardening. A good grade of tool steel, no cost from harmful impurities, is less liable to crack then an inferior grade, and the slight difference in cost is offset many times by the cost of labor in the die construction. This does not necessarily mean that a high-priced steel must be used for this class of operate; simply a good quality of steel, low in percentage of those impurities which cause trouble when the steel is hardened. When we speak of good, reliable steels, we do not necessarily mean high-priced steel.
If best results are desired when hardening, the steel should be annealed after the outer surface from the piece has been removed and also the opening blocked out somewhere near to shape.
In all shop operations true economy should always be practiced, and many times this may be done by a saving of tool steel. If a die is like Fig. 5, a saving may be effected by generating the body of cast iron and inserting bushings of tool steel; and if we wish at any time to make a new die, we simply make the bushings, and if ordinary care is taken, the holes will be concentric and consequently the proper distance apart, so there will be no necessity of altering the location with the punches, as might be the case if a die made of the solid piece was hardened.
General Rules of Die Earning
When a number of dies are to become made to fit the same holder, they may be planed to size in the bar and then cut apart by means of the cold-sawing machine. It will be necessary to plane again the side of dies that must fit a shoe with the style revealed in Pig. 2, as one end must be wider than the other. This may be effected very readily by having a strip of cast iron planed to the proper taper to area the die on when planing or milling. The face from the die must be smooth in order that the outline traced on it may closely correspond towards the templet. If the surface is a succession of ridges, the scriber will not closely follow the edges of the pattern, and also the figure traced will be larger than desired. After the face has been made smooth by planing, grinding or filing, the surface may be coated with blue vitriol solution, or it may be heated until it assumes a distinct straw or blue color, and the outline on the piece to become punched laid out.
If the die is what is known as a solid die, that is, made from a single piece of stock, it may be laid off and prick-punched as in Fig. 6, after which holes may be drilled, leaving the face of the die as in Fig. 7, after which the core may be removed. When drilling to the opening, initially drill any portions which are to generally be left circular or semi-circular in condition. These are then reamed from the opposite side with a taper reamer that will give the desired amount of clearance. When drilling to remove the core mentioned, some tool-makers use drills of sizes that break into the next hole. After drilling all way round, the core drops out of its own accord. If this method is adopted, best results follow the use of the straight-fluted drill. Fig. 9. Others drill with drills of your size from the pilot of the counterbore, and after drilling each of the holes, the counterbore is run through. Of course, it is actually understood that in laying off for the holes, they're located so that the counterbore breaks into the next hole. A 3rd method is made of laying off and drilling holes so that there is a little stock between the holes after drilling, which can be broken out by the use of a drift driven in from each side until the cuts meet. In this way the stock is cut away and also the core removed.
After taking out the core, the die may be placed inside a die milling machine, or a die sinking machine, and by the utilization of a tapered milling cutter the stock may be removed as well as desired angle of clearance given the walls in the hole. The angle of clearance necessary for best results cannot be arbitrarily stated, but varies according to your character of your operate being done with all the die. Within the absence of either of the milling machines mentioned, a universal or a hand miller may be made use of. There are a variety of slotting devices which may be attached to universal milling machines which are used advantageously on work of this character. During the past few years numerous vertical filing machines have been placed on the market which are recommended highly for the purpose of working the openings of dies to form. If a die milling machine. Fig. 8, is made use of, the form of taper milling cutter revealed in Fig. 10 is employed. As the milling cutter is driven by a spindle beneath the die, the cutting portion extending up through the opening, with the face with the die uppermost, the small part of the cutting portion should be at the end in the cutter. If a die-sinking machine, Fig. 12, is used, a cutter like Fig. 11 is employed. After working the opening to shape and size as nearly as possible using the milling cutter, it may be finished by filing stamping parts.
