Page:Popular Science Monthly Volume 92.djvu/469

 Tricks of the Trade

Attachments for Using a Vise as a Punch Press

A way to use an ordinary vise for making light duplicate parts from thin sheet metal

��SMALL duplicate articles are ordina- rily made in punch presses, but for the home workshop or a small job- bing shop such a press is too expensive. Ordinary punching or forming in 3/16-in. sheet metal may be handled in a vise with the power of the screw, by attaching the

��5PR1NG DIE

STRIPPER PLATE GUIDE PIN

DRIVING PLATE

���PUNCH

FIG.l.

ASSEMBLY (5IDE ELEVATION)

��The two parts attached to the vise jaws for holding the die and punch in Une

specially constructed parts to the jaws as shown in the illustrations. With this device many small things can be turned out as rapidly and accurately as if made in a regular die press. The parts assem- bled are shown in Fig. 1.

The base. Fig. 2, is attached to the fixed jaw of the vise by the upper and lower clips A and B, Fig. 1. These clips keep the base from pulling away from the vise jaw when the punch is pulled from the die. These clips are attached to the vise jaw with round head K-in. machine screws.

��In Fig. 2 is shown four K-in. tapped holes for guide pins, Fig. 3, two of which are plainly shown in place in Fig. 1. To assist in returning the punch after the operation, four helical springs, shown in Fig. 4, are slipped over the four pins.

The driving plate. Fig. 5, in general dimensions is a counterpart of the base. There are four holes drilled and reamed carefully to size for the ends of the guide pins. It is very necessary to make the base and drive plate accurately so that the parts will come together in line.

The stripper plate, Fig. 6, consists of two parts, the plate and its base block. The base block is merely a piece of metal cut to the size given, which supports the stripper far enough from the face of the die to permit the stock to be inserted for piercing.

The dimensions of the clips for holding the base and driving plate are given in the details of Fig. 5. Three punches and dies are shown in Fig. 8, 9 and 10, the simplest form being shown in Fig. 8. For ordinary punching, the punch face or end must be flat and have a clearance, as shown. Clearance is a slight taper from the cutting edge to the tank. The proper amount of this taper is 1/64 in. to each 1 in. in length. At the junction of the punch and the shank a heavy fillet should be formed as shown. Never make a punch with a square shoulder at this point.

��5TAP- ^' COUNTERBORE

��■^ REAM=PU5H-FiT f OR

��WIND ON -g MANDRE.I,

��hil \\hiH l-? + zH ^i'TAPFOR f-|"H GUIDE PiNS. l-J-

J_l \ \ 'y^i STRIPPER 1 y'x^ I,

��rff:

��: DRILL-

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��1,Tj- fCOUNTERBORE, p^^

��MACM, ST. ■f ALL OVER

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��H §"REAM Vl-

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PUNCH RETURN 5PRING

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I3THD5'PER1N.-US 5

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���FIG. 5.

��GUIDE P1N5. FIG. 3.

��Dimensions of the various parts used in constructing the holders for the dies and the punches to attach to the jaws of an ordinary bench vise for making small duplicate parts

453

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