The gap of the punch die, according to the different materials, different thickness, the gap value is also different: for example, mild steel and brass, material thickness 0.4~1.2mm, the gap value is 7%~12% of the thickness (bilateral), and the same thickness, the gap value of hard steel is 10%~17% of the thickness (bilateral); The material thickness is 1.2~2.5mm, the clearance value is 9%~12% of the thickness (bilateral), and the clearance value of hard steel is 18%~25% (bilateral); The material thickness is 2.5~4mm, the clearance value is 12%~16% of the thickness (bilateral), and the clearance value of hard steel is 15%~28% (bilateral); The material thickness is 4~6mm, and the gap value is 15%~18% of the thickness (bilateral). The gap value of hard steel is 27%~29% (bilateral).
When you cut a cold die, you cut a punch and a die on a piece of template. You can drill a line hole in the concave hole within 5mm close to the concave hole. When cutting, ensure the size of the concave hole and cut out a straight, non-oblique concave hole. The material in the middle of the cut mold hole can be used as a punch. However, this cutting method can only be used for molds with large gaps. If the gap between the punch and the die is required to be small, it is necessary to use the method of cutting the die out of the slope, so that the punch material cut is larger than the hole of the concave die. Then the grinding machine is used to grind the punch material to the suitable size.
Punch; Where the gap of the die is placed depends on whether you are processing a punching die or a blanking die. If it is a punching die, the punch takes the standard size, and the gap is placed on the concave die, that is, the size of the concave die = the standard size + the gap value of the punch and the concave die; If it is a blanking die, the concave die takes the standard size, and the gap is placed on the punch, that is, the size of the punch = standard size - the gap value of the punch and the concave die.