Surely many were faced with a situation where a self-tapping screw or screw is not screwed exactly in the center of the hole, but is shifted to the side, its cap is fixed in a "sweat" at an angle, which sometimes affects not only the appearance of the structure, but also its functioning (drawer slide) , eg). Unscrewing the fastener with the aim of re-screwing it often leads to destruction of the material structure. Once and for all, self-centering drills can help solve this problem. They are made of high speed steel (HSS), the body is made of galvanized brass. The presence of a hexagonal shank (1/4 "diameter) allows them to be used in bit holders, due to which the process of drilling a centering hole and then replacing the bit to screw a screw or a self-tapping screw into it is significantly accelerated. Drills are suitable for working with relatively soft materials, starting from wood and ending with plastic.In case of wear, the drills can be removed from the case and replaced with similar ones, since you can easily find them on Ali. 7 drills are included in the package of delivery, brands are present on their bodies size adjustment.
The principle of operation of such a drill is as follows: its “nose” is movable, fixed with a spring, when the drill is installed in the hole, the nose centers it, and after pressing the drill, the “nose” hides in the wider part of the drill, releasing its cutting part, which makes a hole.
The dimensions of the drills and their mounting hardware are shown below (drill diameter; body length; diameters of suitable hardware):
• 5/64 "(~ 1.98 mm); 84.5 mm; 2.2 mm - 2.8 mm;
• 7/64 "(~ 2.78 mm); 87 mm; 3 mm - 3.5 mm;
• 9/64 "(~ 3.57 mm); 94 mm; 4 mm - 4.5 mm;
• 11/64 "(~ 4.37 mm); 96.5 mm; 5 mm - 5.5 mm;
• 1/5 "(~ 5 mm); 106 mm; 5.5 mm - 6 mm;
• 13/64 "(~ 5.16 mm); 106 mm; 6 mm - 6.5 mm;
• 1/4 "(~ 6.35 mm); 110 mm; 7 mm - 7.5 mm.
Cost: ~ 649