标准麻花钻的钻心比较薄,采用宽钻心后,钻头则度可增大,能钻得更直、更深,并能获得更准确的钻削直径,还可使进给量提高20％左右,是钻削坚硬材料的理想钻具.但要有效地使用它,需减小宽钻心钻头钻削时的进给压力,一般是将钻尖(横刃)磨薄或对开,这就需要进行二次磨削加工,以及进行此项加工的附加设备。如用手工磨薄钻尖,不易对称准确,就会导致定心不良,孔径过大或钻头迅速磨损。美国Bickford公司的新型宽钻心钻头的钻尖采用螺旋面作为后角的成形面,并修磨成所谓Bickford几何形状,是不需要二次磨削加工的。螺旋面钻头顶部成S形横刃,钻削时会自动定心, The standard twist drills are thinner. With wide drills, the drill bit can be enlarged to drill more straight and deeper, with a more accurate drilling diameter and a feed increase of about 20%. Ideal tool for drilling hard materials, but to use it effectively, it is necessary to reduce the feed pressure during drilling of a wide-bored drill bit, usually by thinning or separating the drill bit (chisel edge) Secondary grinding, as well as the processing of additional equipment. Such as hand-sharpened thin drill tip, difficult to accurately symmetry, it will lead to poor centering, aperture is too large or drill quickly wear. Bickford company’s new wide drill bit drill tip with helical surface as a relief forming surface, and grinding into the so-called Bickford geometry, does not require secondary grinding. Spiral top of the drill into a S-shaped chisel, drilling will be automatically centering,