1Pc 4-22mm HSS Step Drill Bit Straight Groove Spiral Groove Titanium Coated Wood Metal Hole Cutter 4241 High Speed Steel Core Drill Bit

1Pc 4-22mm HSS Step Drill Bit Straight Groove Spiral Groove Titanium Coated Wood Metal Hole Cutter 4241 High Speed Steel Core Drill Bit

Package Includes:1PC

Material: High Speed Steel

Supporting tools: Charging drill, Bench drill ,Pistol drill, Hand drill

Suitable Material:

Workpieces with general hardness, such as wood, plastic, PVC plate, iron plate, plate thickness within 3MM. Please note that stainless steel and spring steel are not applicable. Not for quenching. (Water injection cooling while working, it can effectively extend the service life of the drill bit, especially in the case of continuous drilling)

Attention:

Because of the outer diameter of each step of the step drill is gradually expanded,then the corresponding cutting resistance and linear velocity will also be gradually increased. Owing to the step drill is completely dependent on the inclined edge that is only with 1mm length,If the feed speed is too fast when drilling,it will be easily to be annealing caused by abrasion of the oblique edge. Please give a downward force when drilling, do not press down too hard to avoid the edge wearing.