Drill Bits for Metal Reviews and Charts

Drill Bits for Metal – Twist and Center Bits

 

Best Quality Drill Bits for Metal Review


Best Quality Drill Bits for Metal Review

Low-cost drill bits overview


Low Price Drill Bits for metal Comparison

Center Best Quality Drill Bits for Metal Review


Center bits

 


Coatings Best Quality Drill Bits for Metal Review

Coating Chart

Best Quality or Low Cost Drill Bits for Metal Review

Best Quality or Low Price - What to Choose

HHSS vs Titanium vs Cobalt Tools Comparison

HHSS vs Titanium vs Cobalt Tools Comparison

 

 Drill Bits General Characteristics

 

The twist drills are the mainly used type. It comprises a cutting point at the tip of a cylindrical shaft with helical flutes. Diameter varies from 0.002 to 3.5 in. Small ones are cheap to replace, for larger bits, special grinding tools are available. Even for industrial users, most holes are drilled with standard high-speed steel bits.

The most common twist drill bit for metal has a point angle of 118 degrees, also acceptable for use in plastic, wood and most other materials. A more aggressive angle (such as 90 degrees), is suited for very soft plastics and other materials; such a bit is generally self-starting and can cut very quickly. A shallower angle (twist drill bits for hardened steel) is suited for drilling tougher materials and requires a starter hole.

 

Drill Bits for Metal Construction

The main components of twist drills are shorn, body and drill point.

 

  1. Width of Land
  2. Rake or Helix Angle
  3. Width of land
  4. Body Clearance
  1. Flutes
  2. Land
  3. Leading Edge of the Land
  4. Heel
  5. Back Taper

Chart of Shapes Specification

Helix AngleHigh-hardness material Small Rake angle, Large Soft material (Aluminium, etc.)
Flute LengthIt is determined by the depth of the hole, bush length, etc.
Point AngleA standard point angle is 118° and be changed to suit different applications. Soft material – Small Point angle. Large – for harder material.
Diameter Back TaperTo reduce friction with the inside of the drilled hole, the portion of the flute from the tip to the shank is tapered slightly. It is set at a larger value for high-efficiency drills and the work material that allows drilled holes to be closed.