Drilling Techniques
If you ever need to drill a technique, this shows you how.
Wood
Many bit types will drill wood successfully. The fastest lowest energy use bits for wood are steep angled twist drills. Standard universal twist drills have poor angles for woodwork, they will cut but make an unnecessarily hard job of it.
Lip & spur bits, aka brad point or dowel bits, perform rather better in wood than standard HSS twist drills.
See Drill Bits for the many wood cutting bit types.
Mild Steel
Standard HSS bits
Speed:
Pressure:
Drill a small centre hole, then enlarge with a bigger bit. The reason for this is that standard twist drills have a small relatively blunt section in the centre.
Stainless Steel
HSS bits are not very successful on ss. Cobalt steel bits will drill ss, but won't last long.
See Superhard Drills for other bit options
Aluminium
Aluminium bonds to HSS bits. This problem can be reduced with lubricant.
Titanium coated bits perform much better than HSS with aluminium.
Cast Iron
Glass & Tiles
Glass & tile drill
Masonry & Stone
TCT masonry bit with hammer action. Failure to use hammer action causes very short bit life.
Reinforced Concrete
Masonry bits will not drill through steel reinforcement, and HSS bits that drill steel will not drill concrete. The solution is a bit designed for both, such as Irwin cordless, Bosch multi-construction, etc.
Butter & Soft Cheeses
3 for £1 long drill bits are suited to these materials.
Plastics
Twist drills, any of HSS, titanium coated, or steep angle bits.