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Drill bit sets come in various shapes and sizes but essentially they’re just used for making holes, so why the difference in price? There are hundreds of cheap quality bits that have flooded the market so here’s a guide to which characteristics to look so you can separate the good from the bad.

A brief history of twist drill bit sets

Invented in the 1860s by Steven A. Morse, the twist drill bit got its name from the original manufacturing methods. Grooves were cut into a round bar which were then twisted to create the spirals. Today modern techniques rotate the bar past a grinding wheel to create the flutes. Ground bits are much stronger and so this is one of the first properties to look for.

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A point to make

The point of standard drill bits is 118°. These are best for drilling materials such as wood, plastic and softer metals. With more expensive drill bits such as the M2 set you’ll see that the geometry is slightly different and they have a finer point. This enables the tip to cut into the material faster. For harder materials the bit will have a flatter point, normally 135°.

Prove your metal

Just as showing your mettle is about bravery and strength of character, the metal that goes into drill bits is an important characteristic to look for. Standard bits are typically made of High Speed Steel (HSS) which is hard and resistant to wear. HSS can also tolerate higher levels of heat. This is an essential feature to have as the friction generated when drilling is obviously considerable. Drill bits made of inferior quality metals will quickly lose their edge as they get hot. In the end you’ll have to replace them more frequently and ultimately this results in poorer quality holes. The M2 steel in the Axminster M2 drill bit set is of a better quality to standard HSS and this gives it a higher wear resistance.

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Drill bit anatomy

Looking at the anatomy of your drill bit sets is another indication of the quality. Cheaper drill bits will have more of a land. The web on a bit is the actual thickness on the drill point and this thickness increases as the bit is sharpened.

How our drill bit sets compare

13 Piece High Speed Steel Ground Drill Bit Set 19 Piece High Speed Steel Ground Drill Bit Set Axminster 19 Piece Metric M2 Drill Bit Set
Description To the point – A solid basic set for when you just need simplicity and speed. The SAS of HSS – Like a crack military unit these are tough, durable and precise. Drill Masters – Superbly refined from high quality steel, these will competently cope with harder materials with excellent chip clearance and a quality cut.
Sizes 1.5mm to 6.5mm in 0.5mm increments, plus 3.2 and 4.8mm 1-10mm in 0.5mm increments 1-10mm in 0.5mm increments
Usage Wood, metal and plastics Wood, metal and plastics Different materials including hardened steels to HRC-30
Made From Ground High Speed steel Ground High Speed steel Swedish M2 grade steel
Supplied In Plastic case Good quality, reusable metal case Robust plastic case