HSS-G centre drill DIN 333 A ø4.0 mm

By centring first, you prevent a twist drill from wandering across the surface. The drill then follows the hole you made and starts exactly at the spot you marked. This is especially useful on round or smooth workpieces, where an ordinary drill quickly slips off centre.

What does DIN 333-A mean?

DIN 333 is the standard for centre drills and, among other things, describes the shape of the centre hole. Form A is the version with a standard conical point without a protective countersink. The hole it makes is intended to support a live or fixed centre of a lathe, or as a starting point for a subsequent operation.

What work is an HSS centre drill suitable for?

HSS is a commonly used material for drilling in metal. You use this drill, for example, when turning shafts, creating a starter hole for a larger twist drill, or marking drill positions in sheet metal and profiles. For harder or tougher materials, choose a lower speed and use cutting oil or coolant, so the point stays sharp longer.

What should you consider when choosing a size?

The diameter of 4.0 mm suits workpieces of limited size. Look at the diameter of the workpiece and at the drill or tool you plan to use afterwards. A centre drill that is too small provides little support for a larger drill, one that is too large removes unnecessary material. Also check that your drill chuck or collet grips the shank properly.

Frequently asked questions

What is the difference between a centre drill and a regular twist drill?

A centre drill is short and rigid and makes a conical hole to centre the workpiece or guide a drill. A twist drill is longer and intended to drill the actual hole.

Can I also drill wood or plastic with this drill?

This drill is intended for pre-drilling and centring metal. For other materials, it is better to choose tools designed specifically for them.

How do I prevent the point from breaking off?

Clamp the workpiece firmly, use a moderate speed and apply even pressure. A centre drill is short and rigid, but the point remains fragile under lateral load.