Kierrep pora KWB 421600 13 kpl

The KWB 421600 twist drill bit set contains 13 precision ground, right-hand rotation drill bits made from a 5% cobalt alloy. Finished in a bronze colour and supplied in a hanging box, the set covers sizes from 1.5 to 6.5 mm plus 3.3 mm and 4.2 mm. Each bit has a 135° tip angle with cross-ground geometry to DIN 1412 C and a cylindrical shank; they are self-centering and manufactured to industrial quality standards for demanding drilling tasks.

Advantages

These KWB cobalt twist drills combine wear resistance and heat resistance for improved performance when working with hard materials. The 135° tip and cross-ground cutting edges provide accurate centring and clean hole finish, while the precision ground flutes and alloy composition help maintain cutting geometry under high temperatures.

Suitable for

Key specifications

How to use

Mark and centre the drilling position, clamp the workpiece securely and select the appropriate drill size from the set. Use suitable cutting speed and coolant or cutting fluid when drilling hard or stainless steels. Apply steady feed pressure without forcing; withdraw occasionally to clear chips. Ensure the drill is held concentrically in the chuck to maintain accuracy.

Recommendations

For best results on stainless and alloyed steels, use reduced cutting speeds, appropriate coolant, and progressive peck drilling where necessary to avoid overheating and extend tool life.