Dormer Drill Bit HSS Set 15Pcs. No.20 1/16-1/2″

Comprehensive Size Range The set includes 15 bits starting from the delicate 1/16″ for pilot holes and micro-assembly, up to 1/2″ for heavy-duty structural work. It includes the “in-between” sizes like 9/32″ and 13/32″ that are often missing from cheaper kits but essential for professional mechanics.

TiN-Tip Performance (A002 Series) The gold Titanium Nitride coating on the working end of the bits acts as a thermal shield. This allows for faster drilling speeds and significantly reduces the wear on the cutting edge, lasting up to 3 times longer than standard black oxide bits.

Self-Centering Split Point Bits from 1/8″ and above feature a 118° split point. This geometry allows the bit to “bite” the material instantly without the bit “walking” or skating across the surface. It eliminates the need for a center punch in most applications.

Superior Swarf Evacuation Each bit is ground with precision flutes that lift metal chips (swarf) away from the cutting face. This reduces the risk of the bit seizing in the hole and prevents the “packing” of material that causes heat-related snapping.

Steam-Tempered Finish The body of the bit is steam-tempered, creating a blue/black porous surface. This helps “wick” and retain cutting lubricants, ensuring the tool stays cool even during deep-hole drilling in tough alloys.