DeWalt HSS E Cobalt Drill Bits 5.5 mm set of 10, high-speed steel cobalt

DeWalt HSS E Cobalt drill bits, 5.5 mm diameter, pack of 10 are high-speed steel bits alloyed with cobalt to deliver increased hardness and heat resistance. Designed for drilling into hard metals, these 5.5 mm bits maintain cutting performance under higher temperatures and prolonged use. The set of 10 provides multiple spares for workshop, construction, and maintenance applications and fits standard drill chucks for easy installation.

Advantages

The cobalt alloyed HSS construction increases wear resistance and edge retention compared with standard high-speed steel bits. The 5.5 mm diameter offers a common size for through-holes and pilot holes in metalworking. Ground tip geometry promotes accurate centring and reduces walking on hard surfaces. Supplied as a set of 10, the pack ensures consistent drilling performance and immediate replacement availability when bits wear or break.

Suitable for

• Drilling stainless steel sheets and plates
• Working with cast iron and heat-treated steels
• Workshop, fabrication and maintenance drilling tasks
• General metal pilot holes and through-holes

Key specifications

• Material: high-speed steel with cobalt alloy
• Diameter: 5.5 mm
• Quantity: pack of 10 drill bits
• Tip: ground geometry for accurate centring
• Compatibility: fits standard drill chucks
• Intended use: drilling hard metals including stainless steel, cast iron and heat-treated steels

How to use

Mark and clamp the workpiece securely before starting. Select a drill with a chuck that accepts the 5.5 mm shank and tighten the bit firmly in the chuck. For hard metals, start at a low speed to establish the hole and then apply steady feed with appropriate cutting lubricant to reduce heat and extend bit life. Use moderate pressure; excessive force may shorten bit life or cause breakage. Clear swarf frequently and allow the bit to cool during prolonged drilling.

Usage recommendations

Use cutting fluid when drilling stainless steel or other heat-resistant alloys, and pause periodically to clear chips and cool the bit. Replace bits when wear blunts the cutting edge to maintain hole accuracy and reduce workpiece damage.