Availability: 7 in stock
Viking 93840 Magnum Super Prem. Set Jobber Length Black & Gold 115pc
Magnum Super Premium drills substantially outperform cobalt drills in work hardening Stainless Steel applications. This performance advantage is the result of construction differences between the two types of drills. Cobalt drills, manufactured to Type J NAS 907 specs, have a very thick web. This web is necessary to limit breakage of the brittle cobalt steel. Magnum drills are made of special hi-moly tool steel, which is much tougher than cobalt steel. Magnum drills with their thin web will penetrate the work hardening stainless fast enough to continually cut beneath the chip which is hardening from deformation. This means the drill is cutting softer steel.