Drilling & welding

This grouping covers hole-making and joining. Drill bits are chosen by diameter, shank type and material, such as high-speed steel for metal or masonry-tipped bits for concrete. Welding rods need the electrode class and diameter matched to the base metal and the machine’s current range. For welding machines, note input phase, output amperage and duty cycle. Welding masks should state the shade or auto-darkening need; welding itself is work for trained operators.