33/64" X 3/16" Pilot Hole HSS Straight Shank Counterbore BoltsandNuts.com Tap Drill Size #28

Tap Drill Size #28

Part Number: 87C350HSBA325G/PT

Reach around obstructions and access fasteners at an angle with the universal joint

Screw machine drills (also know as stub or stubby drills) are manufactured to National Aerospace Standard 907

Length 2-5/8"

33/64" X 3/16" Pilot Hole HSS Straight Shank Counterbore BoltsandNuts.com Tap Drill Size #28Product Description Counterboring is the enlargement of a portion of a hole that has previously been formed. If the counterbored portion is shallow (1 8" or less), the operations is usually known as spot facing; for example, a flat seat for a bolt head or nut. If, on the other hand, the hole is enlarged to a considerable depth, it is designated as counterboring. These counterbores are made of two piece construction, having an integral shank and