Also called wafer head self drilling screw, is an extra wide head twinfast thread self drilling point screws with a wide integrally formed round washer head and a low rounded top that is around 75% width of the washer diameter, generally with a philips drive. Common used to attach wire and metal lathe to a metal studs of a thickness between 12-20 gauge. The large washer head offers low clearance and extra large bearing surface, the usual drive speed for installation is around 2500 RPM. Screws to be quenched in liquid and tempered by reheating. Surface hardness at Rockwell C 50-56, core hardness C32-40.
Size: thread #6 and #8 (3.5mm or 4.2mm), length from 1/2 to 3 inch (13mm to 76mm)
Material: C1018, C1022 hardend Steel
Surface treatment: blue/white zinc, yellow zinc, copper, bronze, brown, brass coating
Pls click below links for standards or technique information on various self drilling screws
Modified truss head self drilling screws drawings
Wafer head self drilling screws weight list (zinc and black)
Wafer head self drilling screws prices (IFI inch size)
Modified truss head self drilling screw prices (metric size)
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