Metallics JDS178V 14 x 1-1/2 in. 3/8 Indented Hex Head Slotted Sharp Point Tapping Screws - Steel Zinc - Each

The JDS178V is a #14 x 1-1/2 inch Type A tapping screw with a gimlet (sharp) point. Type A threads with a sharp point are the sheet metal screw you reach for in thin gauge steel, sheet metal duct, and similar light sheet work, where the point starts the hole and the coarse 10 threads per inch pull in fast. It is not a machine screw and not a self-drilling screw, so a pilot hole is needed in heavier stock.

Either. The head is an indented hex with a slot cut across it, so a 3/8 inch nut driver or hex socket seats on the head, and a flat blade fits the slot when you cannot get a driver square to the work. Head width measures 0.367 to 0.375 in. across the flats and 0.409 across the corners, and the slot runs 0.064 to 0.075 in. wide by 0.083 to 0.101 in. deep.

Torsional strength is rated at 125 lb-in minimum, and the screws are case hardened to Rockwell C28-38 from AISI 1016-1024 steel. That is the hardness range a Type A sheet metal screw needs to form its own thread in thin steel without shearing the head off. In heavier stock, drill a pilot hole sized for the #14 body rather than relying on the gimlet point.

Metallics lists the JDS178V as both ARRA compliant and Buy American compliant, which is what a government, school, or healthcare procurement file usually needs on the submittal. Country of origin is listed as multiple.

Yes, it is a hex washer head style. The integral washer measures 0.480 to 0.520 in. outside diameter and 0.030 to 0.050 in. thick, which spreads the clamp load over sheet metal and oversized or slotted holes without adding a loose washer. Overall head height is 0.172 to 0.19 in.

These are carbon steel with a zinc finish. Zinc plating handles indoor and protected work, light moisture and general electrical rough-in. For sustained exterior exposure, standing moisture, or coastal air, step up to a stainless or hot-dip galvanized fastener instead, since plated zinc on steel will eventually bleed rust in those conditions.

They ship in a jar of 500, and 500 count is the order minimum. Weight is 10.05 lbs per jar. Other sizes and quantities can be arranged by request.

Head and dimensional conformance is to ASME B18.6.3-2010, threads to ASME B18.6.4, and material to AISI 1016-1024. One note for the engineer reviewing it: dimensions for #9 diameter in this family are independent of ASME B18.6.4.

At 1-1/2 inches of thread, it is sized for going through two layers or a thicker assembly, not for fastening a cover to a box. If you are only catching a single sheet of steel, the point will protrude well past the back and the extra length buys nothing, so a shorter #14 in the same JDS indented hex head slotted range is the better call. Where the screw has to pass a clamp, strap, or bracket and still bite the substrate, the 1-1/2 inch length is the one you want.