Metallics QK1710M 8 x 1-1/2 in. 1/4 Hex Head Slotted Sharp Point Self-Piercing & Tapping Screws - Steel Zinc - Each

No pilot hole. The QK1710M is a sharp point self-piercing and tapping screw, so it pierces and forms its own thread as it drives. Twin lead threads cut the driving torque, which helps when you are running a lot of them by hand or with a screwgun.

It ships as a box with a 10,000 piece minimum, so this is a bulk buy for crews running a lot of sheet metal or strap work. Metallics does make other sizes and quantities available by request if a count that large does not suit the job.

Yes. The QK1710M is flagged compliant for both ARRA and Buy American requirements, which is what a government, school, or healthcare procurement file usually needs on a fastener line item. Country of origin is listed as multiple.

The head is a 1/4 inch hex with a slotted drive cut into it, so a 1/4 inch hex driver or socket is the fast way to run it, and a flat blade works when you cannot get a socket in. Head width measures 0.244 to 0.25 in. and head height 0.096 to 0.11 in., and the slot runs 0.045 to 0.054 wide and 0.052 to 0.074 deep.

Yes, there is a washer section under the hex head, 0.322 to 0.348 in. outside diameter and 0.019 to 0.031 in. thick. That gives you more bearing surface against sheet metal or a strap, and the undercut area beneath the head leaves more thread free for engagement in the material.

The QK1710M is steel with a zinc finish, which is a plated coating meant for dry interior and protected work, electrical boxes, strap, hangers, and sheet metal inside a building. For sustained exterior exposure or wet locations, step up to a stainless or hot dip coated fastener instead.

Thread count is 15 per inch on a #8 diameter, 1-1/2 inch long screw. The long shank is for reaching through standoffs, insulation, or stacked light gauge pieces, with the twin lead thread doing the tapping. Keep in mind head dimensions on self-piercing screws are not the same as standard tapping screws, and there is no single industry standard for them, so the published values are a guide.

Case hardness runs Rockwell C28-38, with the material to AISI 1018 to 1022 low carbon steel. That is the range that lets the sharp point pierce light gauge steel without the shank snapping off under driving torque.

The full 10,000 piece box is listed at 65.9 lbs, with carton measurements of 7.25 x 6.25 x 6 in. Plan on a two hand lift and a pallet or hand truck if you are ordering several.