FURNITURE & CABINETRY SCREWS HEAD & DRIVE STYLES Wood screws come in a number of different head styles to fit a number of different needs and applications. Slotted Phillips FLAT Flat top surface with a countersunk bearing surface. FLAT UNDERCUT Provides a flush surface in countersunk holes. The bottom of the head is undercut to ensure full thread engagement. Length is measured from the top of the head. FLAT WITH NIBS Designed to sit flush with the surface of the material it’s binding. A characteristic of flat head screws is the cone-shaped bearing surface under the head. On the bottom part of the head as part of the bevel there are several ridges or nibs designed to help lock the head in place in furniture or particle board. ROUND WASHER A rounded head style with a flanged washer. Typically used in applications that require a low clearance and a wide bearing surface. It is preferred in situations of aesthetics for it’s smooth appearance. This style has a flange around the outside similar to a washer to increase bearing force. Phillips Square Square MODIFIED TRUSS HEAD Low Head profile & large load bearing surface. Offers largest diameter. Ideal for use in enlarged holes. ROUND The head protrudes above the material surface, length is measured from under the head. Dome head has a flat bearing surface and general bearing strength. Is preferred in situations of aesthetics for it’s smooth appearance. OVAL Protrudes slightly above the material surface in countersunk holes with slightly rounded top for a more finished look. Length is measured from the edge of the head. The head is raised allowing a deeper drive slot for more driving force. PAN Offers low clearance from the low profile, large diameter head. Slightly rounded top surface and short vertical sides. Length is measured from under the head. Can be used in most situations when general bearing strength is needed. Six Lobe Hex Washer TRUSS Also known as oven head or stove head screws, Truss Head Screws have the largest head diameter of all head styles. Ideal for use in enlarged holes. Truss Heads have a low, rounded top with a flat bearing surface. Length is measured from under the head. BUGLE A common head style for drywall and wood applications, because of its ability to sink in with minimal damage to the material’s surface. The countersunk bugle shaped head style mounts flush with the mating surface. FILLISTER Maximize driving power by combining the greatest head height and the smallest head diameter you can get in a machine screw. Length is measured from under the head. POINT STYLES Screws come in a number of different thread and point styles to fit different needs and applications. TYPE A These thread forming screws are for use in thin metal. .015 to .05 inches thick. Used with drilled, punched out holes in sheet metal, resin impregnated plywood, and asbestos combinations. TYPE B These are thick forming screws for use in heavier metal .050 to .20 inches thick. They also require a drilled or punched hoe and have a larger root diameter with finer thread pitch for light and heavy sheet metal non-ferrous castings, plastics, impregnated plywood, asbestos combinations, and other materials. TRI-LOBULAR Thread rolling screws have a triround cross section to provide relief areas when rolling internal threads. Used in metals to eliminate tapping. TYPE 17 These thread cutting screws have a coarse tapping screw thread and a special long sharp point fluted to capture wood chips. SHARP Common in wood screws, this design allows screw to penetrate through wood smoothly with less material splitting. DOUBLE CUT TYPE 17 Similar to the Type 17 point, with an additional cutting slot in the threads. For use in wood when pre-drilling isn’t practical. 2 Learn more at www.fastenal.com
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