Choose the right cap head for your specific application. Apart from being available in above mentioned types, the screws are also available in various materials. Recommended for new designs to replace round, truss and binding heads. Bolt head on one end, threads on other end, used with a nut. Abbreviated pn truss an extra wide head with a rounded top. Provides a low large diameter head, but with characteristically high outer edge along the outer periphery of the head where drive action is most effective for high tightening torques. Type of heating cooling screw design type of screw design. Wood screws with cut threads have a maximum thread diameter that is no greater. True tamperresistant screw drives include the breakaway head and oneway screw drives. Flange bolts have a flange on the bottom of the head that distributes the load like a washer. Choose from our selection of socket head screws, rounded head screws, hex head screws, and more. A socket wrench is required to tighten or loosen it.
There are two types of stainless steel fasteners available, 304 and 316. Head types screw size conversion chart tamper resistant machine screws security fasteners, as the name indicates, are fasteners that provide an added level of security by their drive design that prevents removal with ordinary screw drivers. It was the first type of screw drive to be developed, and for centuries it was the simplest and cheapest to make. Screw which drills its own hole and then threads in.
Abbreviated fh oval a countersunk head with a rounded top. However, not much has changed in the technology of screws and their drivers, and the only real developments during. Finding the right type of screw head for your project when there are hundreds of combinations of the drive type and head shape can be confusing, especially for beginning diyers. Sheet metal screws are designed for connecting thinner metal objects to one another or connecting metal to wood, plastic, and other materials. For example, a phillips head screw would need a phillips head screwdriver. A low, large diameter head that can be used to cover. In addition to these markings, the head will often have a manufacturer stamp. To help, we prepared this guide to screw head types and drives. This is the traditional screw head in which used to be the only head type available. If youve ever gone to the tool box, grabbed a screwdriver, and realized you picked the wrong one, youve probably wondered why there are so many different kinds of screw head types in the first place. Bolts with a smooth rounded head that has a small square section underneath.
There are different types of screw heads which have different applications such as robertson, slotted and polydrive. A screw thread may be considered as a raised form known as a helix. Unless otherwise specified, screw threads are assumed to be righthanded. Apr 21, 2018 screwdrivers date back to the early 15th century, when they were invented to tighten the newlyinvented screws used in metal suits of armor and engines for war. The broadest categories are wood screws, sheet metal screws, drywall screws, deck screws, and lag screws. Provides a low large diameter head, but with characteristically high outer edge along the outer periphery of the head where driving action is most effective for high tightening torques. Stainless steel and aluminum fasteners repel rust and last for long periods of time. What are the different types of screws available in the. It also may include a specification of material and grade strength.
A screw is a shaft which has a groove on its surface. Flathead screws are meant to be countersunk flush or below the wood surface. Fastener guides screws head styles fastener superstore. Indented hex washer head sheet metal screws unslotted. Click on the image that looks most like the top of the screwhead to see the bit you need. Recommended for new designs to replace round, truss and. We have the charts to help you identify the many different types of bolts and screws for just about any project. Low head pressure high entrance pressure high screw speed high melt viscosity. The end of the screw is blunt, offering more thread engagement in short length applications. A helix is the curve defined by moving a point with uniform angular and linear velocity around an axis. Screws, and screwdrivers, have different types and sizes.
Although many people refer to any screw head that has crossshaped grooves as a phillips head, there are other types of screws that have similar slots. A medium low head with ordinarily sufficient bearing surface. If referring to internal thread tolerance, the g would be uppercase. Vectorized version by sakurambo of screw head types. Shs socket head ap screw sms sheet metal screw sq square, can refer to square head bolt or square nut ss or ss stainless steel st steel t. A socket cap screw, also known as a socket head capscrew, socket screw, or allen bolt, is a type of cap screw with a cylindrical head and hexagonal drive hole. The second is to house the drive, or the means by which force is applied to drive the screw in or remove it, if required. The unthreaded portion prevents two wood pieces from separating as they are screwed together.
Sems screw with a permanently attached washer serrated locking serrations on bearing face of screw or nut shs socket head ap screw sms sheet metal screw sq square, can refer to square head bolt or square nut ss or ss stainless steel st steel t. Another type is a threadcutting machine screw, which has a head that cuts its own threads as it goes into a hole. Washers are commonly used under the heads of bolts and screws and they are used under nuts as well. Types of screws 5 every diyer should know bob vila. Pan head most common type of roundedtop screw head. With the help of below charts you can identify almost any type of bolt and screw different types of fasteners, head styles in fasteners, drive types in fasteners, washer types in fasteners and nut types in fasteners. Socket head cap screws socket screws and set screws. Secondary to drive type is the material the screw is made to go into such as wood, sheet metal or drywall and the shape of its head. Below is your basic guide to screw head styles and their uses. This type of screw has the benefit of being made precisely, but the disadvantage is that the cutting tool cuts through the crystalline metal structure. When your jobs requires usage of screws then always remember to go for the right type of screw.
The advantage is that little or no part of the head protrudes beyond the surface of the material. Heres a brief yet comprehensive guide to screw head types and drives. The bugle head screw is a modern variation of the basic flathead screw. Bolts with a hexagonal head with threads for use with a nut or tapped hole. Cheat guide chart bolts, screws, washers, nuts, drive charts working on a project and trying to find the name of a special bolt type.
Head type of bolts hexagon head bolt usually uses nut heavy duty hexagon head cap screw thinner head often used as screw in threaded hole, without nut socket head cap screw usually more precision applications access from the top machine screws usually smaller sizes slot or philips head common. Jul 07, 2015 at mutual screw and supply, we field several calls from our esteemed clients, seeking help in choosing right bit of screw head types, appropriate for their requirements. Jul 07, 2015 such types of fasteners either feature a hexagonal recession in the head or do not have grooves at all. Or a screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the straight threads and later known as tapered threads. There are different types of screw heads which have different applications such as. If you are using flat heads screws in finish work, consider using a flat head screw cover also known as a beauty cap to hide the head not all drive styles will accept screw covers. Simply knowing the head type on a screw or bolt can let you know what type of screwdriver or socket type you will need so. Simply knowing the head type on a screw or bolt can let you know what type of screwdriver or socket type you will need so you do not strip or cross thread your fastener. Though those head types are quite common, there are many other variations, including some that are meant to resist attempts at removal.
Button head cap screw 1 notes 2 precision socket screws metric type pshld 3 precision shoulder screws precision shoulder screw cross recess head 4 precision shoulder screw socket head 5 precision slotted shoulder screw head 6 sheet metal screws, thread forming metric type b 7 pan head sheet metal screw, pan head 8. Through hardened type of heat treatment tir total indicator reading ts tapping screw tpi threads per inch tth threaded to head type 1 23, 25 special thread forming or cutting tapping screws. The type b is the most popular thread in the sheet metal family. Machine screw selection guide head types screw size. The slotted head is basically one line through the middle of the head in which the screwdriver would fit. The point is, before you go all bruce willis on a screw, make sure the screwdriver head fits snugly. The screw s precision comes at the expense of a loss of strength. Provides a low large diameter head, but with characteristically high outer edge along the periphery of the head where driving action is most effective for high tightening torques. Made of plastic, these caps are available in standard colors that match commonly used plastic laminates and wood. Socket head cap screws are commonly used in machine assembly, especially for removable panels and parts.
Different types of screw heads soon came out in the late 1900s. Geometrically, a screw thread is a helical incline plane. Nails and screws that are for use outdoors must be able to withstand rain, snow, heat and cold. Then theres the less common torx or star head, a super cool sixpointed starshaped head, which is used on things that need to get very tight. Used with drilled, punched or nested holes in sheet metal,resin impregnated plywood, asbestos combinations, among others. Type 17 type bp type a type b type bt25 type c type t23 type d1 type f type g type bf type u type tt type ca dog point. Head types screws have one of three basic types of head. At mutual screw and supply, we field several calls from our esteemed clients, seeking help in choosing right bit of screw head types, appropriate for their requirements heres a brief yet comprehensive guide to screw head types and drives. The remaining onethird of the shank under the head remains unthreaded.
Through hardened type of heat treatment tir total indicator reading ts tapping screw. Slightly different head contour where supplied with. Recent widespread availability of assorted drive bits including security types minimizes this advantage, at least for some fastener types. We carry security fasteners in many head styles, drives and matching tools for their installation and.
The hex socket screw allen screw requires an allen wrench, featuring a hexagonal shaft and the other type of hex screw s head is completely hexagonal in shape. The slot screw drive has a single slot in the fastener head and is driven by a common blade or flatbladed screwdriver. Abbreviated rh hex a hexagonal head abbreviated hh or hx socket cap a small cylindrical head using a socket drive. Chart showing 60 types of screws, screw heads, bolts, nuts and washers chart. There are also specialty screws for specific applications, such as concrete screws. The square head screw has a square recess in its head. The term socket head capscrew typically refers to a type of threaded fastener whose head diameter is nominally 1. When your jobs requires usage of screws then always remember to go for the right type of screw driver. This is a flat head wood screw with a tapped hole in the head, which receives a screw in chromeplated cover. Screws types of screw threads screw thread terminology. In this post you will learn screw, screw thread terminology, types of screw threads. Mar 21, 2020 although many people refer to any screw head that has crossshaped grooves as a phillips head, there are other types of screws that have similar slots. The most common type of washers is the flat washer.
Different types of screws heads that you must know. Denominations tend to describe the use or position of the screw as often as it describes individual screw characteristics. Everything in this world is designed for a specific reason and so as the head style. Metric edition common screw thread points type a type ab type b type z type bf use. Identification charts for different types of fasteners. Traditional wood screws production screws 14 38 12 58 34 1 1 14 1 12 1 34 2 2 14 2 12 2 34 3 3 14 3 12 3 34 4 gauge 23 4567 8 9 10 12 14 6 8 10 head bore size shankhole size pilothole size hardwood softwood available lengths phillips head point size squaredrive bit size. The screwdriver must be the correct type to fit the certain screw head.
Slightly different head contour where supplied with recessed head. Round washer head creates larger bearing surface in. Find out more about the different types of heads available for wood screws. They are sometimes notched at the tip to aid in chip removal during thread cutting. Blunt point metric self tapping screws type f description a thread forming, tapping screw with spaced threads and a blunt point with incomplete entering threads.
Round head becoming less common, but offers an appearance alternative from other rounded head screws. Hardened thread screw made to cut or form its own mating thread in an untapped hole. About 43% of these are screws, 1% are rivets, and 1% are window and door making machine. Type b sheet metal screws have the same thread as the type ab. Recommended for new designs to replace round, truss and binding. A brief introduction to the different types of screw heads. Screw thread design screw thread fundamentals a screw thread is defined as a ridge of uniform section in the form of a helix on either the external or internal surface of a cylinder. Used in many applications when a flat bottomed screw is required. You must countersink the hole before driving the screws illus. Can be successfully substituted for many similar head styles. It is designed to hold objects in a certain alignment. A cross head features two fulllength slots that cross, which allows a flat head screwdriver to be used and makes the screw usable even if one slot has been worn away. This head has a flat top, allowing it to be driven into a tapered hole with the head set below the wood surface.
Knowing the names and the specific types of screws, bolts, washers, or nuts you will need for your current or future diy project is very important. They have a round cap with a hex head and are tightened with a socket wrench drive. Understanding screw heads and drive styles fastener mart. Cheat guide chart bolts, screws, washers, nuts, drive. In addition to screw drives, various nut drives have been designed to make removal difficult without specialized tools. Also known as oven head, stove head, and oval binding head. Screw head types a guide to what type of screw is this. Has sharp threads that cut into a material such as sheet metal, plastic or wood.
Countersunk flat head screws common head style with type h or type z cross recess product grade a part 2. Screw threads serve three basic functions in mechanical systems. The robertson screw with a square head came out in 1908, the phillips head screw was invented in 1930, and tiny screws often found in gadgets such as iphones and laptops were introduced in the 21st century. Sep 30, 2016 with the help of below charts you can identify almost any type of bolt and screw different types of fasteners, head styles in fasteners, drive types in fasteners, washer types in fasteners and nut types in fasteners. A wide variety of screw head types options are available to you, such as free samples, paid samples. The hex socket screwallen screw requires an allen wrench, featuring a hexagonal shaft and the other type of hex screws head is completely hexagonal in shape. We make it our business to supply you with the durable hardware in the quantities you need. Screw design basics the processor point of view andrew w. The most common types here in the us are phillips head and slot head. Fastener type chart bolt depot nuts and bolts, screws.
Below is an extensive list of screws that are readily available from both manufacturers and hardware stores. Applications advantages for molded or through holes in thin metal, nonferrous castings, plastics or resinfilled plywood. Although it is not as widely available as the phillips head screw, it is increasingly popular among wood workers because it offers an even better grip for the screwdriver bit. You must have done many projects in which requirement of screws were necessary, but you may not have ever wondered that why there are so many different types of head over the screw. Wood screws with cut threads are tapered and approximately twothirds of their length is threaded. Not recommended as a phillips recessed head see pan head for better functional design. Abbreviated oh or ov pan a slightly rounded head with short vertical sides. The term socket head cap screw typically refers to a type of threaded fastener whose head diameter is nominally 1. Uniquely among common drives, it is straightforward to manufacture a slot head or drive by hand. Plastics, fibre cement and similar composites type bp type bt type 25 type c type ca use. With slot head screwdrivers its even simpler, the blades are measured in fractions of an inch. Internal threads refer to those on nuts and tapped holes, while external threads are those on bolts, studs, or screws.