A furniture screw can refer to any type of

screw A screw is an externally helical threaded fastener capable of being tightened or released by a twisting force (torque) to the screw head, head. The most common uses of screws are to hold objects together and there are many forms for a variety ...

(and sometimes

nut Nut often refers to: * Nut (fruit), fruit composed of a hard shell and a seed * Nut (food), a dry and edible fruit or seed, including but not limited to true nuts * Nut (hardware), fastener used with a bolt Nut, NUT or Nuts may also refer to: A ...

) used on

furniture Furniture refers to objects intended to support various human activities such as seating (e.g., Stool (seat), stools, chairs, and sofas), eating (table (furniture), tables), storing items, working, and sleeping (e.g., beds and hammocks). Furnitur ...

. Different types of screws have different uses in furniture. According to a 1986 article in New York Times, screws on old furniture can be difficult to remove due to rust.

Head types

Furniture screws come with many different types of screw heads. In older times, screws with slotted heads were often used in furniture, but these types of screw heads are usually avoided in modern furniture in favor of more practical tool slots. Popular options in the 2020s include Phillips,

Torx Torx (pronounced ) is a trademark for a type of screw drive characterized by a 6-point star-shaped pattern, developed in 1967, Bernard F. Reiland, "Coupling arrangement and tools for same", filed 1967-03-21 by Camcar Textron. A popular gener ...

and hex heads.

Wood screws

Wood screws are common in furniture in general, and for furniture uses they typically have diameters between 3.5 mm and 5 mm (#6/0.1380 in to #10/0.1900 in). A Chinese study published in 2019 which compared different types of screws used in

medium density fiberboard Medium-density fibreboard (MDF) is an engineered wood product made by breaking down hardwood or softwood residuals into wood fibre, often in a defibrator, combining it with wax and a resin binder, and forming it into panels by applying high tem ...

s (MDF) for furniture purposes found that the most important factor for how well a screw worked was the depth of the screw, and secondly the diameter of the hole. The screw type itself, however, had the least effect on the strength of the join.

Special furniture screws

Some common types of specialty furniture screws and bolts, especially on seen

ready-to-assemble furniture Ready-to-assemble furniture (RTA), also known as knock-down furniture (KD), flat-pack furniture, or kit furniture, is a form of furniture that requires customer assembly. The separate components are packed for sale in cartons containing assembl ...

, are: *

Barrel nut :''On some firearms the gun barrel is fastened to the receiver with a nut, referred to as a barrel nut.'' A barrel nut (also known as steel cross dowel or dowel nut) is a specialized forged nut, and is commonly used in aerospace and ready-to-asse ...

, a type of nut which has threads perpendicular to the cylinder axis * Cam fastener, used to provide resistance to special screws *

Confirmat screw Confirmat screws or cabinet-connecting screws are screws designed to hold in particleboard, medium-density fiberboard, and similar materials. They are very common furniture screw, in furniture assembly, but are rare in retail. They may have fla ...

, functions like a steel dowel, often comes with ready-to-assemble furniture made from MDF or other particle boards *

Insert nut An insert nut provides a threaded socket for a wooden workpiece, similar to a wall anchor. Insert nuts are inserted into a pre-drilled hole by one of two means: screw in and hammer in. In both cases, the external protrusions bite into the wood, ...

, a type of en type of threaded insert for wood *

Sex bolt Sex is the biological trait that determines whether a sexual reproduction, sexually reproducing organism produces male or female gametes. During sexual reproduction, a male and a female gamete fuse to form a zygote, which develops into an o ...

, a type of nut with a low shoulder (flange) to provide resistance with little protrusion *

T-nut A T-nut, T nut, or tee nut (also known as a blind nut, which can however also refer to a rivet nut or an insert nut, and likewise drive-in nut) is a type of nut used to fasten a wood, particle or composite materials workpiece, leaving a flush su ...

, a nut that can be knocked into the back of a wood plate to provide a screw mounting hole * Wood hanger screw, a screw with machine threads in one end, and wood screw threads in the other

Knock-down fastener

Knock-down fasteners are a class of

fasteners A fastener (US English) or fastening (UK English) is a hardware device that mechanically joins or affixes two or more objects together. In general, fasteners are used to create non-permanent joints; that is, joints that can be removed or disman ...

designed to allow for repeated assembly and disassembly. They are often used in flat pack furniture, which is typified by items such as book cases and wall units that come in a package of pre-cut and pre-drilled components ready to assemble by a novice. Knock-down fasteners can generally be assembled with a single driver, such as a

hex key A hex key (also, hex wrench, Allen key and Allen wrench, Unbrako or Inbus) is a simple driver for Bolt (fastener), bolts or screws that have heads with ''internal'' hexagonal recesses (Socket wrench, sockets). Hex keys are formed from a sin ...

, which may be included in a hardware kit that comes with the product. They self-align when tightened, and allow for a secure connection without requiring

drilling Drilling is a cutting process where a drill bit is spun to cut a hole of circular cross section (geometry), cross-section in solid materials. The drill bit is usually a rotary Cutting tool (machining), cutting tool, often multi-point. The bit i ...

gluing Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantage ...

by the consumer. One common type of knock-down fastener is the cam lock, used in

butt joint A butt joint is a joinery, wood joint in which the end of a piece of material is simply placed (or “butted”) against another piece. The butt joint is the simplest joint. An unreinforced butt joint is also the weakest joint, as it provides a ...

s. After two members are brought together, a cam lock in one member is twisted, locking onto a dowel extending from the second member, and securing the joint. Specialist tools and jigs are often required for the repeatable installation of knock-down fasteners (but not for assembly of prefabricated flat-pack furniture), so they tend to be limited to those who are making mass-produced items. However, there are applications in which the hobbyist can benefit from the range of fasteners that are available. They are easier and require less skill to install than some of the other more traditional techniques. Knock-down fasteners are typically used for carcase joinery; furniture designs using them are usually of frameless construction. Used for: Wide application in cabinet making depending on type of fastener: particularly in carcase construction (e.g. Carcase sides to top and bottom, fixed shelving/partitions, drawer boxes, counter tops to carcase)

Images of specialty screws

Cam connector cropped.png, Cam lock screw (right) with special steel dowel pin or screw (left) Sleeve nuts.jpg, Sex bolts, one with a bolt mounted Inslagmoer.JPG, T-nut Rampamuffe (klein).jpg, Insert nut for mounting in wood Quergewindebolzen QD-M6-7,5-13x16,2.jpg, Barrel nuts Stockschraube.jpg, Wood hanger screw

Anchoring furniture to walls

To prevent furniture from tipping over, which potentially can result in injury, furniture should be attached to walls. This is particularly important for tall and heavy furniture. Different types of screws can be used for this purpose depending on the wall material and construction.{{cite web, access-date=2023-04-08, language=en-JP, title=Secure it!｜IKEA Japan, url=https://www.ikea.com/jp/en/customer-service/product-support/assembly-guides/secure-it-pub96cab310, work=www.ikea.com If the wall has a suitable anchoring point (such as a

wall stud Wall studs are framing components in timber or steel-framed walls, that run between the top and bottom plates. It is a fundamental element in frame building. The majority non-masonry buildings rely on wall studs, with wood being the most common ...

) this may be suitable as an anchoring point using normal wood screws in a suitable size. On walls of plaster or masonry anchor points may not be available, and it can therefore be necessary to use a

drywall anchor A drywall anchor, also known as a wall anchor, is an insert that, combined with the appropriate screw, can create a strong mount anywhere on a drywall, drywall panel or similar hollow wall. A drywall anchor goes between the screw and the drywal ...

wall plug A wall plug (UK English) also known as an anchor (US) or " Rawlplug" (UK), is a fibre or plastic (originally wood) insert used to enable the attachment of a screw in a material that is porous or brittle, or that would otherwise not support the ...

, respectively.

References

External links

Video discussing when to use of screws versus wood joints in furniture construction (YouTube)

Guide to Woodworking Screws
Nuts (hardware) Woodworking