A ratchet (occasionally spelled rachet ) is a mechanical device that allows continuous linear or rotary motion in only one direction while preventing motion in the opposite direction. Ratchets are widely used in machinery and tools. The word ratchet is also used informally to refer to a ratcheting socket wrench .
17-651: Caulker may refer to: Caulking Caulker (surname) Caye Caulker , an island in the Caribbean Sea Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Caulker . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Caulker&oldid=937881981 " Category : Disambiguation pages Hidden categories: Short description
34-407: A joint material is silicone-based, it is considered a sealant rather than caulk. Ratchet (device) A ratchet consists of a round gear or a linear rack with teeth, and a pivoting, spring-loaded finger called a pawl (or click , in clocks and watches ) that engages the teeth. The teeth are uniform but are usually asymmetrical , with each tooth having a moderate slope on one edge and
51-414: A motor or by compressed air. Similar mechanisms are used for grease guns . For smaller applications, caulk may be distributed in squeeze tubes . Backer rod, also called backer material or back-up rod, is a flexible foam product used behind caulking to increase elasticity, reduce consumption, force the caulking into contact with the sides of the joint creating a better bond, determine the thickness of
68-412: A much steeper slope on the other edge. When the teeth are moving in the unrestricted (i.e. forward) direction, the pawl easily slides up and over the gently sloped edges of the teeth, with a spring forcing it (often with an audible 'click') into the depression between the teeth as it passes the tip of each tooth. When the teeth move in the opposite (backward) direction, however, the pawl will catch against
85-594: A similar way. Riveted seams in ships and boilers were formerly sealed by hammering the metal . Modern caulking compounds are flexible sealing compounds used to close up gaps in buildings and other structures against water , air , dust , insects , or as a component in firestopping . In the tunneling industry, caulking is the sealing of joints in segmental precast concrete tunnels, commonly by using concrete . Traditional caulking (also spelled calking) on wooden vessels uses fibers of cotton and oakum ( hemp ) soaked in pine tar . These fibers are driven into
102-473: A smooth, toothless ratchet with a high friction surface such as rubber is sometimes used. The pawl bears against the surface at an angle so that any backward motion will cause the pawl to jam against the surface and thus prevent any further backward motion. Since the backward travel distance is primarily a function of the compressibility of the high friction surface, this mechanism can result in significantly reduced backlash. In theoretical statistical physics ,
119-409: Is acrylic latex, for general-purpose use. Not only is acrylic latex inexpensive, but it is also the easiest type to apply smoothly and later paint if needed. Acrylic tile sealant usually comes in small tubes and is commonly used for wet applications. Polyurethane caulk is very durable and professional grade. Silicone caulk or sealant is water-, mold-, and mildew-resistant. Technically, when
136-431: Is different from Wikidata All article disambiguation pages All disambiguation pages Caulking Caulk or caulking is a material used to seal joints or seams against leakage in various structures and piping. The oldest form of caulk consisted of fibrous materials driven into the wedge-shaped seams between boards on wooden boats or ships . Cast iron sewerage pipes were formerly caulked in
153-457: Is the reason that open-cell backer rod was developed. Open-cell foam is porous so it will let gasses through which could otherwise cause blistering of the caulk or sealant. Additionally, open-cell backer rod allows air to get to the back side of the caulk or sealant which accelerates curing when used with air-cured sealants such as silicone . Open-cell rod is more compressible than closed-cell foam and should be compressed 25% to 75%. According to
170-470: The Consumer Federation of America , sealing unwanted leaks around homes is an excellent way to cut home energy costs and decrease the household carbon footprint . Also, sealing cracks and crevices around homes lessens the strain on home appliances and can save time, money and hassle by preventing major repairs. Sealing cracks and crevices prevents ingress by rodents. The most common type of caulk
187-432: The caulking of ships as a specialist skill. In riveted steel or iron ship construction , caulking was a process of rendering seams watertight by driving a thick, blunt chisel-like tool into the plating adjacent to the seam. This had the effect of displacing the metal into a close fit with the adjoining piece. Caulking of iron and steel, of the same type described above for ship's hulls, was also used by boilermakers in
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#1732855467337204-424: The caulking, and define the cross-section hour-glass shape of the caulk. The backer rod also acts as a bond breaker to keep the caulking from sticking to the bottom of the opening—called a three-sided bond—with the caulk only adhering to the sides of the opening in an hour-glass shape it can flex more easily and is less likely to tear. Backer rods can also be used to reduce consumption of the caulking by filling part of
221-401: The concept of a ratchet, often termed a " Brownian Ratchet ," is used to explain the origin of directed motion arising from a combination of time-reversal symmetry breaking and left-right symmetry breaking. When non-thermal forces (e.g. alternating pushes and pulls) are applied to an asymmetric substrate (e.g. an asymmetric gear), directed motion generically appears. This principle is known as
238-463: The era of riveted boilers to make the joints watertight and steamtight. For bulk use, caulk is generally distributed in disposable cartridges, which are rigid cylindrical cardboard or plastic tubes with an applicator tip at one end, and a movable plunger at the far end. These are used in caulking guns, which typically have a trigger connected to a rod which pushes the plunger, and has a ratchet to prevent backlash. The push rod may also be actuated by
255-432: The joints. Closed-cell foam does not absorb water and is impermeable. Closed-cell rods are less compressible and should not be compressed more than 25%. Closed-cell rod will also lose firmness and out-gas if damaged during installation or overcompressed or at sharp bends. The gasses cannot pass through this backer rod and can deform, weaken, and even cause holes (leaks) in the caulk or sealant as it escapes. Out-gassing
272-469: The steeply sloped edge of the first tooth it encounters, thereby locking it against the tooth and preventing any further motion in that direction. Because the ratchet can only stop backward motion at discrete points (i.e., at tooth boundaries), a ratchet does allow a limited amount of backward motion. This backward motion—which is limited to a maximum distance equal to the spacing between the teeth—is called backlash . In cases where backlash must be minimized,
289-463: The wedge-shaped seam between planks, with a caulking mallet and a broad chisel -like tool called a caulking iron. The caulking is then covered over with a putty , in the case of hull seams, or else in deck seams with melted pine pitch , in a process referred to as paying, or " calefaction ". Those who carried out this work were known as caulkers. In the Hebrew Bible , the prophet Ezekiel refers to
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