Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Plaster shopping experience:
1. Compare - without doubt the biggest advantage that the Plaster offers shoppers today is the ability to compare thousands of Plaster at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.
2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about
3. Testimonials - don't know anybody that has bought a Plaster? Wrong! If the Plaster is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.
4. Questions - Got a question about Plaster then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....
5. Reputation - Never heard of the company selling Plaster? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Plaster and build up a picture of their reputation for sales, returns, customer service, delivery etc.
6. Returns - still worried that even after all of the above your Plaster wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.
7. Feedback - happy with your Plaster then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.
8. Security - check for the yellow padlock on the Plaster site before you buy, and the s after http:/ /i.e. https:// = a secure site
9. Contact - got a question about Plaster, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.
10. Payment - ready to pay for your Plaster, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.
based
plaster used in spray
fireproofing in a low-rise industrial
building in
Vancouver, British Columbia.
Plaster of Paris, or simply
plaster, is a type of building material based on
calcium sulfate hemihydrate, nominally CaSO4·0.5H2O. It is created by heating gypsum to about 150 °C.
2CaSO4·4H2O → 2CaSO4·H2O + 3H2O (released as steam).
A large gypsum deposit at
Montmartre in
Paris is the source of the name.http://www.bartleby.com/61/63/P0356300.html When the dry plaster powder is mixed with water, it re-forms into gypsum. Plaster is used as a building material similar to
Mortar (masonry) or cement. Like those materials plaster starts as a dry powder that is mixed with water to form a paste, which then hardens. Unlike
Mortar (masonry) and
cement, plaster remains quite soft after drying, and can be easily manipulated with metal tools or even sandpaper. These characteristics make plaster suitable for a finishing, rather than a load-bearing material.
Use in room interiors
Plaster was a common building material for wall surfaces in a process known as lath and plaster, whereby a series of wooden strips are covered with a semi-dry plaster and then hardened into surface. The plaster used in most lath-and-plaster construction was mainly lime plaster (see below). Lime plaster cure time is about a month. To stabilize the lime plaster during curing, small amounts of Plaster of Paris were mixed into the putty. Because Plaster of Paris sets quickly, "retardants" were used to slow setting time enough to allow workers to mix large working quantities of lime putty plaster. A modern form of this method uses expanded metal mesh over wood or metal structures, which allows a great freedom of design as it is adaptable to both simple and compound curves. Today this building method has been partly replaced with
drywall, also composed mostly of gypsum plaster. In both these methods a primary advantage of the material is that it is resistant to a fire within a room and so can assist in reducing or eliminating structural damage or destruction provided the fire is promptly extinguished.
Plaster moulding (decorative) is made using a sliding jig that holds a die with a cross section of the moulding.
Use in theatrical and movie sets
One of the skills used in movie and theatrical sets is that of "plasterer", and the material is often used to simulate the appearance of surfaces of wood, stone, or metal.Nowadays, plasterers are just as likely to use
expanded polystyrene, although the job title remains unchanged.
Use in architecture
in Kashan,
Iran.Plaster may also be used to create complex detailing for use in room interiors. These may be geometric (simulating wood or stone) or naturalistic (simulating leaves, vines, and flowers) These are also often used to simulate wood or stone detailing found in more substantial buildings.
Use in The Arts
Many of the greatest paintings in Europe, like Michelangelo's Sistine Chapel ceiling are executed in
Fresco, meaning they are painted on a thin layer of wet plaster, called
intonaco (in fact the general term for plaster in Italian); the pigments sink into this layer so that the plaster itself becomes the medium holding them, which accounts for the excellent durability of fresco. Additional work may be added
a secco on top of the dry plaster, though this is generally less durable.
Plaster may be cast directly into a damp clay mold. In creating this
moldmolds (molds designed for making multiple copies) or
waste molds (for single use) would be made of plaster. This "negative" image, if properly designed, may be used to produce clay productions, which when fired in a kiln become terra cotta building decorations, or these may be used to create cast
concrete sculptures. If a plaster positive was desired this would be constructed or cast to form a durable image artwork. As a model for stonecutters this would be sufficient. If intended for producing a bronze casting the plaster positive could be further worked to produce smooth surfaces. An advantage of this plaster image is that it is relatively cheap; should a patron approve of the durable image and be willing to bear further expense, subsequent molds could be made for the creation of a wax image to be used in
lost wax casting, a far more expensive process. In lieu of producing a bronze image suitable for outdoor use the plaster image may be painted to resemble a metal image; such sculptures are suitable only for presentation in a weather-protected environment.
image:sch_op_8.jpgPlaster expands while hardening, then contracts slightly just before hardening completely. This makes plaster excellent for use in molds, and it is often used as an artistic material for casting. Plaster is also commonly spread over an armature (form), usually made of wire, mesh or other materials.
Plaster is often used in
Faux Finishing to create textures for wall and furniture surfaces, as in
Venetian Plaster and also in stenciling for raised details. For these processes, artists use limestone based plasters or new user friendly acrylic based plaster.
Use in medicine
Plaster is widely used as a support for broken bones; a bandage impregnated with plaster is moistened and then wrapped around the damaged limb, setting into a close-fitting yet easily removed tube, known as a Cast (orthopedic); however, this is slowly being replaced by a fibreglass variety.
Plaster is also used within radiotherapy when making immobilisation casts for patients. Plaster bandages are used when constructing an impression of the patients head and neck, and liquid plaster is used to fill the impression and produce a plaster bust. Perspex is then vacuum formed over this bust creating an immobilisation shell.
In dentistry, plaster is used for mounting and flasking casts or models of oral tissues. These diagnostic and working models are made from dental stone, a stronger, harder and denser derivative of plaster which is manufactured from gypsum under pressure.
Lime plaster
Lime plaster is a mixture of calcium hydroxide and sand (or other inert fillers). Carbon dioxide in the atmosphere causes the plaster to set by transforming the calcium hydroxide into calcium carbonate (limestone).
Whitewash is based on the same chemistry.
To make lime plaster,
Limestone (calcium carbonate) is heated to produce quicklime (calcium oxide). Water is then added to produce slaked lime (calcium hydroxide), which is sold as a white powder. Additional water is added to form a paste prior to use. The paste may be stored in air tight containers. Once exposed to the atmosphere, the calcium hydroxide turns back into limestone, causing the plaster to set.
Lime plaster is used for true
frescoes. Pigments, diluted in water, are applied to the still wet plaster.
Earthen plaster
Earthen plaster is a mixture of clay, sand and fibre. One of the most common fibres used is straw, although animal hair or dung has been a common additive over the centuries. Earthen plaster has seen a recent resurgence in its use in conjunction with strawbale building. Earthen plaster can be scuplted and colored by the type of clay used or other mineral additives. Other common additives and finishes to earthen plaster include cactus juice, casein, and linseed oil. See also
Earthen_Floor and
cob (building).
Cement plaster
Cement plaster is a mixture of suitable plaster sand,
portland cement and water which is normally applied to masonry interiors and exteriors to achieve a smooth surface. Interior surfaces sometimes receive a final layer of gypsum plaster. Walls constructed with London stock bricks are normally plastered while
Brickwork walls are not plastered. Various cement-based plasters are also used as proprietary spray fireproofing products, the world over. These usually use vermiculite as lightweight aggregate. Heavy versions of such plasters are also in use for exterior fireproofing, to protect LPG vessels, pipe bridges and vessel skirts.
Passive fire protection
Plasters have been in use in passive fire protection, as fireproofing products, for many decades. They are subject to stringent bounding.The plaster provides a layer of thermal insulation to retard heat flow into
structural steel elements, that would otherwise lose their strength and collapse in a fire. Early versions of these plasters have used asbestos fibres, which have by now been outlawed in industrialised nations and have caused significant Asbestos abatement and re-coating work. More modern plasters fall into the following categories:
- fibrous (including mineral wool)
- cement mixtures either with mineral wool or with vermiculite
- gypsum plasters, leavened with polystyrene beads, as well as chemical expansion agents to decrease the density of the finished product
One differentiates between interior and exterior fireproofing. Interior products are typically less substantial, with lower densities and lower cost. Exterior products have to withstand more extreme fire and other environmental conditions. Exterior products are also more likely to be attractively tooled, whereas their interior cousins are usually merely sprayed in place. A rough surface is typically forgiven inside of buildings as dropped ceilings often hide them. Exterior fireproofing plasters are losing ground to more costly intumescent and
endothermic products, simply on technical merit. Trade jurisdiction on unionised construction sites in
North America remains with the plasterers, regardless of whether the plaster is decorative in nature or is used in passive fire protection. Cementitious and gypsum based plasters tend to be endothermic. Fireproofing plasters are closely related to firestop mortars. In fact, most firestop mortars can be sprayed and tooled very well, due to the fine detail work that is required of firestopping, which leads their mix designers to utilise
concrete addmixtures, that enable easier tooling than common mortars.
Trade jurisdiction
In unionized construction sites in North America, plaster is installed by contractors signatory to the Operative Plasterers’ and Cement Masons’ International Association (OPCMIA), which represents unionized plasterers.
Safety issues
The chemical reaction that occurs when plaster sets is exothermic in nature. The danger of this was illustrated in January 2007, when a sixteen year-old girl suffered third-degree burns after encasing her hands in plaster as part of a school art project in
Lincolnshire, England. She subsequently had her thumbs and most of her fingers amputated.http://news.bbc.co.uk/1/hi/education/6485481.stm In place of plaster,
alginate should be used for casting body parts.
Some variations of plaster that contain powdered silica or asbestos may present health hazards if inhaled. Asbestos is a known carcinogen when inhaled in powder form, especially in people who smoke, and inhalation can also cause asbestosis. Inhaled silica can cause silicosis and (in very rare cases) can encourage the development of cancer. Persons working regularly with plaster containing these additives should take precautions to avoid inhaling powdered plaster, cured or uncured. (Note that asbestos is rarely used in modern plaster formulations because of its carcinogenic effects.)
See also
References
External links
- International Union of Bricklayers and Allied Craftworkers
- Plasterers Union
based
plaster used in spray fireproofing in a low-rise industrial building in Vancouver,
British Columbia.
Plaster of Paris, or simply
plaster, is a type of building material based on calcium sulfate hemihydrate, nominally CaSO4·0.5H2O. It is created by heating gypsum to about 150 °C.
2CaSO4·4H2O → 2CaSO4·H2O + 3H2O (released as steam).
A large gypsum deposit at Montmartre in Paris is the source of the name.http://www.bartleby.com/61/63/P0356300.html When the dry plaster powder is mixed with water, it re-forms into gypsum. Plaster is used as a building material similar to
Mortar (masonry) or
cement. Like those materials plaster starts as a dry powder that is mixed with water to form a paste, which then hardens. Unlike
Mortar (masonry) and cement, plaster remains quite soft after drying, and can be easily manipulated with metal tools or even
sandpaper. These characteristics make plaster suitable for a finishing, rather than a load-bearing material.
Use in room interiors
Plaster was a common building material for wall surfaces in a process known as lath and plaster, whereby a series of wooden strips are covered with a semi-dry plaster and then hardened into surface. The plaster used in most lath-and-plaster construction was mainly lime plaster (see below). Lime plaster cure time is about a month. To stabilize the lime plaster during curing, small amounts of Plaster of Paris were mixed into the putty. Because Plaster of Paris sets quickly, "retardants" were used to slow setting time enough to allow workers to mix large working quantities of lime putty plaster. A modern form of this method uses expanded metal mesh over wood or metal structures, which allows a great freedom of design as it is adaptable to both simple and compound curves. Today this building method has been partly replaced with
drywall, also composed mostly of gypsum plaster. In both these methods a primary advantage of the material is that it is resistant to a fire within a room and so can assist in reducing or eliminating structural damage or destruction provided the fire is promptly extinguished.
Plaster
moulding (decorative) is made using a sliding jig that holds a
die with a cross section of the moulding.
Use in theatrical and movie sets
One of the skills used in movie and theatrical sets is that of "plasterer", and the material is often used to simulate the appearance of surfaces of wood, stone, or metal.Nowadays, plasterers are just as likely to use expanded polystyrene, although the job title remains unchanged.
Use in architecture
in Kashan,
Iran.Plaster may also be used to create complex detailing for use in room interiors. These may be geometric (simulating wood or stone) or naturalistic (simulating leaves, vines, and flowers) These are also often used to simulate wood or stone detailing found in more substantial buildings.
Use in The Arts
Many of the greatest paintings in Europe, like Michelangelo's Sistine Chapel ceiling are executed in
Fresco, meaning they are painted on a thin layer of wet plaster, called intonaco (in fact the general term for plaster in Italian); the pigments sink into this layer so that the plaster itself becomes the medium holding them, which accounts for the excellent durability of fresco. Additional work may be added
a secco on top of the dry plaster, though this is generally less durable.
Plaster may be cast directly into a damp clay mold. In creating this
moldmolds (molds designed for making multiple copies) or
waste molds (for single use) would be made of plaster. This "negative" image, if properly designed, may be used to produce clay productions, which when fired in a kiln become
terra cotta building decorations, or these may be used to create cast
concrete sculptures. If a plaster positive was desired this would be constructed or cast to form a durable image artwork. As a model for stonecutters this would be sufficient. If intended for producing a bronze casting the plaster positive could be further worked to produce smooth surfaces. An advantage of this plaster image is that it is relatively cheap; should a patron approve of the durable image and be willing to bear further expense, subsequent molds could be made for the creation of a wax image to be used in lost wax casting, a far more expensive process. In lieu of producing a bronze image suitable for outdoor use the plaster image may be painted to resemble a metal image; such sculptures are suitable only for presentation in a weather-protected environment.
image:sch_op_8.jpgPlaster expands while hardening, then contracts slightly just before hardening completely. This makes plaster excellent for use in molds, and it is often used as an artistic material for casting. Plaster is also commonly spread over an armature (form), usually made of wire, mesh or other materials.
Plaster is often used in
Faux Finishing to create textures for wall and furniture surfaces, as in
Venetian Plaster and also in stenciling for raised details. For these processes, artists use limestone based plasters or new user friendly acrylic based plaster.
Use in medicine
Plaster is widely used as a support for broken bones; a bandage impregnated with plaster is moistened and then wrapped around the damaged limb, setting into a close-fitting yet easily removed tube, known as a Cast (orthopedic); however, this is slowly being replaced by a fibreglass variety.
Plaster is also used within radiotherapy when making immobilisation casts for patients. Plaster bandages are used when constructing an impression of the patients head and neck, and liquid plaster is used to fill the impression and produce a plaster bust. Perspex is then vacuum formed over this bust creating an immobilisation shell.
In dentistry, plaster is used for mounting and flasking casts or models of oral tissues. These diagnostic and working models are made from dental stone, a stronger, harder and denser derivative of plaster which is manufactured from gypsum under pressure.
Lime plaster
Lime plaster is a mixture of calcium hydroxide and sand (or other inert fillers). Carbon dioxide in the atmosphere causes the plaster to set by transforming the calcium hydroxide into calcium carbonate (limestone). Whitewash is based on the same chemistry.
To make lime plaster, Limestone (calcium carbonate) is heated to produce
quicklime (calcium oxide). Water is then added to produce slaked lime (calcium hydroxide), which is sold as a white powder. Additional water is added to form a paste prior to use. The paste may be stored in air tight containers. Once exposed to the atmosphere, the calcium hydroxide turns back into limestone, causing the plaster to set.
Lime plaster is used for true
frescoes.
Pigments, diluted in water, are applied to the still wet plaster.
Earthen plaster
Earthen plaster is a mixture of clay, sand and fibre. One of the most common fibres used is straw, although animal hair or dung has been a common additive over the centuries. Earthen plaster has seen a recent resurgence in its use in conjunction with strawbale building. Earthen plaster can be scuplted and colored by the type of clay used or other mineral additives. Other common additives and finishes to earthen plaster include cactus juice, casein, and linseed oil. See also Earthen_Floor and
cob (building).
Cement plaster
Cement plaster is a mixture of suitable plaster sand,
portland cement and water which is normally applied to masonry interiors and exteriors to achieve a smooth surface. Interior surfaces sometimes receive a final layer of gypsum plaster. Walls constructed with
London stock bricks are normally plastered while Brickwork walls are not plastered. Various cement-based plasters are also used as proprietary spray fireproofing products, the world over. These usually use
vermiculite as lightweight aggregate. Heavy versions of such plasters are also in use for exterior fireproofing, to protect LPG vessels, pipe bridges and vessel skirts.
Passive fire protection
Plasters have been in use in
passive fire protection, as fireproofing products, for many decades. They are subject to stringent
bounding.The plaster provides a layer of thermal insulation to retard
heat flow into
structural steel elements, that would otherwise lose their strength and collapse in a fire. Early versions of these plasters have used asbestos fibres, which have by now been outlawed in industrialised nations and have caused significant Asbestos abatement and re-coating work. More modern plasters fall into the following categories:
- fibrous (including mineral wool)
- cement mixtures either with mineral wool or with vermiculite
- gypsum plasters, leavened with polystyrene beads, as well as chemical expansion agents to decrease the density of the finished product
One differentiates between interior and exterior fireproofing. Interior products are typically less substantial, with lower densities and lower cost. Exterior products have to withstand more extreme fire and other environmental conditions. Exterior products are also more likely to be attractively tooled, whereas their interior cousins are usually merely sprayed in place. A rough surface is typically forgiven inside of buildings as dropped ceilings often hide them. Exterior fireproofing plasters are losing ground to more costly
intumescent and endothermic products, simply on technical merit. Trade jurisdiction on unionised construction sites in
North America remains with the plasterers, regardless of whether the plaster is decorative in nature or is used in passive fire protection. Cementitious and gypsum based plasters tend to be
endothermic. Fireproofing plasters are closely related to firestop mortars. In fact, most firestop mortars can be sprayed and tooled very well, due to the fine detail work that is required of firestopping, which leads their mix designers to utilise concrete addmixtures, that enable easier tooling than common mortars.
Trade jurisdiction
In unionized construction sites in North America, plaster is installed by contractors signatory to the Operative Plasterers’ and Cement Masons’ International Association
(OPCMIA), which represents unionized plasterers.
Safety issues
The chemical reaction that occurs when plaster sets is
exothermic in nature. The danger of this was illustrated in January 2007, when a sixteen year-old girl suffered third-degree burns after encasing her hands in plaster as part of a
school art project in Lincolnshire,
England. She subsequently had her thumbs and most of her fingers amputated.http://news.bbc.co.uk/1/hi/education/6485481.stm In place of plaster, alginate should be used for casting body parts.
Some variations of plaster that contain powdered silica or asbestos may present health hazards if inhaled. Asbestos is a known
carcinogen when inhaled in powder form, especially in people who smoke, and inhalation can also cause asbestosis. Inhaled silica can cause silicosis and (in very rare cases) can encourage the development of cancer. Persons working regularly with plaster containing these additives should take precautions to avoid inhaling powdered plaster, cured or uncured. (Note that asbestos is rarely used in modern plaster formulations because of its carcinogenic effects.)
See also
References
External links
- International Union of Bricklayers and Allied Craftworkers
- Plasterers Union
The Polished Plaster Company
ekm:metadescription> ... Polished Plaster what is it? It is a stunning decorative wall finish made from fine lime putty,marble flour or grains, natural waxes and colorants, applied ...
Definition: plaster from Online Medical Dictionary
The Online Medical Dictionary is a searchable dictionary of definitions from medicine, science and technology.
"Polished plaster company, Polished Plaster also known as venetian ...
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Architectural Plaster Coving, Mouldings and GRP Exteriors - HODKIN ...
Hodkin and Jones manufacture a range of plaster coving products and classical mouldings for interior and exterior decoration. Please feel free to browse our online catalogue of ...
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Hodkin and Jones manufacture a range of plaster coving products and classical mouldings for interior and exterior decoration
Plaster - Wikipedia, the free encyclopedia
The term plaster can refer to plaster of Paris, lime plaster, or cement plaster. This article deals mainly with plaster of Paris. Plaster of Paris is a type of building material ...
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Suppliers of plaster and wooden fire surrounds and plaster period mouldings at factory prices. Includes available products, and contact details.
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Plaster Renovations a Name you can Trust. ... Plaster Renovations has been serving the South East community since 1975.
Regency Plaster Products,Archways,Ceiling Roses,Cornices,Fire ...
Regency Plaster products can be easily fitted by professionals and DIY novices alike. We provide a wide range of products from Archways, Ceiling Roses, Cornices, Fire Surrounds ...
Fibrous plaster mouldings – Venetian plaster – Ital Plaster ...
Ital Plaster are experienced in the manufacture of fibrous plaster mouldings and specialists in the supply and application of venetian plaster
