Epoxy Talk

Discussion in 'Growing Marijuana Indoors' started by geneticengineer, Nov 28, 2010.

  1. Just figured it would be a good idea to start this thread. Hell I think it should even be stickied. Resins can have a lot of use in grow-system design as it does not leach into water and forms solid bonds as well as a waterproofing laminate or sealant.

    Epoxy resins can also be used to construct composite fibers like carbon fiber, fiberglass, and kevlar composites. These are used in aerospace and marine applications where strength and lightweight materials are needed.

    I now use epoxies for everything including but not limited to making grow beds and reservoirs from scratch. I will be updating this thread and I would like to see how people respond to it before I vest any more time here.

    If you have experience with epoxy resins, or are interested in learning please post in this thread. I have added a video here to stimulate interested readers, and I have included some information from wikipedia.

    Peace and Love

    -E

    [ame=http://www.youtube.com/watch?v=iIM5_9Kx68I]YouTube - Epoxy Laminating Systems[/ame]


    Epoxy

    From Wikipedia, the free encyclopedia

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    Epoxy or polyepoxide is a thermosetting polymer formed from reaction of an epoxide "resin" with polyamine "hardener". Epoxy has a wide range of applications, including fiber-reinforced plastic materials and general purpose adhesives.
    Contents

    [hide]
    [edit] Chemistry

    [​IMG] [​IMG]
    Structure of unmodified epoxy prepolymer. n denotes the number of polymerized subunits and is in the range from 0 to about 25


    Epoxy is a copolymer; that is, it is formed from two different chemicals. These are referred to as the "resin" and the "hardener". The resin consists of monomers or short chain polymers with an epoxide group at either end. Most common epoxy resins are produced from a reaction between epichlorohydrin and bisphenol-A, though the latter may be replaced by similar chemicals. The hardener consists of polyamine monomers, for example Triethylenetetramine (TETA). When these compounds are mixed together, the amine groups react with the epoxide groups to form a covalent bond. Each NH group can react with an epoxide group, so that the resulting polymer is heavily crosslinked, and is thus rigid and strong.[1][2]
    The process of polymerization is called "curing", and can be controlled through temperature and choice of resin and hardener compounds; the process can take minutes to hours. Some formulations benefit from heating during the cure period, whereas others simply require time, and ambient temperatures.
    [edit] History

    The first commercial attempts to prepare resins from epichlorohydrin were made in 1927 in the United States. Credit for the first synthesis of bisphenol-A-based epoxy resins is shared by Dr. Pierre Castan of Switzerland and Dr. S.O. Greenlee of the United States in 1936. Dr. Castan's work was licensed by Ciba, Ltd. of Switzerland, which went on to become one of the three major epoxy resin producers worldwide. Ciba's epoxy business was spun off and later sold in the late 1990s and is now the advanced materials business unit of Huntsman Corporation of the United States. Dr. Greenlee's work was for the firm of Devoe-Reynolds of the United States. Devoe-Reynolds, which was active in the early days of the epoxy resin industry, was sold to Shell Chemical (now Hexion, formerly Resolution Polymers and others).
    [edit] Applications

    The applications for epoxy-based materials are extensive and include coatings, adhesives and composite materials such as those using carbon fiber and fiberglass reinforcements (although polyester, vinyl ester, and other thermosetting resins are also used for glass-reinforced plastic). The chemistry of epoxies and the range of commercially available variations allows cure polymers to be produced with a very broad range of properties. In general, epoxies are known for their excellent adhesion, chemical and heat resistance, good-to-excellent mechanical properties and very good electrical insulating properties. Many properties of epoxies can be modified (for example silver-filled epoxies with good electrical conductivity are available, although epoxies are typically electrically insulating). Variations offering high thermal insulation, or thermal conductivity combined with high electrical resistance for electronics applications, are available.[3]
    [edit] Paints and coatings

    Two part epoxy coatings were developed for heavy duty service on metal substrates and use less energy than heat-cured powder coatings. These systems use a 4:1 by volume mixing ratio, and dry quickly providing a tough, UV resistant[citation needed], protective coating with excellent hardness. Their low volatility and water clean up makes them useful for factory cast iron, cast steel, cast aluminum applications and reduces exposure and flammability issues associated with solvent-borne coatings. They are usually used in industrial and automotive applications since they are more heat resistant than latex-based and alkyd-based paints.
    Polyester epoxies are used as powder coatings for washers, driers and other "white goods". Fusion Bonded Epoxy Powder Coatings (FBE) are extensively used for corrosion protection of steel pipes and fittings used in the oil and gas industry, potable water transmission pipelines (steel), concrete reinforcing rebar, et cetera. Epoxy coatings are also widely used as primers to improve the adhesion of automotive and marine paints especially on metal surfaces where corrosion (rusting) resistance is important. Metal cans and containers are often coated with epoxy to prevent rusting, especially for foods like tomatoes that are acidic. Epoxy resins are also used for high performance and decorative flooring applications especially terrazzo flooring, chip flooring[4] and colored aggregate flooring.[5]
    [edit] Adhesives

    [​IMG] [​IMG]
    Special epoxy is strong enough to withstand the forces between a surfboard fin and the fin mount. This epoxy is waterproof and capable of curing underwater. The blue-coloured epoxy on the left is still undergoing curing.


    Epoxy adhesives are a major part of the class of adhesives called "structural adhesives" or "engineering adhesives" (that includes polyurethane, acrylic, cyanoacrylate, and other chemistries.) These high-performance adhesives are used in the construction of aircraft, automobiles, bicycles, boats, golf clubs, skis, snowboards, and other applications where high strength bonds are required. Epoxy adhesives can be developed to suit almost any application. They can be used as adhesives for wood, metal, glass, stone, and some plastics. They can be made flexible or rigid, transparent or opaque/colored, fast setting or slow setting. Epoxy adhesives are better in heat and chemical resistance than other common adhesives. In general, epoxy adhesives cured with heat will be more heat- and chemical-resistant than those cured at room temperature. The strength of epoxy adhesives is degraded at temperatures above 350 F (177 C).[6]
    Some epoxies are cured by exposure to ultraviolet light. Such epoxies are commonly used in optics, fiber optics, optoelectronics, and dentistry.[citation needed]
    [edit] Industrial tooling and composites

    Epoxy systems are used in industrial tooling applications to produce molds, master models, laminates, castings, fixtures, and other industrial production aids. This "plastic tooling" replaces metal, wood and other traditional materials, and generally improves the efficiency and either lowers the overall cost or shortens the lead-time for many industrial processes. Epoxies are also used in producing fiber-reinforced or composite parts. They are more expensive than polyester resins and vinyl ester resins, but usually produce stronger and more temperature-resistant composite parts.
    [edit] Electrical systems and electronics

    [​IMG] [​IMG]
    An epoxy encapsulated hybrid circuit on a printed circuit board.


    Epoxy resin formulations are important in the electronics industry, and are employed in motors, generators, transformers, switchgear, bushings, and insulators. Epoxy resins are excellent electrical insulators and protect electrical components from short circuiting, dust and moisture. In the electronics industry epoxy resins are the primary resin used in overmolding integrated circuits, transistors and hybrid circuits, and making printed circuit boards. The largest volume type of circuit board—an "FR-4 board"—is a sandwich of layers of glass cloth bonded into a composite by an epoxy resin. Epoxy resins are used to bond copper foil to circuit board substrates, and are a component of the solder mask on many circuit boards.
    Flexible epoxy resins are used for potting transformers and inductors. By using vacuum impregnation on uncured epoxy, winding-to-winding, winding-to-core, and winding-to-insulator air voids are eliminated. The cured epoxy is an electrical insulator and a much better conductor of heat than air. Transformer and inductor hot spots are greatly reduced, giving the component a stable and longer life than unpotted product.
    Epoxy resins are applied using the technology of resin dispensing.
    [edit] Consumer and marine applications

    Epoxies are sold in hardware stores, typically as a pack containing separate resin and hardener, which must be mixed immediately before use. They are also sold in boat shops as repair resins for marine applications. Epoxies typically are not used in the outer layer of a boat because they deteriorate by exposure to UV light. They are often used during boat repair and assembly, and then over-coated with conventional or two-part polyurethane paint or marine-varnishes that provide UV protection.
    There are two main areas of marine use. Because of the better mechanical properties relative to the more common polyester resins, epoxies are used for commercial manufacture of components where a high strength/weight ratio is required. The second area is that their strength, gap filling properties and excellent adhesion to many materials including timber have created a boom in amateur building projects including aircraft and boats.
    Normal gelcoat formulated for use with polyester resins and vinylester resins does not adhere to epoxy surfaces, though epoxy adheres very well if applied to polyester resin surfaces. "Flocoat" that is normally used to coat the interior of polyester fibreglass yachts is also compatible with epoxies.
    Polyester thermosets typically use a ratio of at least 10:1 of resin to hardener (or "catalyst"), while epoxy materials typically use a lower ratio of between 5:1 and 1:1. Epoxy materials tend to harden somewhat more gradually, while polyester materials tend to harden quickly.
    While it is common to associate polyester resins and epoxy resins, their properties are sufficiently different that they should actually be treated as separate materials. Epoxy resins typically require a precise mix of two components which form a third chemical. Depending on the properties required, the ratio may be anything from 1:1 or over 10:1, but in every case they must be mixed exactly. The final product is then a thermo-setting plastic. Until they are mixed the two elements are relatively inert, although the 'hardeners' tend to be more chemically active and should be protected from the atmosphere and moisture. The rate of the reaction can be changed by using different hardeners, which also changes the nature of the final product, or by controlling the temperature.
    By contrast, polyester resins are usually made available in a 'promoted' form, such that the progress of previously-mixed resins from liquid to solid is already underway, albeit very slowly. The only variable available to the user is to change the rate of this process using a catalyst, often Methyl-Ethyl-Ketone-Peroxide (MEKP), which is very toxic. The presence of the catalyst in the final product actually detracts from the desirable properties, so that small amounts of catalyst are preferable, so long as the hardening proceeds at an acceptable pace. The rate of cure of polyesters can therefore be controlled both by the amount of catalyst and by the temperature.
    As adhesives, epoxies bond in three ways: a) Mechanically, because the bonding surfaces are roughened; b) By proximity, because the cured resins are physically so close to the bonding surfaces that they are hard to separate; c) Ionically, because the epoxy resins form ionic bonds at an atomic level with the bonding surfaces. This is substantially the strongest of the three. By contrast, polyester resins can only bond using the first two of these, which greatly reduces their utility as adhesives and in marine repair.
    [edit] Aerospace applications

    In the aerospace industry, epoxy is used as a structural matrix material which is then reinforced by fiber. Typical fiber reinforcements include glass, carbon, Kevlar, and boron. Epoxies are also used as a structural glue. Materials like wood, and others that are 'low-tech' are glued with epoxy resin. One example would be the RJ.03 IBIS homebuilt canard aircraft. This design is based on a classic wooden lattice structured fuselage and a classic wooden spar, internally stiffened with foam and completely covered with plywood. Except for the plywood covering the wings, everything is glued with epoxy resin.
    [edit] Art

    Epoxy resin, mixed with pigment, is used as a painting medium, by pouring layers on top of each other to form a complete picture.[7]
    [edit] Wind Energy applications

    Epoxy resin is used in manufacturing the rotor blades of wind turbines. The resin is infused in the core materials, such as balsa wood or foam, and the reinforcing media, such as fabric, glass fibre or carbon fibre. The process is called VARTM, i.e. Vacuum Assisted Resin Transfer Moulding. Due to excellent properties and good finish, epoxy is the most favoured resin for composites.
    [edit] Industry

    As of 2006, the epoxy industry amounts to more than US$5 billion in North America and about US$15 billion worldwide. The Chinese market has been growing rapidly, and accounts for more than 30% of the total worldwide market. It is made up of approximately 50–100 manufacturers of basic or commodity epoxy resins and hardeners of which the three largest are Hexion (formerly Resolution Performance Products, formerly Shell Development Company; whose epoxy tradename is "Epon"), the Dow Chemical Company (tradename "D.E.R."), and Huntsman Corporation's Advanced Materials business unit (formerly Vantico, formerly Ciba Specialty Chemical; tradename "Araldite"). In 2007 Huntsman Corporation agreed to merge with Hexion (owned by the Apollo Group).[8][9] KUKDO Chemical is one of the largest epoxy manufacturers in Asia, and recently their capacity has been increased up to 210,000 MT/Y (Korea 150,000 MT/Y, China 60,000 MT/Y and will be increased totally 300,000 MT/Y by 2009). Nanya Plastic also has the capacity of over 250,000 MT/Y (Taiwan and China), which is mostly for captive use. There are over 50 smaller epoxy manufacturers primarily producing epoxies only regionally, epoxy hardeners only, specialty epoxies, or epoxy modifiers.
    These commodity epoxy manufacturers mentioned above typically do not sell epoxy resins in a form usable to smaller end users, so there is another group of companies that purchase epoxy raw materials from the major producers and then compounds (blends, modifies, or otherwise customizes) epoxy systems from these raw materials. These companies are known as "formulators". The majority of the epoxy systems sold are produced by these formulators and they comprise over 60% of the dollar value of the epoxy market. There are hundreds of ways that these formulators can modify epoxies—by adding mineral fillers (talc, silica, alumina, etc.), by adding flexibilizers, viscosity reducers, colorants, thickeners, accelerators, adhesion promoters, etc.. These modifications are made to reduce costs, to improve performance, and to improve processing convenience. As a result a typical formulator sells dozens or even thousands of formulations—each tailored to the requirements of a particular application or market.
    Impacted by the global economic slump, the epoxy market size declined to $15.8 billion in 2009, almost to the level of 2005. In some regional markets it even decreased nearly 20%. The current epoxy market is experiencing positive growth as the global economy revives. With an annual growth rate of 3.5 - 4% the epoxy market is expected to reach $17.7 billion by 2012 and $21.35 by 2015. Higher growth rate is foreseen thereafter due to stronger demands from epoxy composite market and epoxy adhesive market.[10]
    [edit] Health risks

    The primary risk associated with epoxy use is sensitization to the hardener, which, over time, can induce an allergic reaction. It is a main source of occupational asthma among users of plastics.[11] Bisphenol A, which is used in epoxy resin, is a known endocrine disruptor.
     

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  2. some more videos to spark your imagination and unlock the possibilities :)



    [ame=http://www.youtube.com/watch?v=-9pIZXy_y2s]YouTube - Mold Making - Surface Casting[/ame]

    [ame=http://www.youtube.com/watch?v=IAdVO8Rkv6c&feature=related]YouTube - How To Make Your Own Carbon Fiber (Fibre) Parts.[/ame]

    [ame=http://www.youtube.com/watch?v=DwI0FJTy4ys&feature=related]YouTube - Preparation of Mould[/ame]

    [ame=http://www.youtube.com/watch?v=UCOziXeTXzY&feature=related]YouTube - West System G-Flex Epoxy![/ame]

    [ame=http://www.youtube.com/watch?v=TDI9uD2C5Hk&feature=related]YouTube - West System Applying Fabrics[/ame]



    Peace and Love;

    -E
     
  3. dang. did anyone even read this? would love to expound on my experience with building systems. you can make a grow bed for roughly 50-80 dollars, and it will perform better than any bed purchased from a hydro shop. all it takes is a bit of patience and experience with resin/fiberglass composites.
     
  4. If I could learn this it would be awesome. You could custom make your containers into any shape. That would be handy.
     
  5. hey bro...you know im readin' it...you spent some time to post this..and if i dont use it in my grow..i'll use it during everyday life a ton...thanks so much for takin' the time..learn this and you can make just about anything:wave:
     
  6. yep. thanks guys and indeed this is true.

    it is kind of a big undertaking, but i have found its easier than it appears. the only drawback is the initial investment for some good marine-grade epoxy can be substantial, as can the time to learn how to use it correctly with fiberglass. after copious research i recommend using marine grade because it is specifically designed for applications involving water and long term reliability under duress and weathering conditions.

    you can make a grow table/bed using a core like plywood, 2x4s, and bolts. one can shape the wetted out fiberglass to cover all the surface areas. it works much better to coat the individual pieces one by one (legs, plywood tabletop, etc) before assembling them. after they are assembled its important to go over it 2-3x over every square inch to effectuate a seal against moisture for the wood.

    there are fillers that can be used like colloidal silica, which thicken the epoxy to a paste. this can be used as a fairing mixture (fairing is going over the final product to ensure smoothness and fairness to the eye, streamlining and making it appear as one solid piece). you can then sand and 1 more clear coat would also help to ensure dozens of years of continues operation.

    these tables can hold much more than your average 4x4 prefab growbed purchased at a hydro store. infact they can hold literally thousands of pounds of water, lavarock(or any other medium), and plantmass. these beds are impervious to physical damage.

    epoxies can break down under uv light and there are steps to ensure this does not happen. after talking with a resin-guru at a marine supply shop, i was assured this break down under uv light takes many years and meerly makes the resin turn yellow. coats of paint can help this, maybe a coat right under the last clearcoat-there are also laminates and coatings that can be used but due to their toxicity would not be applicable to growing cannabis.

    the beauty of epoxy resins is that they are inert plastics and do not leach into the water. infact they leach less into the water than the plastic in your average drinking-water bottle.

    man im sorry i dont have pictures guys, but just use your imagination. you can turn a piece of plywood into something so structurally sound you dont even need to reinforce the bottom when making a growbed. my newer growbeds are going to be 4x8 for simplicity and efficiency in delivering lumens when using multiple lights in a string.

    having a bigger bed like 4x8 can be difficult because of the volume of water needed to flood it. i use autosiphons for many reasons i wont go into now. traditional flood and drain would not really work for this and probably clog the pumps with debris. these tables have to be built for long terb sustainance, and employ large drains in the center with 3" pipes to ensure there are no clogs due to roots or lavarock. i could probably draw a diagram of one of these fittings if i could find a graphical program on this computer (this computer is not mine).

    in any case thanks for the interest and i will be walking people through the finer points of this approach to grow-system design (i say system because it can be used with soil) in the future so please make sure and check instant notification on this thread so you can see when something comes up.

    peace and love;

    -E
     

    Attached Files:

  7. good stuff...i will be usin' this when i get to fully convert my grow room..thanks bro.....wheres all the diy guys:confused:
     
  8. Good thinking I have worked with fiberglass and carbon fiber on racecars and have never thought about using them with my grow I could use a good size custom catch pan now you have me thinking THANX I alreary think to much when I'm medicated:smoke:
     
  9. i like to stir the pot, no pun intended. but yea it can be usefull and its worth the time if you got enough of it.

    -E
     
  10. ok I have made some great progress with epoxies. i am going to buy a camera today to take pictures...
     
  11. hey bro...great ta see ya back..hope things are smoother sailin' for ya now:smoke:drop by my thread anytime...peace deacon:smoke:
     
  12. thanks brother will do.

    Ok. I don't have my camera yet. This is the 75 gallon reservoir for the mother/propogation section. I used various composites and fillers in combination with the epoxy resin.

    The ball valve assembly for return plumbing is wrapped in 6 layers of fiberglass and armored by a 1 cm layer of steel reinforced blue tinted resin. This ensures that even if the spigot is stepped on it will not break...
     

    Attached Files:

  13. in a structure like that where would be the greatest stress generated by the weight of the water..lower corners:confused:
     
  14. yes. and all the seams in general, the water puts out a lot of structural force.

    its all fiberglassed and layered with 6 coats of resin. the plywood is only 1/2" but its completely rigid from the E-glass epoxy composite. the sides do not give it all when all the way full.

    :hello:
     
  15. #15 geneticengineer, Mar 25, 2011
    Last edited by a moderator: Mar 26, 2011
    I'm looking into using carbon fiber for some of my new components. These videos demonstrate the efficiency which can be achieved using carbon fiber as a building material. It is very strong, rigid, and light weight (not a lot is needed).

    [ame=http://www.youtube.com/watch?v=mRefml7THbY&feature=related]YouTube - ING F1: Carbon Fibre explained[/ame]

    [ame=http://www.youtube.com/watch?v=MFNaoklYELY&feature=related]]YouTube - How It's Made Carbon Fiber Car Parts[/ame]

    This is an advanced construction material and should be used with proper equipment and procedures.

    Epoxy-resin is used in combination with the carbon fabric to construct abrasive resistant laminates (layered composites) which act as a shell to its core. This can be used in many engineering applications and verily be used in hydroponic system design because of its attributes; light weight, high tensile strength, rigidness, and near-impermeability once wetted out.

    Most people buy hydro trays which are constructed from abs or similar polymer composites. These are very shallow and weak and falter when dealing with various advanced techniques such as aquaponics. A 1 foot deep grow bed is preferred over 7" grow trays because of the full submersion of pots, and deep root development if using an open media techniques such as in aquaponics.

    Furniture quality trays/beds are better in my opinion for flood and drain applications because of their depth, strength, abrasion resistance, lack of leaching, and long life.


    E
    :hello:

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    \t\t\t \t\t\t\t\t\t \t\t\tCarbon-fiber-reinforced polymer

    \t\t\t \t\t\t \t\t\t \t\t\t\t \t\t\t\tFrom Wikipedia, the free encyclopedia
    \t\t\t\t \t\t\t\t \t\t\t\t (Redirected from Carbon fiber)
    \t\t\t\t \t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t \t\t\t\t \t\t\t\t \t\t\t\t\t\t\t\t \t\t\t\t [​IMG] [​IMG]
    Tail of an RC helicopter, made of CFRP


    For fibers of carbon, see carbon (fiber).
    Carbon-fiber-reinforced polymer or carbon-fiber-reinforced plastic (CFRP or CRP), is a very strong, light, and expensive composite material or fiber-reinforced polymer. Similar to fiberglass (glass reinforced polymer), the composite material is commonly referred to by the name of its reinforcing fibers (carbon fiber). The polymer is most often epoxy, but other polymers, such as polyester, vinyl ester or nylon, are sometimes used. Some composites contain both carbon fiber and other fibers such as Kevlar, aluminium, and fiberglass reinforcement. The terms graphite-reinforced polymer or graphite fiber-reinforced polymer (GFRP) are also used, but less commonly, since glass-(fiber)-reinforced polymer can also be called GFRP. In product advertisements, it is sometimes referred to simply as graphite fiber (or graphite fibre), for short.
    It has many applications in aerospace and automotive fields, as well as in sailboats, and notably in modern bicycles and motorcycles, where its high strength-to-weight ratio is of importance. Improved manufacturing techniques are reducing the costs and time to manufacture, making it increasingly common in small consumer goods as well, such as laptops, tripods, fishing rods, paintball equipment, archery equipment, racquet frames, stringed instrument bodies, classical guitar strings, drum shells, golf clubs, and pool/billiards/snooker cues.
    Contents

    [hide]

    [edit] Composite

    Materials produced with the above-mentioned methodology are often generically referred to as composites. The choice of matrix can have a profound effect on the properties of the finished composite. One method of producing graphite-epoxy parts is by layering sheets of carbon fiber cloth into a mold in the shape of the final product. The alignment and weave of the cloth fibers is chosen to optimize the strength and stiffness properties of the resulting material. The mold is then filled with epoxy and is heated or air-cured. The resulting part is very corrosion-resistant, stiff, and strong for its weight. Parts used in less critical areas are manufactured by draping cloth over a mold, with epoxy either preimpregnated into the fibers (also known as prepreg) or "painted" over it. High-performance parts using single molds are often vacuum-bagged and/or autoclave-cured, because even small air bubbles in the material will reduce strength.
    [edit] Process

    The process by which most carbon fiber-reinforced polymer is made varies, depending on the piece being created, the finish (outside gloss) required, and how many of this particular piece are going to be produced.
    For simple pieces of which relatively few copies are needed, (1–2 per day) a vacuum bag can be used. A fiberglass, carbon fiber or aluminum mold is polished and waxed, and has a release agent applied before the fabric and resin are applied, and the vacuum is pulled and set aside to allow the piece to cure (harden). There are two ways to apply the resin to the fabric in a vacuum mold. One is called a wet layup, where the two-part resin is mixed and applied before being laid in the mold and placed in the bag. The other is a resin induction system, where the dry fabric and mold are placed inside the bag while the vacuum pulls the resin through a small tube into the bag, then through a tube with holes or something similar to evenly spread the resin throughout the fabric. Wire loom works perfectly for a tube that requires holes inside the bag. Both of these methods of applying resin require hand work to spread the resin evenly for a glossy finish with very small pin-holes. A third method of constructing composite materials is known as a dry layup. Here, the carbon fiber material is already impregnated with resin (prepreg) and is applied to the mold in a similar fashion to adhesive film. The assembly is then placed in a vacuum to cure. The dry layup method has the least amount of resin waste and can achieve lighter constructions than wet layup. Also, because larger amounts of resin are more difficult to bleed out with wet layup methods, prepreg parts generally have fewer pinholes. Pinhole elimination with minimal resin amounts generally require the use of autoclave pressures to purge the residual gases out.
    A quicker method uses a compression mold. This is a two-piece (male and female) mold usually made out of fiberglass or aluminum that is bolted together with the fabric and resin between the two. The benefit is that, once it is bolted together, it is relatively clean and can be moved around or stored without a vacuum until after curing. However, the molds require a lot of material to hold together through many uses under that pressure.
    Many carbon fiber-reinforced polymer parts are created with a single layer of carbon fabric, and filled with fiberglass. A tool called a chopper gun can be used to quickly create these types of parts. Once a thin shell is created out of carbon fiber, the chopper gun is a pneumatic tool that cuts fiberglass from a roll and sprays resin at the same time, so that the fiberglass and resin are mixed on the spot. The resin is either external mix, wherein the hardener and resin are sprayed separately, or internal, where they are mixed internally, which requires cleaning after every use.
    For difficult or convoluted shapes, a filament winder can be used to make pieces.
    [edit] Automotive uses

    [​IMG]
    This section does not cite any references or sources.
    Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (July 2008) Carbon fiber-reinforced polymer is used extensively in high-end automobile racing. The high cost of carbon fiber is mitigated by the material's unsurpassed strength-to-weight ratio, and low weight is essential for high-performance automobile racing. Racecar manufacturers have also developed methods to give carbon fiber pieces strength in a certain direction, making it strong in a load-bearing direction, but weak in directions where little or no load would be placed on the member. Conversely, manufacturers developed omnidirectional carbon fiber weaves that apply strength in all directions. This type of carbon fiber assembly is most widely used in the "safety cell" monocoque chassis assembly of high-performance racecars.
    Many supercars over the past few decades have incorporated CFRP extensively in their manufacture, using it for their monocoque chassis as well as other components.
    Until recently, the material has had limited use in mass-produced cars because of the expense involved in terms of materials, equipment, and the relatively limited pool of individuals with expertise in working with it. Recently, several mainstream vehicle manufacturers have started to use CFRP in everyday road cars.
    Use of the material has been more readily adopted by low-volume manufacturers who used it primarily for creating body-panels for some of their high-end cars due to its increased strength and decreased weight compared with the glass-reinforced polymer they used for the majority of their products.
    [edit] Civil engineering applications

    Carbon fiber reinforced polymer-[CFRP] has over the past two decades become an increasingly notable material used in structural engineering applications. Studied in an academic context as to its potential benefits in construction, it has also proved itself cost-effective in a number of field applications strengthening concrete, masonry, steel, cast iron, and timber structures. Its use in industry can be either for retrofitting to strengthen an existing structure or as an alternative reinforcing (or prestressing material) instead of steel from the outset of a project.
    Retrofitting has become the increasingly dominant use of the material in civil engineering, and applications include increasing the load capacity of old structures (such as bridges) that were designed to tolerate far lower service loads than they are experiencing today, seismic retrofitting, and repair of damaged structures. Retrofitting is popular in many instances as the cost of replacing the deficient structure can greatly exceed its strengthening using CFRP.[1]
    Applied to reinforced concrete structures for flexure, CFRP typically has a large impact on strength (doubling or more the strength of the section is not uncommon), but only a moderate increase in stiffness (perhaps a 10% increase). This is because the material used in this application is typically very strong (e.g., 3000 MPa ultimate tensile strength, more than 10 times mild steel) but not particularly stiff (150 to 250 GPa, a little less than steel, is typical). As a consequence, only small cross-sectional areas of the material are used. Small areas of very high strength but moderate stiffness material will significantly increase strength, but not stiffness.
    CFRP can also be applied to enhance shear strength of reinforced concrete by wrapping fabrics or fibers around the section to be strengthened. Wrapping around sections (such as bridge or building columns) can also enhance the ductility of the section, greatly increasing the resistance to collapse under earthquake loading. Such 'seismic retrofit' is the major application in earthquake-prone areas, since it is much more economic than alternative methods.
    If a column is circular (or nearly so) an increase in axial capacity is also achieved by wrapping. In this application, the confinement of the CFRP wrap enhances the compressive strength of the concrete. However, although large increases are achieved in the ultimate collapse load, the concrete will crack at only slightly enhanced load, meaning that this application is only occasionally used.
    Specialist ultra-high modulus CFRP (with tensile modulus of 420 GPa or more) is one of the few practical methods of strengthening cast-iron beams. In typical use, it is bonded to the tensile flange of the section, both increasing the stiffness of the section and lowering the neutral axis, thus greatly reducing the maximum tensile stress in the cast iron.
    When used as a replacement for steel, CFRP bars could be used to reinforce concrete structures, however the applications are not common.
    CFRP could be used as prestressing materials due to their high strength. The advantages of CFRP over steel as a prestressing material, namely its light weight and corrosion resistance, should enable the material to be used for niche applications such as in offshore environments. However, there are practical difficulties in anchorage of carbon fiber strands and applications of this are rare.
    In the United States, Prestressed Concrete Cylinder Pipes (PCCP) account for a vast majority of water transmission mains. Due to their large diameters, failures of PCCP are usually catastrophic and affect large populations. Approximately 19,000 miles of PCCP have been installed between 1940 and 2006. Corrosion in the form of hydrogen embrittlement has been blamed for the gradual deterioration of the prestressing wires in many PCCP lines. Over the past decade, CFRPs have been utilized to internally line PCCP, resulting in a fully structural strengthening system. Inside a PCCP line, the CFRP liner acts as a barrier that controls the level of strain experienced by the steel cylinder in the host pipe. The composite liner enables the steel cylinder to perform within its elastic range, to ensure the pipeline's long-term performance is maintained. CFRP liner designs are based on strain compatibility between the liner and host pipe.[2]

    CFRP is a more costly material than its counterparts in the construction industry, glass fiber-reinforced polymer (GFRP) and aramid fiber-reinforced polymer (AFRP), though CFRP is, in general, regarded as having superior properties.
    Much research continues to be done on using CFRP both for retrofitting and as an alternative to steel as a reinforcing or prestressing material. Cost remains an issue and long-term durability questions still remain. Some are concerned about the brittle nature of CFRP, in contrast to the ductility of steel. Though design codes have been drawn up by institutions such as the American Concrete Institute, there remains some hesitation among the engineering community about implementing these alternative materials. In part, this is due to a lack of standardization and the proprietary nature of the fiber and resin combinations on the market, though this in itself is advantageous in that the material properties can be tailored to the desired application requirements.
    [edit] Other applications

    [​IMG] [​IMG]
    A carbon fiber and Kevlar canoe (Placid Boatworks Rapidfire at the Adirondack Canoe Classic)


    Carbon fiber-reinforced polymer has found a lot of use in high-end sports equipment such as racing bicycles. For the same strength, a carbon-fiber frame weighs less than a bicycle tubing of aluminum[citation needed] or steel. The choice of weave can be carefully selected to maximize stiffness. The variety of shapes it can be built into has further increased stiffness and also allowed aerodynamic considerations into tube profiles. Carbon fiber-reinforced polymer frames, forks, handlebars, seatposts, and crank arms are becoming more common on medium- and higher-priced bicycles. Carbon fiber-reinforced polymer forks are used on most new racing bicycles. Other sporting goods applications include rackets, fishing rods, longboards, and rowing shells.
    Much of the fuselage of the new Boeing 787 Dreamliner and Airbus A350 XWB will be composed of CFRP, making the aircraft lighter than a comparable aluminum fuselage, with the added benefit of less maintenance thanks to CFRP's superior fatigue resistance[citation needed].
    Due to its high ratio of strength to weight, CFRP is widely used in micro air vehicles (MAVs). In MAVSTAR Project, the CFRP structures reduce the weight of the MAV significantly. In addition, the high stiffness of the CFRP blades overcome the problem of collision between blades under strong wind.
    CFRP has also found application in the construction of high-end audio components such as turntables and loudspeakers, again due to its stiffness.
    It is used for parts in a variety of musical instruments, including violin bows, guitar pickguards, and a durable ebony replacement for bagpipe chanters. It is also used to create entire musical instruments such as Blackbird Guitars carbon fiber rider models, Luis and Clark carbon fiber cellos, and Mix carbon fiber mandolins.
    In firearms it can substitute for metal, wood, and fiberglass in many areas of a firearm in order to reduce overall weight. However, while it is possible to make the receiver out of synthetic material such as carbon fiber, many of the internal parts are still limited to metal alloys as current reinforced plastics are unsuitable replacements.
    Shoe manufacturers use carbon fiber as a shank plate in their basketball sneakers to keep the foot stable. It usually runs the length of the sneaker just above the sole and is left exposed in some areas, usually in the arch of the foot.
    CFRP is used, either as standard equipment or in aftermarket parts, in high-performance radio-controlled vehicles and aircraft, i.a. for the main rotor blades of radio controlled helicopters—which should be light and stiff to perform 3D maneuvers.
    Fire resistance of polymers or thermoset composites is significantly improved if a thin layer of carbon fibers is molded near the surface—dense, compact layer of carbon fibers efficiently reflects heat.[3].
    Covers of Thinkpads laptops from Lenovo/IBM and Sony use this technology.
    Carbon fiber is a popular material to form the handles of high-end knives.
    This material is used when manufacturing squash, tennis and badminton racquets.
    Carbon-Graphite spars are used on the frames of high-end Sport kites
    In 2006 Kookaburra Sport introduced cricket bats with a thin carbon fibre layer on the back which were endorsed and used in competitive matches by high-profile players including Ricky Ponting and Michael Hussey. The carbon fibre was claimed to increase the durability of the bats, however they were banned from all first-class matches by the ICC in 2007.[4]
    [edit] End of useful life/recycling

    Carbon fiber-reinforced polymers (CFRPs) have an almost infinite service lifetime when protected from the sun, and, unlike steel alloys, have no endurance limit when exposed to cyclic loading. When it is time to decommission CFRPs, they cannot be melted down in air like many metals. When free of vinyl (PVC or polyvinyl chloride) and other halogenated polymers, CFRPs can be thermally decomposed via thermal depolymerization in an oxygen-free environment. This can be accomplished in a refinery in a one-step process. Capture and reuse of the carbon and monomers is then possible. CFRPs can also be milled or shredded at low temperature to reclaim the carbon fiber, however this process shortens the fibers dramatically. Just as with downcycled paper, the shortened fibers cause the recycled material to be weaker than the original material. There are still many industrial applications that do not need the strength of full-length carbon fiber reinforcement. For example, chopped reclaimed carbon fiber can be used in consumer electronics, such as laptops. It provides excellent reinforcement of the polymers used even if it lacks the strength-to-weight ratio of an aerospace component.
     
  16. so in the first vid they were usin a peel and stick carbon fiber:confused:awesome shit.....is kevlar just a stronger form of carbon fiber..maybe not stronger..maybe bit more flexible t stop projectiles with a little give..understand a knive is more effective vs. kevlar than a bullet...is cost the limiting factor at this point:smoke:...awesome post:smoke:
     
  17. yes. fiberglass is cheaper. carbon fiber and kevlar are just harder to get and more expensive, but they work the same way as fiberglass. all are used with epoxy-resin as a matrix.

    Kevlar

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    Kevlar [​IMG] Identifiers CAS number 24938-64-5 Properties Molecular formula [-CO-C6H4-CO-NH-C6H4-NH-]n [​IMG](what is this?) (verify)
    Except where noted otherwise, data are given for materials in their standard state (at 25 C, 100 kPa) Infobox references [​IMG] [​IMG]
    Molecular structure of Kevlar: bold represents a monomer unit, dashed lines indicate hydrogen bonds.


    Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed at DuPont in 1965,[1][2][3] this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires. Typically it is spun into ropes or fabric sheets that can be used as such or as an ingredient in composite material components.
    Currently, Kevlar has many applications, ranging from bicycle tires and racing sails to body armor because of its high tensile strength-to-weight ratio; by this measure it is 5 times stronger than steel on an equal weight basis.[2] When used as a woven material, it is suitable for mooring lines and other underwater applications.
    A similar fiber called Twaron with roughly the same chemical structure was developed by Akzo in the 1970s; commercial production started in 1986, and Twaron is now manufactured by Teijin.[4][5]
    Contents

    [hide]

    [edit] History

    Poly-paraphenylene terephthalamide - branded Kevlar - was invented by Stephanie Kwolek while working for DuPont.[6] In anticipation of a gas shortage, in 1964 her group began searching for a new lightweight strong fiber to use for light but strong tires.[6] The polymers she had been working with at the time, poly-p-Phenylene-terephthalate and polybenzamide,[7] formed liquid crystal while in solution, something unique to those polymers at the time.[6] The solution was "cloudy, opalescent upon being stirred, and of low viscosity" and usually was thrown away. However, Kwolek persuaded the technician, Charles Smullen, who ran the "spinneret" to test her solution, and was amazed to find that the fiber did not break, unlike nylon. Both her supervisor and laboratory director understood the significance of her discovery and a new field of polymer chemistry quickly arose. By 1971, modern Kevlar was introduced.[6] However, Kwolek was not very involved in developing the applications of Kevlar.[8]
    [edit] Production

    Kevlar is synthesized in solution from the monomers 1,4-phenylene-diamine (para-phenylenediamine) and terephthaloyl chloride in a condensation reaction yielding hydrochloric acid as a byproduct. The result has liquid-crystalline behavior, and mechanical drawing orients the polymer chains in the fiber's direction. Hexamethylphosphoramide (HMPA) was the solvent initially used for the polymerization, but for safety reasons, DuPont replaced it by a solution of N-methyl-pyrrolidone and calcium chloride. As this process was patented by Akzo (see above) in the production of Twaron, a patent war ensued.[9]
    [​IMG]

    Kevlar (poly paraphenylene terephthalamide) production is expensive because of the difficulties arising from using concentrated sulfuric acid, needed to keep the water-insoluble polymer in solution during its synthesis and spinning.[citation needed]
    Several grades of Kevlar are available:

    1. Kevlar K-29 – in industrial applications, such as cables, asbestos replacement, brake linings, and body/vehicle armor.
    2. Kevlar K49 – high modulus used in cable and rope products.
    3. Kevlar K100 – colored version of Kevlar
    4. Kevlar K119 – higher-elongation, flexible and more fatique resistant.
    5. Kevlar K129 – higher tenacity for ballistic applications.
    6. Kevlar AP – has 15% higher tenacity than K-29.[10]
    7. Kevlar XP – lighter weight resin and KM2 plus fiber combination.[11]
    8. Kevlar KM2 – enhanced ballistic resistance for armor applications[12]
    The ultraviolet component of sunlight degrades and decomposes Kevlar, a problem known as UV degradation, and so it is rarely used outdoors without protection against sunlight.[citation needed]
    [edit] Structure and properties

    When Kevlar is spun, the resulting fiber has a tensile strength of about 3,620 MPa,[13] and a relative density of 1.44. The polymer owes its high strength to the many inter-chain bonds. These inter-molecular hydrogen bonds form between the carbonyl groups and NH centers. Additional strength is derived from aromatic stacking interactions between adjacent strands. These interactions have a greater influence on Kevlar than the van der Waals interactions and chain length that typically influence the properties of other synthetic polymers and fibers such as Dyneema. The presence of salts and certain other impurities, especially calcium, could interfere with the strand interactions and caution is used to avoid inclusion in its production. Kevlar's structure consists of relatively rigid molecules which tend to form mostly planar sheet-like structures rather like silk protein.[14]
    [edit] Thermal properties

    Kevlar maintains its strength and resilience down to cryogenic temperatures (−196 C); in fact, it is slightly stronger at low temperatures. At higher temperatures the tensile strength is immediately reduced by about 10–20%, and after some hours the strength progressively reduces further. For example at 160 C (320 F) about 10% reduction in strength occurs after 500 hours. At 260 C (500 F) 50% strength reduction occurs after 70 hours.[15]
    [edit] Applications

    [edit] Protection

    [edit] Armor

    Kevlar is a well-known component of personal armor such as combat helmets, Ballistic face masks, and Ballistic vests. The PASGT helmet and vest used by United States military forces since the early 1980s both have Kevlar as a key component, as do their replacements. Other military uses include bulletproof facemasks used by sentries and spall liners used to protect the crews of armoured fighting vehicles. Related civilian applications include Emergency Service's protection gear if it involves high heat (e.g., tackling a fire), and Kevlar body armor such as vests for police officers, security, and SWAT.[citation needed]
    [edit] Personal protection

    Kevlar is used to manufacture gloves, sleeves, jackets, chaps and other articles of clothing[16] designed to protect users from cuts, abrasions and heat. Kevlar based protective gear is often considerably lighter and thinner than equivalent gear made of more traditional materials.[citation needed]
    [edit] Sports equipment

    [​IMG] [​IMG]
    Kevlar is a very popular material for racing canoes.


    It is used as an inner lining for some bicycle tires to prevent punctures, and due to its excellent heat resistance, is used for fire poi wicks. In table tennis, plies of Kevlar are added to custom ply blades, or paddles, in order to increase bounce and reduce weight. It is used for motorcycle safety clothing, especially in the areas featuring padding such as shoulders and elbows. It was also used as speed control patches for certain Soap Shoes models.[citation needed]
    In Kyudo or Japanese archery, it may be used as an alternative to more expensive hemp for bow strings. It is one of the main materials used for paraglider suspension lines.[citation needed]
    It is also used in the laces for the adidas F50 adizero Prime football boot.
    [edit] Music

    [edit] Audio equipment

    Kevlar has also been found to have useful acoustic properties for loudspeaker cones, specifically for bass and midrange drive units.[17]
    [edit] Drumheads

    Kevlar is sometimes used as a material on marching snare drums. It allows for an extremely high amount of tension, resulting in a cleaner sound. There is usually some sort of resin poured onto the kevlar to make the head airtight, and a nylon top layer to provide a flat striking surface. This is one of the primary types of marching snare drum heads. Remo's "Falam Slam" Patch is made with kevlar and is used to reinforce bass drum heads where the beater strikes.[citation needed]
    [edit] Woodwind reeds

    Kevlar is used in the woodwind reeds of Fibracell. The material of these reeds is a composite of aerospace materials designed to duplicate the way nature constructs cane reed. Very stiff but sound absorbing Kevlar fibers are suspended in a lightweight resin formulation.[18]
    [edit] Other uses

    [edit] Rope, cable, sheath

    The fiber is used in woven rope and in cable, where the fibers are kept parallel within a polyethylene sleeve. The cables have been used in suspension bridges such as the bridge at Aberfeldy in Scotland. They have also been used to stabilise cracking concrete cooling towers by circumferential application followed by tensioning to close the cracks. Kevlar is widely used as a protective outer sheath for optical fiber cable, as its strength protects the cable from damage and kinking. When used in this application it is commonly known by the trademarked name parafil.[citation needed]
    [edit] Electricity generation

    Kevlar was used by scientists at Georgia Institute of Technology as a base textile for an experiment in electricity-producing clothing. This was done by weaving zinc oxide nanowires into the fabric. If successful, the new fabric would generate about 80 milliwatts per square meter.[19]
    [edit] Building construction

    A retractable roof of over 60,000 square feet (5,575 square metres) of Kevlar was a key part of the design of Montreal's Olympic stadium for the 1976 Summer Olympics. It was spectacularly unsuccessful, as it was completed ten years late and replaced just ten years later in May 1998 after a series of problems.[20][21]
    [edit] Brakes

    The chopped fiber has been used as a replacement for asbestos in brake pads. Dust produced from asbestos brakes is toxic, while aramids are a benign substitute.[citation needed]
    [edit] Expansion joints and hoses

    Kevlar can be found as a reinforcing layer in rubber bellows expansion joints and rubber hoses, for use in high temperature applications, and for its high strength. It is also found as a braid layer used on the outside of hose assemblies, to add protection against sharp objects.[citation needed]
    [edit] Particle physics experiment

    A thin kevlar window has been used by the NA48 experiment at CERN to separate a vacuum vessel from a vessel at nearly atmospheric pressure, both 192 cm in diameter. The window has provided vacuum tightness combined with reasonably small amount of material (only 0.3% to 0.4% of radiation length).[citation needed]
    [edit] Composite materials

    Aramid fibers are widely used for reinforcing composite materials, often in combination with carbon fiber and glass fiber. The matrix for high performance composites is usually epoxy resin. Typical applications include monocoque bodies for F1 racing cars, helicopter rotor blades, tennis, table tennis, badminton and squash rackets, kayaks, cricket bats, and field hockey, ice hockey and lacrosse sticks.
     
  18. so is the epoxy resin the actual weak point in composites...what ya could do with one of those computer milling machines and a free week end:Dthank god there are still a few sharp minds still out there:smoke:
     

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