Plex) is a transparent plastic that looks very much like glass, but, compared to glass, has more advantages:

• Twice as light in weight;
• Stronger and more impact resistant;
• Possesses the best heat-insulating properties;
• More transparent.

Acrylic has two major shortcomings- it is more expensive and with direct exposure to fire, it begins to melt and burn. Also, when working with it, it is necessary to avoid heating, since acrylic reacts poorly to high temperatures and this can lead to significant stresses in the material, which, in turn, can lead to cracking.

How to cut?

Plexiglas is usually protected by film on both sides. It is recommended to leave the acrylic in protective film throughout the processing process to protect the coating.

There are several ways to cut Plexiglas, but regardless of the method you use, you should always make sure that the cutting tool does not become a source of heat. One way to cut is to use cutting machine preferably with a carbide blade with 10 teeth per inch. Plex can also be cut with milling machine CNR, carbon dioxide (CO2) laser technology or fine supersonic water jet. Please note that the edge finish will differ depending on the cutting method.

Choose a machine blade that is specifically designed for cutting acrylic. The teeth of the blade should be even, thin and evenly distributed at the same height. Make sure the blade is in contact with the material at a constant speed, as changes in speed can cause the edge of the material to melt.

Thin acrylic parts (1/8" ≈ 3mm thick or less) can be cut like glass using an engraving knife, metal scriber, awl, or carving knife, and broken cleanly at the end. Please note that if you need to make a long cut, this method will not work, as it leaves edges that are not flat enough, which are then difficult to glue.

How to drill?

Acrylic lends itself well to drilling, but heat and careless handling of the material during drilling must be avoided. The heat generated by the drill can lead to melting or cracking, and any careless movement of material around the drill can lead to breakage.

Use special ground and polished drill bits designed for acrylic, or adjust the shape of a conventional twist drill to grinding machine so that it can be used for drilling polymer. The shape of the twist drill can be changed by grinding the edges of the drill on both sides so that a scraping action is created when drilling. If the drill bit is properly sharpened and operated at the correct speed, long curly strips will be achieved during the machining process.

Drill speed is also an important factor. Set the drill press to 500 to 1000 rpm. Is always start and finish processing at a slow speed. If you are going to drill multiple holes, let the tool cool down from time to time to avoid heating up the acrylic.

You can put a piece of plywood under the bottom of the acrylic sheet to give the drill more space and not hit the plexiglass when slowing down the tool. To prevent cracking, do not work too close to the edge (1.5 hole diameters from center would be considered too close).

How to handle edges?

Depending on what the product will be used for, what kind of edge finish you want, whether you plan to glue the edges and what type of glue you plan to use, you can determine how well the edges of the plexiglass need to be processed. On the initial stage working with acrylic glass, you must remember that choosing the right blade for cutting can greatly minimize the need for future edge processing.

How to glue?

Solvent-based adhesives are recommended to achieve strong bonds and transparent seams. When working with this adhesive, make sure the area is well ventilated and away from sources of heat and fire. Also, follow the manufacturer's instructions and don't forget to wear protective goggles and overalls.

The capillary method of gluing acrylic is the most popular. To achieve a perfect bond, check that the surfaces of the elements are well connected and that they are flat, straight and clean. Connect the parts using adhesive tape or a clip, and keep the joint horizontal so that the adhesive does not run out.

Gently apply glue along the edges. When gluing edges that form a square corner, apply glue to the inside edge. When gluing flat edges, apply glue to both sides if possible.

For best results use a bottle with a needle applicator. It takes at least 30 minutes for the parts to stick together, but to achieve maximum strength - from 24 to 48 hours.

Plexiglas has many uses... including your next piece!

Acrylic can be purchased in sheets, tubes or rods in various thicknesses and is a popular material for windows, aquariums, shower doors, skylights, picture frames and more. Some brands, such as Acrylite and Lucite, produce acrylic in different colors, textures and for different purposes. Once you understand the basics of working with acrylic, you can make whatever you want out of it!

cutting

It is convenient to cut sheets of plexiglass with the help of special knife cutter made from a piece of old hacksaw blade. cutting edge grind on a normal emery. Wrap the handle of the cutter with an insulated wire MGShV with a cross section of 0.5-0.75 mm 2, and then with an insulating tape.

Place a sheet of organic glass on a flat surface, such as a table, and, having attached a ruler to the glass, draw the cutter several times over the glass. Then, having cut through the glass at least one third of the thickness, move the sheet to the edge of the table along the cut line and, holding one edge with your left hand, with a sharp and strong movement right hand break off.

Figured details from plexiglass can be successfully cut out with a jigsaw, it is only necessary to remember that at a high cutting speed, the glass begins to melt and can “tightly” grab the file. Therefore, cool it with water from time to time.

The low melting point makes it possible to cut organic glass with a thermal cutter, which can be made from a jigsaw by inserting a nichrome thread instead of a file, after isolating the jigsaw sponges with pieces of asbestos or a fluoroplastic film. Connect the nichrome thread with flexible wires to the LATR and, by applying voltage, heat it up to the melting point of the plexiglass.

drilling

When drilling plexiglass, it must be borne in mind that the drill is tightened and the material jams. Therefore, conventional drills must be reground according to the following parameters: pointing angle - 70˚ back sharpening angle from 4˚ to 8˚, flute angle - 17˚. Only for drilling small holes with a diameter of up to 5 mm, conventional standard drills can be used. And to prevent the material from heating up and melting, add water instead of drilling.

Gluing

Very often, a complex part from a material such as plexiglass is easier to make from separate fragments by gluing them together. Connections can be different - overlap, mustache, butt, tongue and groove. Clamp the glued products with a clamp or tie them with a flexible bandage and hold in this state for about three hours until the glue dries completely. For gluing plexiglass, the most widely used glue is prepared according to the following recipe: in 100 g of dichloroethane, with vigorous stirring, dissolve 2-5 g of chips or sawdust of plexiglass with room temperature. The dissolution is very slow, so the preparation of the glue will take two to three days. Attention! All operations with dichloroethane must be carried out in a well-ventilated area or outdoors, as its fumes are toxic.

You can bend and give the necessary shape to a sheet of plexiglass by heating it over an electric stove or a soldering iron tip. After cooling, the material will take the desired shape.

Coloring

Use a sharp knife or file to cut the plexiglass filings, and then dissolve them in strong vinegar essence. At the same time, take one part of sawdust for six parts of the essence. When the sawdust dissolves, add ballpoint pen paste to the solution. The color of the varnish and its saturation depend on its color and quantity. It is necessary to use varnish very carefully, since the vinegar essence that is part of it can cause burns on the hands and ruin clothes. As a dye, zaponlak of red, green, blue, violet and other colors can also be successfully used. After pouring the varnish into a glass or enameled cuvette, immerse the part in it. Exposure ranges from a few seconds to 15 minutes, it all depends on the desired shade. To obtain a relatively saturated tone of the dye, dipping can be repeated several times, allowing the varnish to dry each time.

The zaponlaks are perfectly mixed with each other, this circumstance can be used to obtain various colors and shades. Since the lacquer slightly dissolves the plexiglass, the coloration is very durable and the surface of the part can be sanded and polished.

Aniline dyes also give good results. To do this, dissolve 0.5 g of the dye in methyl alcohol. Pour the solution into a flat enameled cuvette and place on water bath. Since the boiling point of alcohol is lower than the boiling point of water, the dye soon boils. Preheat the plexiglass to be painted in hot water and then dip into the dye bath. Due to diffusion, the dye penetrates the plexiglass and will adhere well to the surface.

Organic glass is called glass only formally. In fact, plexiglass (or polymethyl methacrylate, PMMA for short) is synthetic material, which is a thermoplastic transparent plastic. Chemical composition standard plexiglass of any production is the same. In case it is necessary to obtain glass with different

Specific - heat-resistant, light-scattering, light-transmitting, noise-protective, UV-protective, heat-resistant and other properties, then in the process of obtaining sheet material its structure can be changed or appropriate components can be added to it to provide a set of necessary characteristics.

According to the production method, cast and extruded organic glasses can be distinguished. Extruded plexiglass is produced by continuously passing the molten mass of granulated PMMA through a slotted die, followed by cooling and cutting to specified dimensions. Cast plexiglass is produced by pouring MMA monomer between two flat glasses with further polymerization to a solid state.
Compared to ordinary glass, organic glass has several advantages:

• with the same thickness, it is 2-2.5 times lighter than ordinary glass;

• when exposed to a relatively low temperature, it melts, which allows you to give products from it various forms;
• possesses while maintaining original color, high light transmission (92%), which does not change over time;
• impact resistance is 5 times greater than ordinary glass;
• it is easy to work with it not only with the help of machines, but also manually. This does not require special tools;
• it is cut, drilled, turned, glued just as easily as ordinary plastic.

Thanks to these qualities, it is possible to produce various works with plexiglass at home: both in the manufacture of products and parts necessary for everyday life, and in arts and crafts.

Along with the advantages, organic glass also has its disadvantages:

• it is quite sensitive to scratching and other superficial damage;
• is a flammable material (ignition temperature - 260 ° C).

Thus, organic glass cannot completely replace ordinary glass, each of them has its own scope.

Surface preparation of organic glass for processing

Before work, organic glass must first be cleaned. In the event that the glass surface is simply dirty, it must be wiped soft cloth or a cotton swab dipped in warm water. If a sheet of plexiglass small size heavily soiled, then it can be prepared for work by putting it in a bath and thoroughly washing it with a rag under a stream warm water. It is not recommended to use synthetic material for cleaning organic glass - if you rub the surface of the glass with it quite hard, it will become dull. Moreover, you can not use any abrasive substances - they will scratch the glass, and it will lose its original transparency.

Clean glass must be wiped dry. If you just leave it to dry, then after drying, stains will remain on the surface. This operation best done with a slightly damp cloth, you can also use a special polishing paste (it additionally helps to remove from the surface small scratches). For this on glass thin layer a liquid paste is applied, after which it is polished with a cloth in a circular motion. If there are greasy and oil stains on the surface, it will not be enough just to wash the glass even warm water with soap. It needs to be degreased with gasoline.

When preparing plexiglass for work, it must be taken into account that the friction of the fabric on dry glass leads to its electrification. Dust immediately sticks to the electrified surface, and these particles also cause micro-scratches and make the glass matte. The use of aggressive liquids (acetone and other solvents) is unacceptable - this will render the glass unusable.

Prepared organic glass can be subjected to almost any processing: cutting, drilling, threading, milling, grinding, polishing, bending, gluing, annealing, painting and metallization.

A band saw is more suitable for cutting blanks before shaping, since with such cutting there is no need to obtain a clear cut (for cutting cast acrylic, they use band saw with a rotation speed of 700-800 m/min.). To get a clear and smooth surface when cutting complex shapes, it is recommended to use a cutter. Circular saws allow you to make straight, accurate cuts with a clear cut (when cutting cast acrylic, they use circular saw with carbide-reinforced teeth with a rotation speed of 800-1200 m/min). When carrying out small work, saws with a blade for light metals can be used.

For more technological cutting, it is preferable to use high-speed equipment. With a high cutting speed and a minimum feed rate, a quality edge can be obtained (when cutting extruded plexiglass using high-speed circular saws the recommended disk rotation speed is 4000 rpm. (For processing it is necessary to use blades with a diameter of 250 mm, made of high-speed steel or reinforced with hard alloy. To avoid deformation, the teeth of the saws must be unset). Cutting with a laser beam has a number of advantages: exceptional cutting accuracy, low waste, cuts High Quality requiring minor sanding.

However, this method contributes to the appearance of a high internal stress of the material, and further bonding of such surfaces is not recommended. Cast plexiglass is easy to machine, but due to low thermal conductivity it quickly heats up in the cutting zone. Therefore, processing should be carried out at the smallest depth of the cut layer, but with high cutting speeds.

Attention! To avoid scratches during storage or machining, do not remove the protective film or paper cover.

Plexiglas drilling

Drilling of extruded plexiglass is carried out using a stationary or mobile drilling machine using special drills for light metals made of high-speed steel with increased productivity, specially sharpened for drilling extruded plexiglass. Edges need to be smooth. drilled hole to avoid the formation of cracks. In the case of deep drilling, it is recommended to raise the drill frequently to extract the chips and limit the heating of the material. When drilling molded plexiglass, any metal screw drills. Drill diameter correction factor +0.05 mm relative to hole diameter. Cooling required to avoid internal stresses when drilling cutting tool and material with coolant lubricants or compressed air.

Cold bending plexiglass

Plexiglas, both cast and extruded, can be easily cold-bent, but the minimum bending radius must be observed in order not to subject the boards to undue stress. The minimum value of the bending radius should be 230 times the thickness of the plastic.

Plexiglas engraving

In most cases, it is produced with the help of rippers mounted on pantographs and equipped with cutters of small diameter (2-6 mm) of various profiles. Laser cutting machines can also be used, which allow engraving by limiting the depth of the laser beam.

Plexiglas grinding

Rough surfaces or surfaces with defects such as scratches are sanded wet sandpaper from fine corundum. After rough polishing, the surface should be treated by special means. (polishing pastes such as VIAM, tripoli, crocus, dispersed in wax). All operations are carried out either manually or on a polishing machine.

Plexiglas polishing

Cut edges and matte surface can be polished with high quality mechanically with diamond cutters. However, if this is not possible, for example, the cut is curved, then flame polishing is recommended. This method consists in processing products with a clean "hard" flame of high temperature, but some precautions should be observed. So, for example, the surface to be sanded must be absolutely clean, and in addition, this method contributes to the occurrence of significant stresses, which must be removed by annealing before gluing or applying paint.

Welding and gluing plexiglass

1. In the case of cast plexiglass, it is recommended to use (as for extruded plexiglass) "related" adhesives, which allows you to achieve the most durable connection and its weather resistance. To obtain transparent, colorless seams when gluing with an overlap or butt with a one-sided overlay, it is preferable to use an SMM adhesive based on polymethyl methacrylate.

Before gluing, molded plexiglass parts must be annealed to relieve internal stresses. The recommended annealing temperature is 65-80C depending on the glass softening temperature (90-120C), after which natural cooling is preferred.

Welding is also used to obtain blanks for molding non-standard products, for attaching linings and forming thickenings. Welding of cast plexiglass is carried out at more than high temperatures(up to 300 0 C). The finished part after mechanical processing of the seam is subjected to heat treatment to relieve internal stresses.

2. Sheets of extruded plexiglass can be bonded to themselves and to other materials, resulting in a high-strength and durable seam. Before gluing, it is desirable to carry out heat treatment.

Materials for gluing extruded plexiglass:

Film type glue: solution of polymethyl methacrylate in a volatile solvent;

Polymerizable adhesive type: PMMA syrup with dimethylaniline (SMM), to which a polymerization initiator (benzoyl peroxide) is added at the time of bonding;

Other types of glue: epoxy, polyester, polyurethane, etc. grades AK-90, MP-88 (81), BF-2 (4.6);

Solvents: dichloroethane, methylene chloride.

After drying and hardening of the adhesive at room temperature, it is recommended to anneal for 2-5 hours at a temperature of 60C.

Welding is carried out by several methods:

induction;

radiation;

ultrasonic soldering;

Vibrations;

Hot gas.

Hot forming plexiglass

This type of processing allows you to give the material a variety of shapes. If the resulting part does not match the desired shape, it can be reheated and then corrected. Cast acrylic has shape memory and is able to easily return to its original position when reheated. With extrusion, this is possible only if the material has not been stretched. The protective film must be removed from the cast plastic before heating and can be left on the extrusion. Acrylic must be pre-hot dried before shaping to avoid bubble formation in the finished product.

The need for drying arises from the fact that during storage or transportation, a small amount of moisture may penetrate the material. Drying is carried out either in convection drying chamber with hot air circulation (at a temperature of 75-80 C for 1-2 hours for each mm of thickness. As a rule, at great content 24 hours of drying is sufficient), or by means of infrared radiation at a temperature of 75 to 80 ° C for 1-2 hours for each mm of thickness. To heat cast plexiglass before molding, equipment is used that creates a uniform temperature field with a difference in the plane and thickness of the sheet no more than - + 3 C. Cast glass is heated 3-4 min/mm thickness to a temperature of 165-190°C.

Cast plexiglass softens quickly when heated, but its strength decreases slightly in comparison with extrusion. Cast and extruded acrylic react differently to heat. For cast, uniform shrinkage of a maximum of 2% is possible, the same in all directions (the thickness of the sheet increases accordingly). For extrusion - from 3 to 6% in the direction of extrusion and 1-2% in the transverse direction (for a sheet of 2mx3m, the direction of extrusion is the side of 3m). Cast acrylic easily tolerates heating inhomogeneities of 10-15 ° C (overheated cast acrylic, unlike extrusion, does not crack or break during deformation), in the case of extrusion, the difference in heating temperature can lead to significant stresses in the material.

2. The behavior of these materials during hot forming is also different. To deform cast acrylic, significant pressure must be applied, while extrusion is molded easily and without special efforts(recommended temperature interval- 160-170°С; heating time - 3 minutes per 1 mm of material thickness). Forms (matrices and punches) are made from various materials: wood, plaster, aluminum, steel. Hot forming can be done simple ways, for example, by placing plastic after heating on a convex or concave shape, where it takes on its shape under its own weight.

Molding can also be carried out by free drawing in a vacuum-tight chamber and free blowing with compressed air, both with and without molds. If it is necessary to bend a flat sheet in a straight line, then it is sufficient to conduct local heating of the plastic along the bending axis using one or more straight lines. heating elements, for example, a nichrome string. Attention! During hot processing and/or molding protective covering must be removed and cleaned thoroughly, as adhesive residue or protective film softening the sheet can damage its surface.

3. To avoid the occurrence of internal stress, the cooling should be as long and uniform as possible. For the best preservation of the imprinted form and in order to avoid deformation, the product must be left on the matrix until it cools down to a temperature of 60-70°C. Molded products before their interaction with solvents, paint or self-adhesive film must be subjected to thermal conditioning in order to reduce stress.

Glass, but not broken... Because it is not ordinary, but organic, or, as it is also called, plexiglass. This is wonderful material. It is easily processed. It can be sawn, planed, sharpened with an ordinary cutter on lathe, extrude, blow... Parts made of this material stick together easily and firmly. So much so that even the gluing lines are transparent, almost invisible.

However, this material has its own characteristics, which are very useful to know when processing it. Let's talk about them.

Cutting plexiglass.

Sheet material, of course, can be sawn with a hacksaw, but this is too troublesome. And the seam is of poor quality. To improve the situation, they use special home-made large-toothed hacksaw blades. But it is best to use cutters. A cutter is essentially a saw with only one tooth (Figure 1). They sharpen it on emery from a piece of a hacksaw (steel P9, P18) and take it into the handle by hand.

A steel ruler is placed on a sheet of plexiglass and the cutter is passed several times until the material is cut halfway. Then it is simply broken (Fig. 2, 3), and the edge of the fracture is cleaned with an ordinary joiner's jointer. Very convenient for this purpose is a homemade jointer, consisting of a rasp with two handles (Fig. 4). Or you can simply - a cycle made from a piece of an old cutter with an even rectangular edge. It should be held in the hand as shown in Figure 5.

There is another scraping technique - using a piece of ordinary glass. As shown in Figure 6, the plane of the glass almost touches the processed edge - in this case, the surface is completely transparent.

Plexiglas can also be cut on a circular saw with conventional cutters for metal with a thickness of 0.5-1 mm. True, during operation they quickly heat up, the material begins to smoke, and the treated surface turns out to be rough, foamy. For this reason, getting a straight cut is very difficult. But if the cutter is cooled, this will not happen. Fit for it regular bottle, placing it on one side of the cutter and filling it with water. Water is supplied through a plastic hose with a diameter of 2-3 mm. 0.5 liters is enough for an hour of work. During breaks, the hose can be clamped with a clothespin. Water cooling increases productivity by 2-3 times. But most importantly, a very smooth translucent surface is obtained. If the cutter is polished and the teeth sharpened using a whetstone, then you can get completely transparent.

Plexiglas polishing.

It is sometimes impossible to completely do without this operation. But before proceeding with it, the surface is well prepared - all irregularities are ground with fine sandpaper. Do it better with water.

Hand polishing is done with a piece of flannel or old wool blanket pre-lubricated with polishing paste. Finish polishing with a piece of the same cloth, but completely clean or oiled.

The work will go faster if you use a polishing wheel mounted on the shaft of a conventional emery sharpener. In the simplest case, this can be a package of circles made of baize, felt or cloth, sandwiched between two washers.

For polishing products close in shape to spherical, it is necessary to use a soft circle, for flatter ones - a hard one. And it's better to have two of them. One, lubricated with polishing paste, to polish, the other, clean - to bring the final gloss. If the linear speed of the polishing wheel is too high - about 10 m / s, then local overheating of the surface of the product is possible. The material will bubble, and this is a hard-to-fix defect. Make sure this doesn't happen.

Plexiglas molding.

At a temperature of 110-135 ° C, plexiglass becomes plastic and bends under own weight. But if the temperature is slightly lower - the material is brittle, slightly higher - bubbles appear that degrade the quality. Therefore, heating the plexiglass on a baking sheet in the oven gas stove follow the readings of the thermometer. Its accuracy is sometimes low. Check on a test piece of material at which mark the first bubbles will appear.

For molding, it is enough to have a wooden punch and a plywood (10 mm) matrix (Fig. 8). The hole of the matrix must follow the contour of the product in plan with an allowance for the thickness of the material being processed. So that there are no traces of the wood texture on the product, grease the punch and the edges of the matrix with casein glue. When the glue dries, clean the entire surface with sandpaper.

Forming is best done with two people on the floor, laying a piece of plywood so as not to spoil the linoleum or parquet. A person working with heated plexiglass should put on warm woolen or cotton gloves on his hands, and canvas mittens on top. We remind you: no synthetic products are applicable here - they melt easily and can cause severe burns.

When a piece of plexiglass is hot, it is quickly removed from the oven and placed on the matrix. Your assistant, without delay, takes the punch, presses lightly on it, fixing it in the desired position, and then stands on it with his feet. After about 5-10 minutes, the finished part can be removed, excess material removed and further processing can begin.

In cases where it is necessary to make a part in the form of a hemisphere, instead of a punch, you can use compressed air(Fig. 9). The stamp in this case is a matrix 1 and a base 2 with a fitting 3. A workpiece is laid between them. Plexiglas plate 4 is installed between the matrix and the base and is tightened with screws 5. The stamp is heated in an oven until the plexiglass softens. Then it is quickly removed, a hose is put on the fitting and air is supplied under pressure. For this, a car pump is quite suitable.

The easiest way to get a cylinder from a flat sheet is to use a pipe segment as a shaping element (Fig. 10). Taking the heated billet by the wire ring (its shape is shown in Figure 11), we draw it into the pipe hole and leave it there until it cools completely.

How to glue plexiglass.

Plexiglas is most often glued with dichloroethane - either pure or with chips dissolved in it. But dichloroethane is poison. Therefore, you can work with it only in a room with good ventilation. And, of course, that there are no food products nearby. The surfaces to be glued are lubricated with dichloroethane and compressed so that air bubbles are squeezed out. The gluing site sets within a few minutes.

Plexiglas coloring.

In order for the product to be painted evenly, it is pre-polished (if required), scratches and chips are removed. Then a dye solution is prepared: for every 100 weight parts of alcohol (denatured alcohol or alcohol solvent), 0.08 - 0.15 weight parts of the dye are taken. You can also use alcohol stains for wood. They contain alcohol and dye. Their color is changed by adding other alcohol-soluble dry dyes.

Here are some dyes that dissolve in alcohol: Sudan red, Sudan orange, alcohol-soluble nigrosine (black), a mixture of chrysoidin and rhodamine (bright red), rhodamine (crimson), and others of a similar type. A suitable dye is ballpoint pen paste. It contains 5 to 25 percent pure, high quality permanent color.

The prepared product, cleaned of dirt and grease stains, is immersed for 5-20 minutes in a dye solution. The dye, in turn, is placed in a pan with hot water heated in advance. It is impossible to heat the dye solution directly on fire: it is flammable. The color intensity of plexiglass, the depth of dye penetration into it largely depend on how long the product is kept in solution, and on the amount of dye.

After holding the product in a hot solution, it is transferred to a vessel with cold water. After cooling, wipe dry with filter or blotting paper, a soft cloth, and then, to add shine, lightly polish with chamois, soft felt or cloth. It is even better to polish with special polishing pastes sold in stores, for example, GOI paste No. 5, thin. LIK paste is especially good for polishing plexiglass and other plastics.

You can make your own polishing paste. In molten paraffin (melting point 52 degrees) is introduced, thoroughly mixing, pounded and sifted through fine sieve chromium oxide (weight ratio of paraffin and chromium oxide 1:1). Chromium oxide is evenly distributed in paraffin. When the paraffin hardens, a hard, greasy to the touch paste is formed, evenly colored green.