Glass, but does not break... Because it is not ordinary, but organic, or, as it is also called, plexiglass. This is wonderful material. It is easy to process. It can be sawed, planed, sharpened with an ordinary cutter lathe, squeeze, blow... Parts made of this material are easily and firmly glued together. So much so that even the gluing lines turn out transparent, almost imperceptible.
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 sawed with a hacksaw, but this is too troublesome. And the seam is of poor quality. To improve the situation, they use special homemade 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 using sandpaper from a piece of a hacksaw (steel P9, P18) and take it into the handle along the hand.
Place a steel ruler on the plexiglass sheet and run the cutter several times until the material is cut halfway through. Then they simply break it (Fig. 2, 3), and the edge of the fracture is cleaned with an ordinary joiner's jointer. A homemade jointer consisting of a rasp with two handles is very convenient for this purpose (Fig. 4). Or you can simply use a cycle made from a piece old cutter with a smooth rectangular edge. You should hold it in your 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 edge being processed - in this case, the surface is completely transparent.
Plexiglass can also be cut on a circular saw with ordinary 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 and foamy. For this reason, it is very difficult to obtain a straight cut. But if the cutter is cooled, this will not happen. Adapt for this a regular bottle, placing it on one side of the cutter and filling it with water. Supply water through a plastic hose with a diameter of 2-3 mm. 0.5 l 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, the result is a very smooth translucent surface. If you polish the cutter and sharpen the teeth using a whetstone, you can get a completely transparent one.
Polishing plexiglass.
It is sometimes impossible to completely avoid this operation. But before you start, the surface is well prepared - sanded with fine sandpaper all the irregularities. It is better to do this with water.
Hand polishing is done with a piece of flannel or an old woolen 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 regular emery sharpener. In the simplest case, it can be a package of circles made of flannel, felt or cloth, sandwiched between two washers.
To polish products close to spherical in shape, you need to use a soft wheel, for flatter ones - a hard one. And it's better to have two of them. Alone, lubricated polishing paste, carry out polishing, others, clean ones - bring the final gloss. If linear speed 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 difficult defect to correct. Make sure this doesn't happen.
Molding of plexiglass.
At a temperature of 110-135°C, plexiglass becomes plastic and bends under its own weight. But if the temperature is a little lower, the material is fragile; a little higher, bubbles appear, deteriorating the quality. Therefore, heating plexiglass on a baking sheet in the oven gas stove, follow the thermometer readings. Its accuracy is sometimes low. Check on a test piece of material at which mark the first bubbles appear.
For molding, it is enough to have a wooden punch and a plywood (10 mm) matrix (Fig. 8). The hole in the matrix must follow the contour of the product in plan with an allowance for the thickness of the material being processed. To prevent wood grain marks from remaining on the product, lubricate the punch and the edges of the matrix with casein glue. When the glue dries, sand the entire surface.
Molding is best done by two people on the floor, laying a piece of plywood so as not to spoil the linoleum or parquet. Anyone working with heated plexiglass should put on warm woolen or cotton gloves and canvas mittens on top. We remind you: no synthetic products are applicable here - they melt easily and can cause severe burns.
When the piece of plexiglass warms up, it is quickly removed from the oven and placed on the matrix. Your assistant, without hesitation, 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 produce a part in the form of a hemisphere, compressed air can be used instead of a punch (Fig. 9). The stamp in this case consists of a matrix 1 and a base 2 with a fitting 3. A workpiece is placed between them. Plexiglas plate 4 is installed between the matrix and the base and tightened with screws 5. The stamp is heated in the oven until the plexiglass softens. Then it is quickly removed, a hose is put on the fitting and air is supplied under pressure. A car pump is quite suitable for this.
The easiest way to obtain a cylinder from a flat sheet is to use a piece of pipe as a forming element (Fig. 10). Taking the heated workpiece by the wire ring (its shape is shown in Figure 11), we pull 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 shavings dissolved in it. But dichloroethane is poison. Therefore, you can only work with it in a room with good ventilation. And, of course, make sure 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 area sets within a few minutes.
Painting plexiglass.
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 parts by weight of alcohol (denatured alcohol or alcohol solvent), 0.08 - 0.15 parts by weight of dye is 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 nigrosin (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 from 5 to 25 percent pure, high-quality permanent dye.
The prepared product, cleaned of dirt and grease stains, is immersed in the dye solution for 5-20 minutes. The dye, in turn, is placed in a pan with hot water, heated in advance. You cannot heat the dye solution directly over a fire: it is flammable. The intensity of the color of plexiglass and the depth of penetration of the dye into it largely depend on how long the product is kept in the 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 suede, soft felt or cloth. It is even better to polish with special polishing pastes sold in stores, for example, fine paste No. 5 GOI. LIK paste is especially good for polishing plexiglass and other plastics.
You can make your own polishing paste. Into the molten paraffin (melting point 52 degrees) add, thoroughly mixing, chromium oxide, crushed and sifted through a fine sieve (the ratio of the weight parts of paraffin and chromium oxide is 1:1). Chromium oxide is evenly distributed in paraffin. When the paraffin hardens, a hard, greasy-to-touch paste is formed, uniformly colored green.
Basic techniques for working with organic glass
Processing organic glass is simpler and easier than conventional glass. Plexiglas has the following performance characteristics.
1. When exposed to a relatively low temperature, it melts, which makes it possible to give products made from it various shapes.
2. It is easy to work with it not only using machines, but also manually. No special tool is required.
3. It (like ordinary plastic) is cut, drilled, turned, glued, etc.
These qualities of plexiglass are widely used for various works at home, both in the manufacture of products and parts necessary for everyday life, and for arts and crafts, including stained glass.
Thus, organic glass has some advantages over ordinary glass. However, it cannot completely replace it. Each of them has its own area of application. In this case, of course, you should not replace the broken window glass with a sheet of plexiglass of the same size.
Preparing the surface of organic glass for processing
Before use, organic glass must first be cleaned.
If the surface of the glass is simply dirty, it should be wiped with a soft natural cloth or a cotton swab dipped in warm water.
If a piece of plexiglass small size is heavily contaminated, then it can be prepared for work as follows. You need to carefully put it in the bath and wash it thoroughly with a cloth under running warm water. Then you need to wipe the glass surface dry. This should be done not only because it is necessary to immediately begin work on the glass. If you just leave it to dry, then after drying the surface of the glass will be stained.
When preparing plexiglass for work, you need to take into account that when the fabric rubs against dry glass, the former is charged with static electricity. Dust particles immediately adhere to the electrified surface, and they also cause micro-scratches and give the glass a dull appearance. Therefore, this operation is best carried out by first slightly moistening the wiping material or using a special polishing paste, which can also be used to remove small scratches. To do this on glass thin layer a liquid paste is applied, after which it is sanded with a cloth in a circular motion.
If there are greasy and oil stains on the surface, it will not be enough to simply wash the glass, even warm water with soap. It needs to be degreased with gasoline or kerosene. The use of aggressive liquids (acetone, solvent, etc.) is unacceptable. Otherwise, due to the impact on organic glass, they will render it unusable.
So, the glass is ready for processing.
It is not always possible to have a piece of plexiglass of the required size on hand. A situation often arises when a large sheet needs to be cut. Therefore, first of all, you need to master the method of cutting plexiglass.
Methods for cutting organic glass
You can cut plexiglass in a straight line (like many other materials) with a hacksaw blade inserted into a jigsaw. But it’s easier to use the following frequently used method.
A special knife-cutter is used for this purpose. Its main difference from the usual one is a very small blade and a necessarily pointed end. Usually the tip is made in the form of an angle, but there are other blade shapes.
Cutter knife for cutting organic glass: 1 – wire; 2 – plastic; 3 – hacksaw blade
Such a knife is quite easy to make using a homemade method. The material for it will be the same hacksaw blade. You need a small hacksaw piece that is the right size (approximately 12-15cm) and shaped to fit comfortably in your hand.
When performing work, it is necessary to observe safety precautions. To do this, it is recommended to wrap the fabric well with fabric and carefully bend it on both sides, holding the curved side away from you. In order to prevent damage to the hand, as well as for ease of holding, a wrap is placed on the knife.
As a rule, such a unique handle is made from a suitable wire. Each turn of wire should fit tightly to the other, as well as to the surface of the knife. It is best to first cover the knife at the handle location with insulating tape.
Then they are ground on an emery stone cutting edge– and the knife is ready for cutting.
Plexiglas is cut as follows.
The sheet is placed on a flat horizontal surface without any protruding parts that could scratch it. A ruler is placed on the cutting line. To avoid possible shifting, it should be pressed tightly against the glass, which should also not move during work. To do this, you can use a workbench-clamp, having previously placed some material (plywood, etc.) to protect the glass from deformation.
After this, the edge of the knife is drawn with force along the entire length of the cut. The knife must be held firmly in your hand and under right angle. The first line is carried out especially carefully. In this case, you need to ensure that the knife does not slip off the ruler and spoil the sheet. Then they scratch it as many times as necessary to cut it.
Unlike cutting glass with a jigsaw, the edges of a piece of plexiglass cut with a knife do not need to be filed down.
But in this way it is impossible to cut, for example, a rounded piece of plexiglass or complex shaped parts. Another technology is used here, which is more convenient in this case.
It is based, as already mentioned, on the ability of organic glass to melt quite easily. The essence of the method is to cut through (or rather melt through) glass with a hot wire.
Cutting organic glass: 1 – heated nichrome wire; 2 – plexiglass; 3 – load; 4 – wires to the transformer
For this purpose they can be used additional accessories. You can use a jigsaw instead of a hacksaw blade to pull a thin nichrome wire, having high electrical resistance. A constant or alternating current voltage 3–4 V. Higher voltage is unacceptable, because the plexiglass may catch fire. Naturally, everything else must also be done in compliance with safety standards, that is, the handle of such a cutter must be insulated.
You can cut plexiglass directly with wire. In this case, the edge of the sheet is clamped in a horizontal position with a vice. A wire stretched with a weight easily passes through the glass in any direction.
Drilling organic glass
Drilling plexiglass has its own characteristics. This is due to some viscosity of the material. This operation is quite easy to perform using a conventional drill or vertical drilling machine installed in the workshop. In this case, the following conditions must be observed.
Particular attention should be paid to securing the sheet and small parts cut from a large sheet of plexiglass. This can be done using a vice or clamps. Due to the above-mentioned specifics of the material, the drill may jam during operation.
It often happens that in a hurry, a part is pressed with a hand or foot. Such fastening of glass often leads to injury.
To drill holes up to 5 mm in diameter, you can use standard drill bits and a regular drill. To obtain holes of large diameters, special drills are used: their sharpening angle is 70°, the helix angle of the groove is 17°, and the rear sharpening angle of the drill is 4–8°.
To drill thin plexiglass, a drill tip angle of 60° is required, otherwise the drill may break off glass fragments at the edge of the hole. Accordingly, thick sheets are usually drilled at a tip angle of 90°.
In order not to overheat the edges of the hole in a thick sheet, you need to drill intermittently, periodically removing accumulated chips.
For greater accuracy, it is best to drill through the holes of the jig.
Bonding organic glass
Gluing parts made of plexiglass is a fairly common operation when working with it. In this case, you must first prepare a special glue. It will require the following ingredients:
– dichloroethane – 100 g;
– plexiglass shavings – 3 g.
If there are no chips left from the previous drilling operation or there are too few of them, then it is easy to make them from unnecessary trimmings of plexiglass.
The prepared shavings are poured into a container with dichloroethane made of ordinary glass. With careful but fairly frequent continuous stirring for half an hour, the shavings should dissolve. Then the glue is left for at least 2 days. When infusing, the adhesive mass must be stirred periodically.
The parts to be glued are usually overlapped, butt-jointed, tongue-and-groove, or with an overlay. In this case, the areas to be connected must be well processed and very precisely adjusted to each other.
The glue is carefully applied to both surfaces to be glued using a brush. Moreover, it needs to be driven in one direction. As a result, there should be no air bubbles or accidentally trapped foreign objects on the surface to be glued small items or specks.
When gluing with an overlap, the area to be coated must be at least 4 times the thickness of the sheet. Only in this case the connection will be strong.
Coloring of organic glass
You can paint the surface of plexiglass in several ways listed below.
First way
Tsaponlak is used for painting. First of all, you need to prepare a glass or enamel container of suitable size for immersing the parts. The exposure time in the dye depends on the degree of color saturation you want to achieve. It can range from a few seconds to 15 minutes. If you are not sure about the strength of the tone, you need to test paint a small piece of plexiglass. You can also repaint the glass by first drying it and then immersing it in varnish again.
Second way
The varnish is made at home. To do this you will need plexiglass filings. When there is no sawdust left over from cutting, they can be made using a file.
Sawdust must be dissolved in vinegar essence in a ratio of 1: 6, that is, one part of sawdust to 6 parts of essence. In this case, precautions must be taken to ensure that the resulting solution does not come into contact with the skin. If this does happen, you should immediately rinse the affected area well with water.
Also, you should not allow vinegar essence to get on your clothes and other things - it can ruin them.
After this, a dye is diluted in the resulting solution, which can be ink taken from the refills of ballpoint pens.
Is it true, this method coloring has one drawback: the choice of colors is limited to four: blue, green, red and black.
In addition, for obvious reasons, this method is not entirely suitable for intensive painting of large surfaces. It is best used to add color to plexiglass parts and small products made from it. When painting, they are not immersed in varnish, because it has the ability to dissolve plexiglass. In this regard, the surface is painted with careful application of varnish.
Third way
0.5 g of aniline dye is dissolved in methyl alcohol. The resulting solution then needs to be heated, for which the enamel container with the dye placed in it is placed in another container with water and put on fire. Some time after the water boils, the dye will also boil.
The part to be painted must be prepared while the paint is cooking. It also needs to be heated by briefly immersing it in boiling water. Then the glass is removed and transferred to a container with boiling dye.
This method is convenient because the paint not only forms a surface layer, but its particles penetrate into the plexiglass.
Fourth method
Before painting, the surface of the plexiglass should be especially carefully prepared. To do this, wipe it with gasoline and leave it to dry for a while. The sheet is then dipped into a detergent solution with an average temperature of about 50 °C.
A saturated solution is prepared at the rate of 1 kg washing powder for 1 liter of water. The glass is kept for 10–15 minutes, after which it is washed with cold water and then staining begins immediately.
The dye must be pre-formulated by adding a special dye for acetate silk to benzyl alcohol. To prepare it, take 5 g of dye per 20 g of alcohol. 2–3 g of regular washing powder are also poured into the alcohol solution.
After this, the dye is diluted with hot water to the desired consistency.
Add 1 liter of water to the indicated volume. The prepared glass is immersed in the resulting paint at a temperature of approximately 80 °C. Until the painted plexiglass is removed, the dye must be stirred. Holding time approximately 15 minutes.
If you need to paint a small piece of plexiglass, making it spotted with multi-colored paint stains, you can use the following method.
You need to take nitro paint of several colors. Pour 2-3 tbsp onto a sheet of whatman paper. spoons of the paint whose color will be the background. Randomly drip other paints onto the spread base (about 5 drops of two or three different colors).
After this, you need to bend a sheet of paper in an arc and pour the composition onto the glass. The paint should cover the entire surface. No brush is used here. If there are large drips, the glass should be placed at an angle to remove excess paint. Naturally, it is recommended to choose a place to work in advance and lay something under the plexiglass to be painted.
If the result obtained after drying quickly enough is unsatisfactory, you need to remove the paint using a swab dipped in solvent and repaint the glass again.
Organic glass products can be given White color, etching them with sulfuric acid. When exposed to acid for 1–3 minutes, the plexiglass will acquire a milky white color. If you subject the glass to a longer treatment (up to a maximum of 10 minutes), it will lose its shine and become matte.
After etching the plexiglass, for which it is immersed in a concentrated acid solution, it must be thoroughly rinsed in running water. It is necessary to remove the product painted in this way carefully due to the fact that the surface softens under the influence of sulfuric acid. If at this time the removed plexiglass inadvertently touches something (for example, a container in which the acid was located), then a groove may remain on it. When working with a solution of concentrated sulfuric acid, you must follow safety rules.
It is also possible to apply various inscriptions and drawings to the glass.
Applying inscriptions and drawings on organic glass by etching
First, a sketch of the inscription or drawing is made and transferred to the surface of the plexiglass. It's done like this.
An even layer of paraffin is applied to a sheet of glass heated to a temperature of 60–70 °C. Next, the contours of the drawing or inscription are transferred onto it through carbon paper.
Then the plexiglass is carefully and thoroughly cleaned of paraffin in those places where the drawing or inscription should be etched. Using the point of a needle, a groove is drawn along the marking line in the paraffin (all the way to the surface of the plexiglass), and the unnecessary paraffin is scraped off with the tip of a knife.
Along the edges of the paraffin sheet, sealed walls with a height of about 7 mm are additionally made. Now you can begin the etching process, for which concentrated sulfuric acid is poured into the prepared mold for 5–10 minutes.
After etching is complete, the sulfuric acid is drained and the treated surface is washed repeatedly with cold water.
Then the plexiglass is dried, the paraffin is removed from it, as a result, the desired inscription or milky design remains on the surface.
Applying inscriptions and drawings on organic glass by engraving
Engraving of the surface of plexiglass is carried out using cutters or burs.
The cutter must be high-speed. The rotation speed of a cutter with 10–36 teeth is 2200 rpm.
Engraving is also usually done with burs mounted on the end of a flexible shaft connected to a low-power motor, or a small old dental drill with 6-8 drills is used. In addition, cutters can also be used.
You need to move the bur smoothly, without making much effort. Jerks must not be allowed when drilling. Chips that interfere with engraving should be removed periodically. If necessary, the resulting grooves are cleaned with a needle. The furrow left by the bur should be smooth and not too deep.
Before starting work, it is recommended to practice first on scraps of plexiglass and get used to the work of a bur or cutter. You should also draw an engraving sketch on the plexiglass in advance with a soft pencil.
The often used engraving with cutters on the back of the plexiglass is very beautiful. This allows you to get the effect of a three-dimensional relief pattern. The surface of the product with such an engraving remains smooth, and the image on the inside fascinates with the light refracted in its edges. For greater expressiveness, the milling cuts are painted from the inside in different colors.
Plexiglas stamping
Due to its relative ease, this process is completely doable without any particularly complex special devices.
The matrix (mold) and punch (press) for stamping can be made from hard wood.
A sheet of plexiglass of suitable size is heated in a well-known way - placed in a container of water, which is brought to a boil. Sometimes machine oil is used instead of water. The glass is brought to a state of complete softening.
It is also better to heat the matrix and punch to a temperature of approximately 60–80 °C before use. After this, the heated sheet is placed on the matrix, and a punch is placed on top. To press the glass, the matrix and punch are clamped in a vice. These operations must be performed very carefully and quickly - while the plexiglass is still hot.
When the stamped part has cooled, the vice is unscrewed, the punch and the product itself are removed. The latter is washed from machine oil (if used) in warm water and soap. The excess needs to be cut off. If necessary, treat with fine sandpaper.
The finished product can be polished and painted.
Using approximately the same method, it is possible to make shaped stampings from plexiglass, for example letters, various signs or symbols.
In this case, the matrix is made from aluminum sheet 6–8 mm thick. The desired shape is cut on it using a cutter. It is also better to make the punch from the same material.
For pressing, glass is heated to the desired plastic state. Sometimes a special mass is prepared for stamping. To do this, take the following ingredients:
– zinc white powder – 35 g;
– acrylate powder – 80 g;
– dibutyl phthalate – 30 g;
– stearin – 30 g;
– monomer – 250 g.
Zinc white is poured into a container made of neutral material (glass or porcelain). They are thoroughly mixed with dibutyl phthalate, which serves as a plasticizer, and then with the monomer. After this, with constant stirring of the mass, melted stearin is introduced. After obtaining a homogeneous mass, part of it (50 g) is put into another bowl. Acrylate powder is added to it and also mixed with the mass.
Heat the mass placed in the mold using boiling water. For stamping, a special press with electrically heated mold can also be used.
The stamped figure (or usually several at once) is removed from the matrix. If it was not possible to remove the material from the mold, then you need to lightly tap it on the table. Excess stamping in the form of partitions is cut off and the sections are processed. They are usually always there, since the mass is put into the matrix with a small margin in order to avoid the formation of voids.
Using the same principle - heating the plexiglass and giving it the required shape with force - you can make curved parts of various shapes and sizes.
Method of bending organic glass using a soldering iron
In this way, small parts made of plexiglass are bent. To do this, use a heated electric soldering iron with a straight tip.
First, you should apply the tip to the prepared plexiglass strip at the location of the desired bend. Then the material is heated until a peculiar crackling sound appears - this is the limiting melting point, after which the sting is slowly moved a little further and removed.
Next, the plexiglass is quickly bent at the desired angle, for which manual effort is sufficient. Sometimes a pre-made metal mold is used into which the part is placed. You can also press a strip of plexiglass at the bend to a right angle template made, for example, from wooden block, and fix it in this position. After this, you need to wait for the material to cool completely, and only then separate the finished part.
Before bending the glass, you should pay attention Special attention to see if there is old tin solder on the soldering iron tip. If there are contaminants, they need to be removed, because the tin can stick to the plexiglass.
This technique has the only drawback, which is the limited size of the workpiece.
If you need to give large sheet plexiglass into a round shape or even roll it into a pipe, this can be done in the following way.
You need to find a suitable piece of metal pipe. Its diameter should correspond to the steepness of the desired bend of the plexiglass. Thus, the pipe will serve to heat and form a sheet of glass that will wrap around it. Therefore (if the quality of the bent product is important), a painted or heavily rusted pipe that contaminates the glass is not suitable.
Used as a heater blowtorch. The pipe will be heated by its flame from the inside. In this regard, it is important to choose a pipe of the required length. Too large will not heat up well enough and will not heat up the sheet of plexiglass placed on it. The pipe temperature required for further work should be 90–100 °C.
The pipe is secured by the edges to the stand. The design of this unique machine is complemented by clamps for holding glass.
A sheet of glass of the required size is prepared by first washing it with a soda solution. Then the workpiece is secured to the pipe with clamps and the pipe is heated, gradually bending the product.
If you need to completely roll the plexiglass into a pipe, you should calculate the length of the sheet in advance. To do this, you need to measure the circumference of the metal pipe using a centimeter and cut a glass piece of the same length.
Where and for what purposes it is not used - you can make hulls, front and decorative panels, used for “modding” computer cases, making three-dimensional figures, letters and much more. This material can also be used for dynamic light installations (flashing lights, running lights, etc.), the light in plexiglass spreads directly and evenly, resulting in very bright and beautiful things, which look impressive in the dark.
The main advantages of plexiglass are:
- high light transmittance - 92%, which does not change over time, maintaining its original color.
- Impact resistance is 5 times greater than that of glass.
- resistant to moisture.
- environmentally friendly, does not emit any toxic gases when burned.
- easy to process.
- the ability to create a variety of shapes using a hot air gun, without disturbing the optical properties, with excellent detail.
- mechanical processing is carried out with the same ease as wood processing
stability in the external environment.
- frost-resistant material.
- transmits 73% of ultraviolet rays, while UV rays do not cause yellowing and degradation of acrylic glass.
- stability in chemical environments.
- electrical insulating properties.
But there is perhaps the most important drawback - plexiglass scratches very easily, so you need to work with it carefully.
How to cut and process plexiglass?
Many people cut plexiglass using a jigsaw or a hacksaw, i.e. canvas. I don’t like any of these methods, primarily because a lot of debris appears during cutting, and the glass can be accidentally scratched, even though there is a protective film on it.
I want to offer you another, more advanced, simple and “functional” cutting method, after which not a single chip will remain - this is cutting using a hot spiral. This method Most suitable for thin types of plexiglass.
The advantages of this method:
- after cutting there is no debris left behind
- when cutting with a blade or jigsaw, plexiglass can be scratched or it can even crack, especially if the glass is thin.
- when cutting with a spiral, you can completely control the process and cut out any shape.
- after proper cutting, plexiglass usually does not even need processing, but if molten parts of the glass remain on the edges, they are cut off with a knife or processed with a file.
- in this way you can cut almost any plastic, not just plexiglass.
- no physical activity, sit in your chair and enjoy the cutting process =)
Now I’ll tell you how to make such a “cutter” and what you need for it.
First of all, we need a spiral, almost any will do, the main thing is that your power source can heat it. For example, you can get a spiral from old variable resistors, soldering irons, or buy a spiral for heating devices in the electrical goods department. The length of the spiral is selected experimentally, because They all have different resistance. For example, I used a spiral from a burnt soldering iron, with a diameter of about 0.3 mm, with a length of 7 cm and with a power supply of 12 volts, it becomes almost red hot (it consumes 1.5 amperes). By the way, we don’t necessarily need to heat the spiral until it’s red hot, otherwise when cutting the plexiglass will smoke and stink.
The spiral at both ends must be secured to metal pins, and the pins themselves must be soldered to the cable that will connect to the power source. If you want to get perfectly straight edges after the cut, then the pins need to be secured to something so that the spiral stays straight during cutting and is not bent like mine below in the photo. It is better to use a power source with an adjustable output voltage.
I made myself a design like the one below in the photo, I have already cut a lot of glass this way.
Cutting video:
How and with what to glue plexiglass?
Generally speaking, the technology for gluing plexiglass is not simple and is very different from gluing ordinary glass. If ordinary glass glued with silicone glue or a hot glue gun, then when gluing plexiglass this will not give the best results.
Plexiglas should not be glued, for example, with cyanoacrylate glue; the glass at the gluing points may turn white because of this, and it is impossible to clean it. This kind of glue is liquid and flows where it is not needed, and it grabs in a second, which is also not very good. The only advantage of cyanoacrylate glue is that it sets very strongly.
For gluing plexiglass I recommend using dichloroethane, this is a clear liquid, highly poisonous, so no need to snort it! Dichloroethane dissolves almost any plastic and glues them together. You can buy dichloroethane in radio parts departments, or where they sell adhesives.
Before gluing, the plexiglass joints must first be leveled and cleaned, then dichloroethane is evenly applied to the surfaces to be glued and they are connected without allowing them to dry. Then you need to prepare a mixture of plexiglass shavings and dichloroethane, take the shavings or pieces of plexiglass and dissolve them in this liquid. The consistency of the mixture should be similar to jelly; the seam should be filled with this mixture.
For the first time, it’s worth practicing on unnecessary pieces of plexiglass.
I repeat, dichloroethane is very poisonous, they shouldn't breathe! Work should be done in a well-ventilated area or outdoors. After work, you need to wash your hands well with warm water and soap.
Plexiglas bending
Plexiglas is plastic; it acquires plasticity at high temperatures; you can bend it at 90 degrees, or give the glass a certain shape. The most difficult thing when bending plexiglass is to bend it in the right place, as planned.
Plexiglas can be bent in boiling water using gas burner, in an oven or with a hot air gun. I'll tell you about bending plexiglass using a hot air gun and a spiral. To begin with, you need to draw, or better yet, scratch a line on the plexiglass; you should not use markers because... After warming up, marker marks will be difficult to remove. Next, we fix one half of the plexiglass on a flat table using a vice, take a construction hair dryer, or a hair dryer from a soldering station and begin to heat the glass along the line we have drawn. The temperature of the hair dryer should be set to around 150-180 degrees - depending on the type of plexiglass. As the heating progresses, as soon as the glass begins to yield, (by the way, this will be the optimal temperature), we begin to bend it; you should not remove the hairdryer during the process, you need to maintain the temperature and warm it up further. In general, I advise you to heat it better from both sides, with two hair dryers, if the plexiglass is thick, 5-6 mm. You need to bend in the direction away from the heat source.
In order to heat only the section of glass we need, I advise you to cover the rest of the section with something, just in case, leaving only a narrow strip open for heating and bending. Don't forget about the various cylindrical objects, metal pipes for example, which can be used as a template according to which you can make a bend of the desired radius, or even make a tube from plexiglass.
Using a hot air gun, you can make various forms from plexiglass for small structures, it is convenient to make the forms from wood, we grind, cut out the desired shape, put the plexiglass on it and heat it with a hairdryer, the glass will melt and begin to fit into the form. After bending, the glass must be cooled smoothly and evenly.
Just the other day, I came across another interesting way. Thin types of plexiglass can be bent using the same spiral; to do this, we stretch this spiral in the place we need, at a distance of several mm from the glass, and heat the wire. You will feel the moment when the glass begins to give in.
At home, cutting plexiglass is very rarely required. Usually this work is performed by specialists in workshops. However, this skill can also be useful in everyday life. After all, sometimes there is a desire to make a vase, an aquarium or a small decorative table with your own hands. So, the subject of our review is plexiglass. How to cut such material?
Features of the material
Not everyone knows what plexiglass is. How to cut it at home and what features does it have? First of all, plexiglass has performance characteristics durable plastic, and also looks like ordinary glass. This material is transparent. However, unlike glass, it does not break.
Thanks to these properties, plexiglass has become popular. How to cut it at home? In this case, not everything is so simple. The material itself is quite durable. Plexiglas is widely used. Indeed, in some cases, using ordinary glass is dangerous and problematic. Almost all materials can be processed available methods. However, there are some nuances that should be taken into account when working with plexiglass.
Laser cutting of plexiglass
How are plexiglass products made in production? Typically, a laser is used to cut this material. This is the most convenient method. However, it is simply impossible to use it at home. Thanks to the thin laser, a precise cut can be made. Even small parts future products. However, this cutting method has certain limitations: the laser beam creates high stress on the material. In the future, it is simply impossible to glue individual parts together.
It is possible to cut products from plexiglass only in industrial conditions. If necessary, you should contact the appropriate organization for assistance. The main thing is to make all the drawings in advance. It is also worth choosing an experienced master.
Plexiglas: how to cut?
In some cases, the use of a saw is allowed. It can be tape or disk. The latest type of saw is designed for straight cuts. In this case, the seam is neat and clear. As for it, it is suitable for making blanks. It is unlikely that it will be possible to cut clear edges with such a tool. To make the surface smoother, it is recommended to use a milling cutter.
It is worth noting that this method of cutting plexiglass can be used not only in production, but also at home.
Special equipment
Plexiglas products are cut with a high-speed tool. This allows you to get an even and high-quality seam. The speed of such equipment can be up to 4 thousand revolutions per minute. After this, the plexiglass undergoes additional mechanical processing.
However, one should not forget that this material has low thermal conductivity. Cutting at high speeds can cause the edges to heat up quickly. Some instruments have a Plexiglas mode.
A hacksaw will help out
If you need to cut plexiglass at home, you can use This is the most affordable tool. However, this method has a serious drawback: the cut area remains rough and rough. To eliminate such a defect, you need additional processing. Sandpaper or a file is usually used to smooth the cut area.
Cutting plexiglass with a cutter
Methods for cutting plexiglass at home can be completely different. Some people use a hacksaw, and others use a cutter. Essentially, this tool is a saw with just one tooth. To cut plexiglass, you will need a metal ruler of a certain length. This tool must be placed on the sheet of material in the place where it needs to be divided. After this, you need to run the cutter along the ruler.
When the cut reaches ½ of the thickness of the sheet, you can stop and then carefully break the material. If defects appear, they can be smoothed out. To do this, you need to sand the edge of the plexiglass with sandpaper. If desired, you can make your own cutter from emery cloth. Some experienced craftsmen For cutting plexiglass, pieces of glass are used. With this method it is required reliable protection for hands.
Using simple tools
If cutting plexiglass with a laser is an expensive pleasure for you, then you can cut the material using improvised materials. Very often, nichrome thread is used for such work. It needs to be heated before cutting. This will require a transformer with a power of 24 W.
As a result of simple manipulations, you can carefully cut plexiglass. When heated, it simply melts the material. This allows you not only to cut plexiglass, but also to cut out shaped parts.
Also, some craftsmen use this option for cutting plexiglass at home. The end of the screwdriver is usually pressed against the material. In this case, the tool must be held by the very edge of the handle. After this, the blade of the screwdriver is heated with a soldering iron, the power of which is 25 W.
The plexiglass should begin to melt. Using the tip of a screwdriver, simply draw a line in the place where the cut should be. After this, the plexiglass breaks easily. To get a straight line, you can use a metal ruler or a hacksaw blade without teeth.
In addition to the methods described above, you can cut plexiglass with a milling cutter or a circular saw. The thickness of the blade in this case should be no more than 1 mm. It is worth considering that smoke may appear during the cutting process. In this case, the edges of the material often foam due to the increase in temperature as a result of friction. This can be avoided. It is necessary to cool the working surface of the tool.
A band saw is more suitable for cutting workpieces before molding, since with such cutting there is no need to obtain a clear cut (for cutting cast acrylic, use band saw with a rotation speed of 700-800 m/min.). To obtain a clear and smooth surface when cutting out complex shapes, it is recommended to use a cutter. Circular saws allow you to make straight, precise cuts with a clear cut (when cutting cast acrylic, use circular saw with carbide-reinforced teeth with a rotation speed of 800-1200 m/min). When conducting minor works Saws with a blade for light metals can be used.
For more advanced cutting, it is preferable to use high-speed equipment. At high cutting speeds and minimum feed speeds, a high-quality edge can be obtained (when cutting extruded plexiglass using high-speed circular saws Recommended disk rotation speed is 4000 rpm. (For processing, it is necessary to use discs with a diameter of 250 mm, made of high-speed steel or reinforced with carbide. To avoid deformation, the saw teeth must be undone). cutting laser beam has a number of advantages: exceptional cutting accuracy, low waste, high quality cuts requiring little grinding.
However, this method contributes to the appearance of high internal stress in the material, and further gluing of such surfaces is not recommended. Cast plexiglass is easy to machine, but due to its 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 at high cutting speeds.
Attention! To avoid scratches during storage or machining, do not remove the protective film or paper covering.
Drilling plexiglass
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. It is necessary to ensure the smoothness of the edges drilled hole to avoid the formation of cracks. For deep drilling, it is recommended to lift the drill frequently to remove chips and limit heating of the material. When drilling cast plexiglass, use any metal screw drills. The drill diameter correction factor is +0.05 mm relative to the hole diameter. To avoid internal stresses when drilling, cooling is necessary cutting tool and material by cooling lubricants or compressed air.
Cold bending of plexiglass
Plexiglass, both cast and extruded, can be easily cold bent, but it should be observed minimum radius bending in order not to subject the slabs to excessive stress. The minimum bending radius should be 230 times the thickness of the plastic.
Plexiglas engraving
In most cases, it is produced using rippers mounted on pantographs and equipped with small diameter cutters (2-6 mm) various profiles. Laser cutting machines can also be used, which allow engraving by limiting the deep action of the laser beam.
Sanding plexiglass
Rough surfaces or surfaces with defects such as scratches are sanded with wet fine corundum sandpaper. 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 using a polishing machine.
Polishing plexiglass
Cut edges and matte surfaces can be highly polished mechanically using diamond cutters. However, if this is not possible, for example, the cut is curved, then flame polishing is recommended. This method involves treating products with a clean, “hard” high-temperature flame, but some precautions must be taken. For example, the surface to be sanded must be absolutely clean, and in addition, this method creates significant stresses, which must be removed by annealing before gluing or applying paint.
Welding and gluing of 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 overlapping or butt joints with a one-sided overlay, it is preferable to use SMM adhesive based on polymethyl methacrylate.
Before gluing, cast plexiglass parts must be annealed to relieve internal stress. The recommended annealing temperature is 65-80C depending on the softening temperature of the glass (90-120C), after which natural cooling is preferable.
Welding is also used to produce blanks for molding non-standard products, for fastening overlays and forming thickenings. Welding of cast plexiglass is carried out at higher temperatures (up to 300 0 C). After machining the seam, the finished part is subjected to heat treatment to relieve internal stress.
2. Sheets of extruded plexiglass can be glued to themselves and to other materials, resulting in a high-strength and durable seam. It is advisable to carry out heat treatment before gluing.
Materials for gluing extruded plexiglass:
Film type of adhesive: solution of polymethyl methacrylate in a volatile solvent;
Polymerizable type of glue: PMMA syrup with dimethylaniline (SMM), to which a polymerization initiator (benzoyl peroxide) is added at the time of gluing;
Other types of glue: epoxy, polyester, polyurethane and other brands AK-90, MP-88 (81), BF-2 (4.6);
Solvents: dichloroethane, methylene chloride.
After drying and hardening of the glue at room temperature, it is recommended to anneal for 2-5 hours at a temperature of 60C.
Welding is carried out using several methods:
Induction;
Radiation;
Ultrasonic soldering;
Vibrations;
Hot gas.
Hot molding of plexiglass
This type of processing allows you to give the material a variety of shapes. If the resulting part does not meet the desired shape, it can be reheated and then adjusted. Cast acrylic has a memory of shape and can easily return to its original position when reheated. With extrusion, this is only possible 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 plastic. Before molding, it is necessary to pre-heat dry the acrylic to avoid the formation of bubbles in the finished product.
The need for drying arises because a small amount of moisture may penetrate into the material during storage or transportation. Drying is carried out either in convection drying chamber with hot air circulation (at a temperature of 75-80 C for 1-2 hours per mm of thickness. As a rule, with a high moisture content, 24 hours of drying is sufficient), or using 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 of no more than - + 3 C. Cast glass is heated 3-4 min/mm of thickness to a temperature of 165-190 ° C.
Cast plexiglass quickly softens when heated, but its strength decreases slightly compared to extrusion glass. Cast and extruded acrylic react differently to heat. For cast sheets, uniform shrinkage of a maximum of 2% is possible, identical in all directions (the thickness of the sheet increases accordingly). For extrusion - from 3 to 6% in the extrusion direction and 1-2% in the transverse direction (for a 2mx3m sheet, the extrusion direction is the 3m side). Cast acrylic easily tolerates heating inhomogeneities of 10-15°C (overheated cast plexiglass, unlike extruded glass, does not crack or break when deformed); in the case of extruded glass, 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 you need to apply significant pressure, but extruded acrylic is molded easily and without special effort(recommended temperature range - 160-170°C; heating time - 3 minutes per 1 mm of material thickness). Molds (dies and punches) are made from various materials: wood, gypsum, aluminum, steel. Hot forming can be carried out in simple ways, for example, by placing the plastic after heating on a convex or concave shape, where it takes on its shape under its weight.
Molding can also be carried out by free drawing in a vacuum-tight chamber and free blowing with compressed air, both with the help of molds and without them. If it is necessary to bend a flat sheet in a straight line, then it is sufficient to locally heat the plastic along the bending axis using one or more straight heating elements, for example a nichrome string. Attention! When hot processing and/or molding, the protective coating must be removed and thoroughly cleaned, as any remaining adhesive or protective film When the sheet softens, it can damage its surface.
3. To avoid internal stress, cooling should be as long and uniform as possible. For best preservation printed form and to avoid deformation, the product must be left on the matrix until it is cooled to a temperature of 60-70°C. Molded products must be thermally conditioned to reduce stress before they are exposed to solvents, paints or self-adhesive films.