Many people wonder how to cut polystyrene foam at home. After all, this is one of the most popular and sought-after materials in construction, distinguished by many positive qualities and advantages. Polyfoam is intended for sound and heat insulation of residential premises. It is very easy to use, available in every hardware store, and its cost is very low. The only difficulty can be caused by the process of cutting foam boards without crumbling.
Ordinary foam plastic - advantages of the material
Polystyrene foam or expanded polystyrene is a material white, consisting of almost 95 percent air. It belongs to the category of environmentally friendly safe materials, therefore not hazardous to health. A huge variety of products are made from polystyrene foam, including food packaging.
The different sizes of the plates, as well as the structure in the form of small gas pores, determine the main positive properties of expanded polystyrene:
- High level of thermal insulation both from the inside and outside of the house. If you have learned how to cut polystyrene foam at home, you can install double insulation. Moreover, the cost of materials in any case will be much lower than that of other modern insulators that perform similar functions.
- Excellent acoustic insulation of rooms. This will be very useful in modern apartments, in which sound insulation is almost completely absent. Polystyrene foam is perfect for protecting yourself from noisy neighbors. And, naturally, the neighbors won’t hear either if you treat yourself to your favorite music at a high volume.
- Easy to install and install due to its low weight. The huge sheets weigh so little that even a child can handle them. The only thing worth paying attention to is the wind when doing outdoor finishing works. Even a slight blow of wind can disturb your workpieces, so it is not recommended to work with foam in windy weather.
- Environmental Safety. The material does not pose any danger to humans because it does not emit toxic gases or waste. The production of expanded polystyrene is carried out in accordance with all European norms and standards, so certain types of it may come into contact with food products.
- High resistance to the negative effects of fungi, bacteria, microorganisms, dampness, mold. Operation on outdoors for a long time will not cause any changes in consumer behavior, it will still be reliable and durable.
Before cutting foam, you should remember some rules for handling it. Thus, the vast majority of technical fluids cause irreparable damage to the material. IN Therefore, it is necessary to limit it from direct contact with solvents, gasoline, acetone and other similar liquids. Even pairs of the latter cause irreversible damage, which will certainly manifest themselves over time.
Another important factor is temperature. If polystyrene foam is used on surfaces with temperatures above 50 degrees Celsius, certain problems may arise. For example, the material begins to crumble and break even from simple touches. Therefore, its installation should be avoided, for example, next to stoves.
Areas of application – where foam is used
Due to the large number of advantages, this material has found the widest application, and not only in the construction industry. Thus, foam sheets can be used in such areas as:
- 1. Medicine - here polystyrene foam is indispensable as packaging for sharps and glass objects, as well as a case for equipment.
- 2. Organization active rest– if you cut the foam into sheets of the required sizes, it can be inserted into floats, life jackets and even buoys.
- 3. Design - specialists use the material to model and design various objects.
- 4. Shipbuilding - here foam sheets are used as an unsinkable filler for cargo compartments on boats, dinghies and other small vessels.
Thus, cutting foam plastic at home is relevant not only for performing construction work for soundproofing an apartment. So, having mastered this art sufficiently, you can make an unusual decorative figurine, build a model of a boat, and even independently reproduce the protection of the refrigeration circuit located in the air conditioner.
Processing foam without crumbling - simple and effective methods
The peculiarity of cutting polystyrene foam is that the material is very light and brittle; if handled incorrectly, it begins to crumble and break. Some rules should be followed when working with foam boards. You can use many different tools for cutting, including a soldering iron, a sharp knife, a grinder, and even nichrome wire.
Mechanical processing of expanded polystyrene, despite all its advantages, can cause some difficulties, especially for inexperienced beginners. If you don’t know how to cut polystyrene foam so that it doesn’t crumble, then first of all take care of purchasing a sharp knife with a rubber tip. When working, you should remember that the blade can very easily slide off the surface of the material, so you need to work very carefully and carefully, performing all movements exclusively “to the side” and “away from you.”
There are several basic tools for mechanical processing of polystyrene foam:
- In some cases, a simple shoe knife will do. But only in cases where it is necessary to cut foam plastic up to 40 mm thick. Having sharpened a knife sharply, you should not hide the sharpener far, since every one and a half to two meters you will need to sharpen the blade again. It is recommended to wear headphones or insert earplugs into your ears, since the cutting process is accompanied by a not very pleasant “squealing” of the foam.
- The next tool that works great with polystyrene foam is a wood saw. Using a hacksaw we cut slabs up to 80 mm thick. It is recommended to buy a tool with thin small teeth, in which case the cut will be smoother and more accurate. The main advantage of a hacksaw over a knife is the minimal risk of injuring yourself. And you will need to apply significantly less force during work.
- A jigsaw is also great for cutting foam at home. The process moves as quickly and simply as possible, all actions are performed very clearly and accurately, the likelihood of causing injury to yourself is reduced to almost a minimum. In addition, a jigsaw belongs to the category of common and popular tools; a real owner simply must have this tool at his disposal.
- A tool such as a grinder is also often used. If you need to cut foam plastic as quickly and without crumbling as possible, try to purchase the thinnest diamond discs. The cost of these discs is slightly higher than others, but the result is 100 percent worth the investment.
Unconventional cutting method - nichrome thread
All the methods presented above allow us to process polystyrene foam exclusively in a straight line straight line. In situations where you need to make an unusual shape, a semicircle or a zigzag, you can use unconventional methods. For example, nichrome thread. With its help, you will learn how to cut foam plastic so that it does not crumble, with minimal time and physical costs.
First you need to do some preparatory work for assembly necessary equipment. So, you should make sure you have a small spring, a 24-volt transformer and nichrome wire. The working surface of the table is set at an angle from 20 to 60 degrees. We stretch the wire across the table. We fix the ends of the wire on each side of the table with a spring.
After this, we attach the wires coming from the transformer to the wire. When current is supplied to the transformer, the nichrome thread heats up, which is evident from its appearance. All we have to do is lay down a sheet of any thickness in accordance with the pre-applied markings. Under its own weight and for a reason inclined surface the polystyrene foam will slide down and cut through at the same time.
No garbage, everything happens very quickly and without unnecessary movements. The only difficulty is assembling the necessary equipment, since not everyone has transformers.
Thus, there is nothing overly complicated about how and how to cut polystyrene foam at home. Even with an ordinary knife you can perform all the necessary operations. If you purchase better equipment, the processing process will take a minimum of time, without additional effort, noise and debris.
Cutting foam plastic - what could be easier? After all, ease of processing is one of the main advantages of this material. But in the end it all depends on your goals. What is important here is the amount of work, the thickness of the slabs used, and, of course, the complexity of the cut itself. I want to introduce you to all the tools used in this area, some of which are only suitable for industrial use, while others you can easily use at home.
A little about the material itself
Before moving directly to the most important thing, I want to devote a few words to foam plastic. Essentially, this material is foamed plastic, a set of thin-walled plastic vessels filled with air. The description is very exaggerated, but it very clearly conveys its device and the presence of technical characteristics associated with it.
What is the problem with cutting?
In the photo above, the tiny fragments that make up the foam board are clearly visible, and you can even see that in some places they have already flown off. This is where the difficulties associated with even cutting of this material lie: fragility. It crumbles easily or even breaks completely upon contact with various instruments or even just with your bare hands.
Thus, during the cutting process, it is necessary to achieve such a result that the tool passes through the foam with minimal resistance, without causing destruction of its structure.
Density is important
In addition to the technology you choose to implement your plans, important factor is also the density of the foam, easily determined by the markings applied to it:
- PSB-S-15. The cheapest and most fragile brand, which is used solely as thermal insulation material, fitting behind decorative finishing. Technical data:
- PSB-S-25. The most popular option when carrying out work, as it is still incredibly cheap, but at the same time has higher strength characteristics that simplify its operation. Technical data:
- PSB-S-35. These samples can withstand physical impacts much better, which is why they are widely used in the construction of swimming pools, sports grounds, lawns and foundation insulation. Accordingly, their cutting is easier with less waste. Technical data:
- PSB-S-50. This brand has the highest density, which allows you to create the most complex artistic figures from it with your own hands, even with simple tools.
Thus, the first thing to do to prevent foam from crumbling is to choose a product of the appropriate brand. Although, of course, if the quality of the cut does not matter in your situation, then there is no need to overpay for strength.
Tool No. 1: shoe cutting tool
A shoe knife is sharp enough that its blade can pass through plastic bubbles without catching them.
But there are still some notes on its operation:
- It is possible to cut only those sheets whose thickness does not exceed 40 mm;
- Blade gets dull pretty quickly, which requires sharpening after approximately every 200 cm of foam. But this only matters for large volumes of work;
- As the blade passes through the foam, it rubs against the plastic bubbles with a terrible sound. So be prepared.
If you have a lot of foam plastic slabs waiting for you that need to be cut with the tool described, I recommend putting on headphones right away, otherwise you will be in a very bad mood by the end of the work.
Tool No. 2: stationery knife
If you don’t have a shoe knife at hand, but you urgently need to divide the section into specified segments, then use a basic stationery tool designed for cutting paper sheets. All the problems listed above are also valid here, only instead of sharpening you should simply break off the blades, which in case of large volumes of work will lead to significant consumption.
If the cutting blade is heated, it will slightly melt the plastic foam capsules, which in turn will significantly facilitate the movement of the blade. By the way, the use of high-tech cutting methods for the material in question is based on this feature, but more on them below.
Tool No. 3: hacksaw
How to cut polystyrene foam at home if its thickness exceeds 40 mm? The simplest answer in this case is: hacksaw for wood. But I’ll immediately note that this tool is not universal, as it is only suitable for creating straight edges.
Try to look for a saw with the thinnest teeth, as they are less likely to catch plastic vessels when passing between them, which as a result has a beneficial effect on the quality of the cut.
Tool No. 4: “grinder”
The eternal companion of builders and mechanics, the “grinder”, is also used for cutting foam plastic. The main thing is to choose the thinnest metal circles to complete the task.
But, frankly speaking, I don’t really like this option, I’ll justify it:
- The squeal of the foam interacting with the wheel of the angle grinder is also accompanied by motor noise of the power tool itself. Here even headphones may not save your mood;
- Everything, literally everything will end up in foam chips, so cleaning will then be quite lengthy;
- Expense will be added electrical energy , which will then have to be paid.
A plus is that the grinder cuts the material for you. But this is true for metal, which is really difficult to cut with your own hands with just a hacksaw, while foam plastic practically does not resist under the influence of the listed tools.
Tool No. 5: laser machine
If you need not just to complete a ceiling or floor, but to create a complex advertising sign, scenery for a theatrical performance or architectural elements unusual shape, then it is best to turn to professionals who have special laser equipment, which, using their software, is capable of precise three-dimensional cutting of foam.
That is, in fact, the foam section can be given any shape at all. This already brings the process to the level of artistic art.
But there are also plenty of problems with this technology:
- The equipment itself is insanely expensive, and its operation is possible only by specially trained operators;
- Order required project will also be expensive for your family budget, so before making a final decision, take everything carefully.
Tool No. 6: nichrome wire machine
When you want to create, but it is impossible to have programmable laser equipment, you can build a special machine.
With its help, the foam will be cut with heated nichrome wire, which has the following advantages:
- Ability to create slices any artistic complexity;
- High speed and performance, which are equivalent to industrial;
- Lack of crumbs, since the edges are immediately sealed under the influence of high temperature.
You should work with such a tool in a well-ventilated room and with a respirator on, otherwise you may be poisoned by toxic fumes.
Manufacturing process
And how can you build such a miracle at home?
Instructions that I will gladly share will help you with this:
- To start we select necessary materials . I found the following accessories in my workshop, which were then successfully used:
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Polystyrene foam is used by builders for a variety of purposes. This material exhibits high thermal insulation qualities, so it is used to insulate building facades, floors and other objects. Various decorative elements are also made from this material.
Polystyrene foam is easy to process and easy to cut. But at the same time, the material can crumble greatly. The destruction of an array is a negative phenomenon. Therefore, it is necessary to properly handle this material, you need to know before starting work. At the same time, from solid foam plastic it will be possible to create not only slabs for insulation, but also decorative items. Their appearance will be neat, and the material will not be destroyed.
Features of foam
Foam plastic is in every way lightweight material. The polymer is mixed with air and foam filling components. Its structure is similar to glued balls. It is this feature that explains why we cut the foam instead of breaking it. Otherwise, the cutting will be uneven.
In some types of material, the balls of the structure are held tighter and do not crumble. But quite often the foam crumbles, sometimes very badly. Such destruction of the material is dangerous for the sheet. The fragility of foam plastic leads to a change in shape, a decrease in properties and functional qualities.
If it is necessary to adjust the dimensions of the array, this operation is carried out using special tool. In this case, the sheet will not be destroyed.
Types of tools
When studying the question of how to properly cut polystyrene foam at home, you need to pay attention to the types of tools. They are divided into mechanical and thermal. For independent cutting of an array, with small volumes of work, preference is given to the first group of means.
For home processing of foam plastic, novice craftsmen are recommended to choose a mechanical tool. Professional installers and designers prefer thermal cutting. In this case, it will be possible to create high precision edges and create objects of any complexity.
A thermal cutter is quite expensive. Novice craftsmen who carry out repairs at home rarely purchase such equipment. But for large volumes of work it is simply irreplaceable. Actions using a thermal cutter are performed quickly and efficiently.
Tool production method
When considering the question of how to properly cut polystyrene foam so that the sheet does not crumble, you should take a closer look at the method of making the tool. It can be factory-made or home-made.
Professional builders V mandatory purchase special certified equipment. Be it mechanical or thermal tool, for such purposes it is necessary to carry out work with factory-made equipment. The fact is that when creating such devices, the developers provided it with everything as much as possible. necessary qualities, safety and comfort. This is very important when doing a large amount of work.
But when doing repairs yourself, it is not profitable to purchase special equipment. In this case, you can create it yourself. This will be a more primitive device, but it will be able to cope with the tasks assigned to it.
Mechanical cutting
First of all, we should consider the main mechanical devices, which can be used to cut foam plastic. How to cut the material depends on the skills of the master and the amount of work. Such tools include a knife, grinder, saw and jigsaw. To independently cut the slabs in the process of arranging the insulation layer, it is better to use a knife. Its blade should be of medium hardness. This tool allows you to cut slabs up to 8 cm thick quite efficiently and quickly.
A jigsaw, grinder or saw is used only for special work. Professional builders use such equipment. In this case, the tool differs in a number of parameters from conventional angle grinders, jigsaws or saws.
If a thick blade and high rotation speeds are used, the foam can be easily damaged. Therefore, at home, a knife with replaceable blades is used for cutting.
Thermal cutter
Thermal equipment allows you to achieve high cutting accuracy. It is purchased professional craftsmen and designers. When carrying out a large amount of work at home, you should also pay attention to this type of equipment. In this case we cut the foam
The device is powered by the system or battery. Through the elements of this technique, electricity is supplied to the nichrome thread. The metal heats up quickly and strongly. This allows you to efficiently cut off excess foam and cut it in any direction.
The most accurate processing of the material is obtained by using a thermal cutter. It should be noted that foam does not react well to heat, but in this case the cut is made very quickly. Therefore its quality is high.
Homemade cutter
You can create a thermal cutter yourself. To do this you need to assemble a set necessary details. First of all, you will need a small transformer. You can take this part, for example, from an old TV.
In this case, you will also need to cut the foam with a nichrome string. It is pulled between two long screws. They need to be secured to wooden plank. Such material is known to not conduct current. Therefore, electricity from the transformer will only flow to the screws and string.
After connecting all elements, the voltage should be adjusted. It depends on the thickness. A string that is too hot will not allow you to cut the material properly.
Easy way to cut
The presented approaches make it easy to cut foam. Folk craftsmen give advice on how to cut such material. They came up with another way. It will be quite effective, especially when cutting large sheets polystyrene foam
To do this you will need a thin and strong string. Its ends are tied to wooden handles. If the sheet is large, you need to do the work together with an assistant. In this case, there are 2 people on both sides of the array. Everyone takes wooden handle with a string attached. Next, they move the thread along the pre-drawn markings. It heats up from friction.
The material is easily and quickly cut. If the leaf is small, you can perform this procedure yourself.
There are a few tips from professional installers to take into account when processing foam. It will be easy to choose what to cut it with. Experts say that each of the presented methods is suitable for cutting. It all depends on the skills of the master and the amount of work he performs.
Before cutting, the material must be marked with a simple pencil. With the mechanical and thermal method, the foam can heat up. In this case, he allocates environment harmful substances. Therefore, the work is carried out outdoors.
In this case, special equipment is used. Otherwise, when heated, the material will stick to the blade. A grinder or jigsaw works at low speeds. This allows heat to be removed from the cutting zone.
In construction, work is often carried out related to the insulation of structures, where polystyrene foam is used as the most inexpensive material. Accordingly, the density of such insulation is low, which, when cutting it, leads to the formation of a lot of debris, which is quite difficult to collect, since pieces of foam plastic tend to become electrified and stick to everything that comes their way. To facilitate the process of cutting insulating material, there are many methods and devices that help cut foam without crumbs.
Cut out foam parts with straight cuts
What and how to cut foam plastic
To cut a certain form for insulation, any device for cutting foam can be used:
- hacksaw for wood or metal;
- soldering iron;
- an angle grinder called a “grinder”;
- thin metal wire like a string;
- thermal cutter;
- foam cutting machine;
- jigsaw with heated file.
If you choose a hacksaw for wood, then its teeth should be as small as possible. All tools that are not heated to a certain temperature do not guarantee that the foam will not crumble. Such tools are used for small volumes of work, but when it is necessary to insulate all the enclosing structures of a house, it is better to use a foam cutting machine, the action of which is based on heating the cutting element.
How to properly cut polystyrene foam with a knife so that it does not crumble
When slabs are used in the process of insulating walls, ceilings, and roofs with your own hands polymer material, thermal cutters are not always justified. Designs, as a rule, have strictly geometric shapes, and it is quite possible to cut the material with a simple knife, the main thing is that the blade is thin and its length exceeds the thickness of the insulation sheet. Good tool for such work - a stationery knife if you have to cut thin polystyrene foam.
To cut foam with a knife, you need to choose a long blade The fact is that the blade of such a tool is very thin and when cutting a sheet of great thickness, a perfectly even cut is unlikely to be achieved; wrinkles may form on the cut, which will not allow making a tight connection individual parts insulation. And this will lead to the formation of cold bridges.
In addition to the knife you will need:
- A rigid measuring ruler or a ruler of ideal shape.
- Roulette.
- Simple pencil, marker.
They cut polystyrene on a solid base so that the sheet does not “play” in your hands. Marks of the required size are made on the surface of the polystyrene plate, after which a rigid ruler or strip is laid and sharp knife incision. If the length of the knife blade is not enough, you can make cuts on two opposite sides of the sheet, the main thing is not to lose the size. Then the sheet is simply broken along the cut. With proper skill, the work will proceed quickly, without unnecessary noise and waste of electricity. Of course, there will be debris, but not as much as from a hacksaw. The main thing is that the tool is very sharp and of the required length.
Before cutting the material, the tool must be heated and the blade must be sharpened periodically.
Foam plastic is cut with a stationery knife and a thermal knife - comparison of the cut line How to cut polystyrene foam without using heat tools
The principle of cutting sheets of foam plastic using a hacksaw, regardless of whether it is for metal or wood, is no different from cutting with a knife, the main thing is that the teeth are small and the blade is of sufficient length.
In this case, the cut will be smoother and a lot of small debris will not form. The saw movements must be made smoothly, without jerking. But even with this cutting method there will be a lot of expanded polystyrene crumbs.
You can cut foam sheets using an electric jigsaw or an angle grinder (grinder). However, with this method, a huge amount of garbage is guaranteed.
Grinder for cutting foam plastic The high speed of rotation of the grinder disk and fairly large teeth will provoke severe destruction structure of the material at the cutting site. When using a jigsaw, it is also impossible to obtain a perfectly flat surface on the cut due to vibration of the file, which also leads to the formation of small polymer debris.
The least amount of foam crumbs is formed when cutting it, if used homemade device for cutting foam plastic. The simplest form Such a device is an ordinary thin wire (string), with handles attached to the ends for greater convenience. The wire diameter should be chosen as small as possible, no more than 0.5 mm. One person cannot cope here; an assistant will be needed. The wire is installed along the intended mark on the foam and made uniform movements on both sides. As a result of the friction of the metal wire against the polystyrene foam, it heats up and the material begins to melt at the cut site.
Cutting foam plastic with a string – the method is the most effective in terms of the formation of a minimum amount of debris, but the time spent on such work is much longer than when cutting with other tools.
Thermal apparatus and devices
Cutting penoplex on a thermal machine The use of insulation does not always involve cutting it to the correct geometric dimensions. Sometimes you have to cut out semicircles, holes and other shapes with intricate contours. And here a knife or hacksaw will no longer help. But a machine for cutting foam plastic, which you can build yourself, can cope with such work.
Figured products made of foam plastic and penoplex The operating principle of such devices is that electrical voltage is applied to the cutting element, as a result of which it is heated to a certain temperature, which can be regulated by a special device. And given the fusibility of the material, cutting polystyrene foam with a heated string or wire is easy and quick. And at the same time, difficult-to-remove small debris is not formed.
How to build your own thermal cutter for foam plastic
If you choose the best way to cut insulation without creating small debris, then, of course, professional equipment will come first. But for home use purchasing such a device can be an expensive “pleasure,” which is why many craftsmen make a machine for cutting foam plastic with their own hands.
Schematic drawing of a thermal cutter for horizontal cutting of foam plastic Required materials and tools
To assemble a thermal cutting device you will need:
- Tungsten (nichrome) wire Ø 0.2 mm.
- Materials for making the frame are bars, metal profiles of any section. Springs for fastening tungsten filament.
- Rheostat or step-down transformer.
- Insulators.
- Terminals.
Tungsten wire can be purchased at a specialty store or obtained from household appliances- from any heater, including oil. Cut the desired piece of the spiral and straighten it so that it is even.
The heater's spiral is made of tungsten wire On hard and solid foundation you need to assemble the device frame. This could be a table, workbench, or some other surface. You will need to attach the vertical metal elements to the base at such a distance that a sheet of polystyrene foam can freely pass between them. Next to vertical posts springs are attached, insulators are attached to the springs, and tungsten wire is attached to them.
Springs are needed in order to maintain the wire in a horizontal position, since when heated, it tends to change its dimensions upward, which threatens it to sag if there are no springs. Instead of springs, you can use weights, the task of which will be the same as that of springs.
When you rarely use such a cutter, a battery can serve as a power source, which is undoubtedly safer compared to electrical network, where the voltage is more than 220 V, while the battery produces no more than 10 -12, and this is quite enough to heat the wire. If there is a rheostat, the voltage supplied to tungsten filament can be adjusted depending on the thickness of the sheet and the speed of its movement on the table.
This device will allow you to cut foam into horizontal plates, the thickness of which will depend on the distance between the wire and the table. If it is necessary to cut the material vertically, the wire must also be installed vertically.
1 - Tungsten wire 4 - Base of the device
The vertical foam cutter is suitable for cutting shaped elements from extruded and regular foam. When using similar device the cut is smooth and without crumbs. This device works on the principle of a jigsaw. In order to make a shaped part, it is better to use penoplex, a material obtained by extrusion from polymer feedstock - styrene, while polystyrene foam is not pressed styrene.
Cutting foam plastic with a modernized soldering iron You can quickly make a thermal cutter using a soldering iron. To do this, install a blade on the end of the tool if you need to cut foam plastic vertically or horizontally, or a crown from an electric drill when you need to make a hole or recess in the material. Instead of a crown, it is allowed to use a homemade round part, which is made of galvanized iron.
The main point of the article
How to cut foam plastic - mechanical tool– knife, file, electric – angular grinder, jigsaw, or using heated devices cutting element, everyone chooses at their own discretion. Thermal devices eliminate the formation of debris, but are expensive. For home use, there is an opportunity to save money and make your own thermal foam cutting machine.
How to cut polystyrene foam so as not to crumble
Polystyrene foam or expanded polystyrene refers to universal material, which is used for insulation and sound insulation in building structures. The basis of its structure is formed by foamed plastic. This explains why foam plastic quite often crumbles when cutting. 
When processing the material, you need to decide what to use to cut it so that the cut line is smooth and there are as few crumbs as possible.
Foam cutting is carried out using mechanical and thermal types of tools. Beginners, especially with small cutting volumes, are recommended to use a mechanical tool.
Mechanical cutting . The most common available tools include a knife, jigsaw, saw and grinder.
Ordinary knife . When choosing a knife, the main attention is paid to its blade. If it is sharp, then the cutting process proceeds faster and less waste is generated. The knife must be preheated before cutting.
The disadvantage of this method is that the use of a knife is possible with a foam thickness of 1-5 cm.
Shoe knife . As a rule, this knife is initially quite sharp. Therefore, its blade passes through the cellular structure of the foam with relative ease.
Disadvantages to use:
Ability to cut only thin sheets;
The knife blade quickly becomes dull;
The need to have a sharpening stone.
Stationery knife . The stationery version of the knife is best used for soft material. This knife has thin and flexible blades, so it is not used for processing thick slabs.
Advantages:
Little trash;
Availability of purchase;
Low cost.
The office knife has a set of replaceable blades. Dull blades break off, which leads to a lot of wastage.
Jigsaw
. Trimming with a jigsaw is used when cutting foam up to 10 cm in thickness. This method does not require much effort. 
Flaws:
The cut is never perfectly straight;
A sufficient amount of crumbs is formed;
Cannot be used when there is no power supply
Hand saw for wood . If the thickness of the foam reaches 40 mm, then it is better to cut it with a hacksaw. The method is quite simple and fast, without much physical effort.
A saw with fine teeth is better suited. This tool is only used to obtain straight cuts.
"Bulgarian" . The advantages of the grinder are that it seems to cut the foam itself if you use the thinnest circles.
However, it is not recommended to cut thick material with a grinder. You won't get a high-quality result, but there will be a lot of garbage.
In addition, this option is not very good due to the squealing noise that occurs when the foam interacts with the circle of the machine. Plus, the noise of the instrument’s engine is added to it. Therefore, if you are cutting a large number of foam boards, you should wear headphones from the very beginning of the work. Add to this list the electricity consumption that you will need to pay.
Nichrome wire cutter . Practice working with foam plastic shows that a high-quality cut is formed when using a tool with a heated wire. The edges are even, smooth, and there are practically no crumbs. The advantages of the method include high cutting speed and productivity in volumes similar to industrial ones.
The active use of the method is hampered by the difficulty of acquiring it due to its absence in stores. If there is an urgent need for a machine, there is only one way out - to make a cutter yourself. This is a separate question, to which many have been devoted good articles on the Internet containing step by step instructions and illustrations.
Easy way to cut
Cutting can be done with thin steel wire. It should be secured to wooden handles. They are placed at different ends of the surface intended for cutting. The cut is reminiscent of the process of sawing firewood. You will need an assistant to hold one of the handles. Friction causes the string to heat up, so the cut line is even and smooth.
Follow safety rules, taking into account that when heated, substances harmful to the body are formed and released. Work should be done in a well-ventilated area or outdoors.
Bottom line
From the review, we can draw a general conclusion that the process of cutting foam is quite simple and fast. The processing method is selected depending on the selected tool, the volume of work, and the shape (straightforward, tortuous or volumetric) in which the result should be obtained.
How and with what to cut polystyrene foam at home
The widespread availability of massive full-size foam boards automatically led to a boom in the use of a relatively durable, soft and at the same time easy-to-process material at home. Essentially, from a thick foam sheet it became possible production a huge number of all kinds of useful things, you just need to choose a way, how and with what to cut the foam in order to prevent deformation, breakage or crumbling of the material.
Why is it difficult to cut foam?
The widespread use of foam plastic material was largely limited by its porous structure, which resembles a compressed layer of tiny polystyrene cells filled with a gas-forming agent.
If you have ever cut foam sheets, you have probably noticed this feature:
- The denser and heavier the material, the easier it is to cut it with sharpened tools. The thinner the cutting edge, the easier and faster it is to cut even the hardest urea foam;
- Lightweight grades of foam are easiest to cut with power tools. The higher the cutting edge speed, the cleaner the cutting surface. IN industrial conditions thin foam plastic boards are cut with a thin water jet, with virtually no waste;
- When you try to cut a slab with a sharp blade in several movements, a situation arises where each new cut almost doubles the amount of foam sawdust and dust.
Advice! Craftsmen prefer to cut thin foam plastic slabs using the shoemaker's method. To do this, using a sharpened wide blade with great effort, a cut is made with the knife towards you, without changing the angle of inclination and depth of the cut.
Most modelers and craftsmen who work professionally with foam plastic will argue that cutting foam plastic boards is not at all difficult, especially since the density and strength of the material is relatively low. And they will be right. Cutting polystyrene foam at home is not difficult; you just need to accurately select the mode and equipment for cutting foam plastic.
Number of options practical application and the use of polystyrene foam for those who know how to work with their own hands has long exceeded one hundred. Dozens of foam materials are made from various models, injection molds, toys, stucco moldings, decorative elements, insulation, details speaker systems and even refrigerators. The main problem accompanying any attempts to process the material mechanically, is the selection of the mode, how and with what to cut the foam so that it does not crumble, as a result, cutting is always accompanied by the formation of a large amount of waste.
If the tip cutting tool is not sharpened enough or moves at low speed, when trying to cut the smallest gas-filled balls, the cutting edge does not cut them, but slides along the polystyrene foam, crushes them and tears them out of the compressed mass of foam. It is possible to cut a foam sheet in this way, but a huge amount of waste is generated.
Technology on how to properly cut a sheet of foam plastic
For home use, we can offer several proven methods:
- Using a sharpened shoemaker's or construction knife;
- A hacksaw for metal with an improved hacksaw blade;
- A powerful soldering iron with a razor blade attached to the tip;
- A thermal cutter or a hot nichrome spiral;
- A jigsaw or grinder.
Important! In any attempt to cut a foam sheet using hot blades, wires or a high-speed tool, it is necessary to work under a hood or outdoors, since when the foam melts, it releases a large number of volatile toxic substances.
If you need to cut foam plastic using a jigsaw or grinder, you should definitely use a respirator and safety glasses. When cutting, foam dust becomes highly electrified and sticks with incredible force to the skin of the hands, face, and gets into the eyes and lungs.
Scheme of cutting foam plastic mechanically
The easiest way is to cut a thin slab, up to 50 mm, using a regular knife, even a table knife. For this foam board Place it on the edge of the work table and make an incision. Cutting edge the knife should be as close as possible to the supporting plane. Before cutting, the blade must be sharpened and trimmed on a polishing wheel.
The part of the sheet to be cut must be supported so that the material does not break off under load. To cut with maximum quality, the knife is moved with little effort in one direction - “away from you”; the reverse movement of the blade is done “idle”. If you have to cut a sheet laid out on a table top with a shoe knife, then the direction of application of the force changes to the opposite - “toward yourself”.
It is strictly not recommended to cut thin-sheet foam material while hanging or in a vertical position.
It is much easier to cut foam with a hacksaw. For dense grades, the hacksaw blade does not need to be changed; for highly porous foam sheets side surfaces The blades are ground on a grindstone to remove tooth set. With a hacksaw you can cut in almost any position without restrictions.
The most productive tool for cutting sheets is an angle machine or grinder. Depending on the diameter of the cutting wheel, a grinder can cut foam up to 50 mm thick on the fly. In this case, the quality of the cut will be much higher than when using a knife or saw. The disadvantage of this method is the large amount of dust and chips. If you reduce the cutting speed of foam plastic to a minimum, the material will begin to burn and melt, which is not always allowed by the cutting conditions.
Simply cut the foam sheet using a jigsaw. In terms of productivity and cutting quality, a jigsaw is inferior to an angle grinder, but it has an invaluable advantage - it can be used to make shaped cuts that are difficult to obtain using other mechanical cutting methods.
Thermal methods for cutting foam plastic
The second most common method of cutting foam is a thermal cutter. Essentially, it is a nichrome thread laid on a frame in the form of a frame. When passing electric current along the nichrome wire, the metal surface heats up and melts the foam. There are several design options for the cutter. The simplest one looks like a nichrome string stretched on ceramic insulators installed at the ends of a wooden or metal frame.
With this tool you can cut not only foam sheets, but also wooden slats, plastic pipes, any material with a melting or decomposition temperature of up to 270 o C.
If you need to cut slabs with a long cutting length, then it will be more convenient to use a machine in the form of a vertical taut thread on a PCB stand.
For heating control nichrome string LATR or rheostat is used. Too much heat surfaces can lead to melting and even ignition of the foam. A remarkable property of this cutting method is the complete absence of dust and chips; in addition, the cut surface turns out to be melted, as if covered with alkyd varnish.
If in the process of processing foam you need to cut off only small fragments of the foam block, for example, when making a sculpture or model, it is best to use a nozzle for a powerful electric soldering iron.
Special mention should be made of the most interesting way cutting foam plastic with a laser. This may seem fantastic, even at home it is possible laser cutting foam plastic, photo. A conventional LED laser with a power of 2-5 W allows you to cut a sheet of foam along a completely arbitrary trajectory.
While such a tool is capable of cutting paper and foam plastic within 10-15 minutes, it will be very difficult to achieve large volumes of cutting with it.
Conclusion
You can cut polystyrene foam with a laser beam only if the white surface of the foam plastic is treated with a black or dark absorbing layer, for example, regular acrylic paint. It would be more rational to install a laser on the machine or homemade CNC carriage from a router. In this case, you can not only cut, but also form 3D models from thick foam blocks. To obtain exact dimensions models, the laser must operate in pulsed mode.
Discuss the article on the forum
How to remove mold in the bathroom
When making repairs, especially those related to redevelopment or insulation, a material such as polystyrene foam is often used. Its popularity is due to the fact that it is quite cheap and has good insulating properties. But many people have a question, like polystyrene foam, not only quickly, but also with high quality. So that the cut line is even and the edges are not “shaggy”.
Polystyrene foam, as you know, can be hard (hard) and soft. The hard one is well processed, and for this reason, by the way, it is popular among fishing enthusiasts - they make floats from it. But soft ones usually crumble. The thickness of the sheets (pieces) also varies, so there is no single recommendation for cutting foam plastic. But some advice can still be given.
If the foam is soft, then it can be cut into pieces with a paper knife. It cuts through foam like butter. However, you need to take into account that the blade of such a knife is quite flexible, so if the piece is “thick” enough, then it is unlikely to be able to maintain a straight line. And if it does work out, then the cut may not be vertical, but with a bevel.
Harder and thicker foam sheets can be cut:
- sharpened. If the thickness of the sample is not very large, then it is better to heat the knife and then cut it. Cutting will go much faster;
- hacksaw for metal;
- wood saw with fine teeth.
Those people who have tried cutting foam plastic with a jigsaw do not recommend using this tool. Can't make a straight cut.
Most best method– cutting foam plastic using nichrome wire. To do this, a rather primitive “machine” is assembled. The wire is stretched vertically, and current from a 12V transformer is passed through it. “Craftsmen” often adapt power transformers from old TVs for these purposes. A rheostat or variable resistance must be included in the electrical circuit. It will not be difficult to calculate it for a person familiar with the basics of electrical engineering.
Regulating the current strength is necessary so that the wire does not heat up too much. Excessive heating will cause the foam to melt, and sagging will form on its edges along the entire cut line, which cannot be removed “exactly”. This method is attractive because it allows you to cut out neat fragments not only along a straight line, but also along curves and kinks. Essentially, this makes cutting universal.
You can try it with a grinder. However, you should choose the thinnest disk. But when using such a tool High Quality it will not be possible to get a cut, this will give the same result as when using a jigsaw. Some people advise using a soldering iron with a specially prepared thin tip.
All of the above methods are good in their own way. Therefore, you need to choose according to the circumstances, taking into account all the features of such cutting.