Cutting foam plastic doesn’t seem to be a difficult task, but to do it accurately, you need to have skill and know some secrets. How and with what to cut polystyrene foam at home and how to make a machine yourself to simplify this work? I'll tell you now!
Foam cutting
The scope of application of polystyrene foam is very wide. This material is used to make parts for aircraft modeling, it is used in the manufacture of toys and furniture, three-dimensional letters or sculptural elements for advertising are cut out of it, etc. We are interested in a very specific area - construction.
Types of cutting
In construction, foam plastic is used as insulation for roofs, walls, floors, ceilings, foundations and other structures. In the vast majority of cases, thermal insulation consists of sheets of foamed polystyrene, which are sold in stores and have standard sizes.
During installation of sheets, they constantly need to be trimmed, and here the following cutting options are possible:
- Longitudinal. This refers to the case when you need to cut a sheet of foam along its plane, for example, into two parts. For example, to make two sheets 25 mm thick from one sheet 50 mm thick: neither a knife nor a hacksaw will help here;
- Transverse. When you need to cut a piece of the desired shape from a sheet, that is, you will cut perpendicular to the plane of the sheet itself. In this case, you can use a knife, saw and other similar tools;
- Through. Often it is necessary to make holes in the thermal insulation layer for entry electric cable, pipes or other communications. If you have some skill, you can get by with a knife, but there are more effective tools, which I will tell you about;
- Curly. It is used when the edge of the sheet needs to be cut according to a clearly defined pattern with curved lines and complex profile. An ordinary knife will not work here, and a special tool will be required.
Cutting tool
Cutting foam can be done with a variety of tools. The most popular:
- Construction knife. During insulation work, a knife is most often used to trim sheets. It can be a construction, stationery or shoe knife. The main thing is that it is well sharpened. The knife is carefully drawn along the cut line; strong pressure is not necessary. If the sheet is not cut through, it is broken along the slot;
- Hacksaw. To cut thick sheets, it is convenient to use a hacksaw for metal or wood with small tooth. Special saws for foam plastic are sold;
- Nichrome wire. A piece of thin nichrome wire is heated by passing electric current. A hot string, fixed in a certain way and stretched, cuts foam like butter;
- Thermal knife. In essence, this is a soldering iron, the tip of which is made in the shape of a knife blade. The blade heats up and perfectly cuts any plastic, including foam;
- Laser ray. You can cut polystyrene foam using a laser. This technology is used when making sculptural elements or in large industries to cut out a wide variety of shapes.
In construction, cutting of even, rectilinear shapes is most often required, which a knife can handle quite well. In this case, a thermal knife is an ideal option.
If you need longitudinal cutting to thickness, a nichrome string is best.
How to make a cutter from nichrome wire
How to cut foam thickness? This question often arises before a builder when it is necessary to unravel a sheet of insulation and make it thinner. A nichrome wire cutter is suitable for these purposes.
The idea of the machine is quite simple: a string is pulled over a tabletop made of board or plywood, through which a current is passed. The string is set horizontally at the required height, heats up from the current and cuts the sheet, which the cutter moves along the tabletop.
Making such a machine with your own hands is quite simple:
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Making a table top. Choosing a board for the tabletop. It can be thick plywood or MDF, solid board, for example, a door from a cabinet or a tabletop from a table. |
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We fasten the studs. We attach threaded steel studs to the corners of our tabletop. To do this, we drill holes and insert anchors into them, which we secure with nuts. |
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Heels on the reverse side. On the back side of the tabletop we stuff heels from boards. They are needed so that the ends of the studs do not rest on the floor, and the structure stands level. In addition, it will be possible to run wires under the tabletop. |
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First wire. We connect the first wire to the stud. It is better to wrap it around the anchor under the washer, solder it and tighten it with a nut. |
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Second wire. Similarly, connect and tighten the second wire with a nut. |
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Holes in washers. We take two washers that fit loosely onto the studs. Drill holes as shown in the photo. |
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Sharpening washers. Opposite the holes, along the inner edge of the hole in the washer, we sharpen. This is necessary so that the washer fits exactly into the grooves of the thread and cannot move along the stud. |
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Spring. We put the washers on the studs and put the holes inward. We thread the end of the spring into one of them. Any steel spring that works in tension, for example, from a folding bed, will do. |
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Attaching the wire to the spring. We tie a nichrome wire to the free end of the spring and measure the distance to the opposite pin. Leave a margin of 30-40 cm and cut off the excess. |
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String tension. Insert a screwdriver into the end of the spring and stretch it. With the other hand we pass the wire through the hole in the washer and tie it tightly. |
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Selecting a power source. It is best to use a step-down transformer, which gives an output of 6-12 V at a current of 6-10 A. A charger for car batteries, a power supply for a computer, or a transformer from an old TV are suitable. |
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We adjust the tensioned thread in height. To do this, you can use a square, ruler or tape measure. |
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We connect the machine to the network. We connect the supply wires coming from the studs to the transformer outputs. Apply voltage to our cutter and wait 10 seconds for the thread to warm up. |
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cutting. We take a sheet of polystyrene foam and run it along the tabletop. The wire will cut pieces of the thickness we need from the sheet, which we set earlier. When cutting polystyrene foam with a hot wire, toxic smoke is released. It is necessary to use a respirator and work in a well-ventilated area. |
Conclusion
I think now you understand how and with what foam is cut. Eat different ways and tools, choose the appropriate one for a particular case. To better understand the topic, watch the video in this article and ask questions in the comments if you have any.
Heat and sound insulation building materials on the market are presented in wide range, is polyethylene foam, mineral and basalt wool and many others. But the most common for insulation and sound insulation is extruded polystyrene foam and polystyrene foam, due to its high physical and chemical properties, ease of installation, low weight and low cost. Polystyrene foam has a low thermal conductivity coefficient, high coefficient sound absorption, resistant to water, weak acids, alkalis. The foam is resistant to ambient temperatures, from the lowest possible to 90˚C. Even after decades, polystyrene foam does not change its physical and chemical properties. Polyfoam also has sufficient mechanical strength.
Foam plastic still has very important properties, this is fire resistance (when exposed to fire, foam does not smolder like wood), ecological cleanliness(since polystyrene foam is made of styrene, you can even store it in containers food products). Fungi and pockets of bacteria do not appear on the foam. An almost ideal material for insulation and sound insulation during the construction and renovation of houses, apartments, garages, and even packaging for food storage.
In shops building materials foam is sold in sheet form different thicknesses and sizes. When repairing, foam sheets of different thicknesses are often needed. If you have an electric foam cutter, you can always cut sheets from a thick plate required thickness. The machine also allows shaped foam packaging from household appliances into slabs like the photo above and successfully cut thick sheets of foam for furniture repair.
How easy it is to cut foam into homemade machine, the video clip clearly demonstrates.
If you want to make a cutter for foam plastic and foam rubber, many are stopped by the difficulty of organizing the supply of supply voltage to heat the nichrome string to desired temperature. This obstacle can be overcome if you understand the physics of the issue.
Machine design
The basis of the device for cutting foam plastic was chipboard sheet(chipboard). The size of the slab should be taken based on the width of the foam plates that are planned to be cut. I used a furniture door measuring 40x60 cm. With this size of the base, it will be possible to cut foam plates up to 50 cm wide. The base can be made from a sheet of plywood, wide board, secure the cutting line directly to the work table or workbench.
Pulling a nichrome string between two nails is the limit of laziness home handyman so I implemented the simplest design, providing reliable fixation and smooth adjustment of the height of the string during cutting above the surface of the machine base.
The ends of the nichrome wire are attached to springs mounted on M4 screws. The screws themselves are screwed into metal posts pressed into the base of the machine. With a base thickness of 18 mm, I selected a metal stand 28 mm long, so that when fully screwed in, the screw would not extend beyond the bottom side of the base, and when fully unscrewed, it would provide a foam cutting thickness of 50 mm. If you need to cut sheets of foam or foam rubber of greater thickness, then it will be enough to replace the screws with longer ones.
To press the stand into the base, first a hole is drilled in it, with a diameter 0.5 mm smaller than the outer diameter of the stand. In order for the posts to be easily hammered into the base, the sharp edges from the ends were removed using an emery column.
Before screwing the screw into the rack, a groove was machined at its head so that the nichrome wire could not move arbitrarily during adjustment, but would occupy the required position.
To make a groove in a screw, you must first protect its threads from deformation by putting on a plastic tube or wrapping it thick paper. Then hold it in the drill chuck, turn on the drill and attach a narrow file. In a minute the groove will be ready.
To prevent nichrome wire from sagging due to elongation when heated, it is secured to the screws through springs.
A spring from a computer monitor, used to tension the grounding conductors on the kinescope, turned out to be suitable. The spring was longer than required, so we had to make two of it, for each side of the wire fastening.
After preparing all the fasteners, you can fasten the nichrome wire. Since the current consumed during operation is significant, about 10 A, for reliable contact of the current-carrying wire with the nichrome wire, I used the fastening method by twisting and crimping. Thickness copper wire at a current of 10 A, it is necessary to take a cross-section of at least 1.45 mm 2. You can select the wire cross-section for connecting nichrome wire from the table. I had at my disposal a wire with a cross-section of about 1 mm 2. Therefore, each of the wires had to be made of two with a cross-section of 1 mm 2, connected in parallel.
If not known electrical parameters nichrome wire, then you must first try to connect a low-power electrical appliance, for example a 200 W light bulb (current will flow about 1 A), then a 1 kW (4.5 A) heater, and so increase the power of the connected devices until the nichrome wire of the cutter heats up to required temperature. Electrical appliances can also be connected in parallel.
The disadvantages of the latest connection scheme for a nichrome spiral include the need to determine the phase for correct connection and low efficiency (coefficient useful action), kilowatts of electricity will be wasted.
Polystyrene foam is used in many construction work. It has good thermal insulation. However, this is a rather fragile and crumbling material. Therefore, when cutting it, special equipment is used. Otherwise, the edges will be uneven, and the material itself will lose its thermal insulation qualities at the joints.
Special equipment is on sale. However foam cutter you can do it yourself. This will save a lot of money family budget. How to create different variants tool for cutting foam plastic, it will be interesting for every master to know.
Tool type
Creating manual foam cutter, should be studied existing varieties this tool. There are mechanical and electric varieties. If the foam product is small in size and cutting accuracy is not so important, you can give preference to the first option of the tool.
However, in order to ensure a tight fit of the foam plates to each other, it is necessary to ensure high accuracy cutting The edges should be smooth. In this case, it is possible to create an insulating layer High Quality. Its heat loss will be minimal. When uneven cutting occurs between joints, large gaps. Through them, heat from the room will escape to the outside.
Professional designers and builders use exclusively electrical equipment for cutting foam. It is quite possible to create such a tool at home.
Simple electric cutter
Considering how to make a foam cutter, you should study the design of the simplest equipment of this class, which runs on electricity. In this case, you will need to prepare a thin guitar string and several batteries (for example, from a flashlight).
The operating principle of this equipment is simple. The battery structure forms a single unit. A guitar string is connected to it. When electric current passes through the circuit, it will heat up. It is in this state that the string can easily cut a sheet of foam.
When using such a tool, the material will melt. The string heats up to 120 ºС and even more. In this case, it is quite possible to cut several large slabs made of polystyrene foam. If you need to do a large amount of work, this option will not work. The batteries will run out quickly. We will have to provide an option for connecting the system to a household network.
Types of electric cutters
Electric foam cutter can be used for various purposes. This will determine the type of design and overall performance characteristics of the equipment. There are three main types of homemade cutters.
The first category is used for linear cutting. The second group includes cutters used to perform figure cutting material. Designers use them. This type is used less frequently for home repairs. There is also a tool with a metal working plate.
Such equipment must have a step-down transformer in its circuit. It must be rated for a minimum power of 100 watts. The secondary winding of the transformer must have a cross-section of at least 1.5 mm. It must withstand a voltage of 15 V. In this case, you can achieve high performance results.
Features of work
Studying how to make your own handheld foam cutter, it is also necessary to consider the operating features of such equipment. As mentioned above, such an instrument has a string. It heats up and melts the surface of the foam.
This material reacts quite poorly to heat. Therefore, it is important to maintain the technology of the entire process. Cutting using a hot thread is done quickly. This allows you to achieve high quality cuts.
It's easy to check the string's heating level. To do this, a test is carried out on a test piece of polystyrene foam. If, when immersing the thread, long pieces of material remain on it, it has not yet warmed up enough. If there is no foam on the string at all, then the temperature is too high. In this case, you will have to cool the instrument a little. With proper heating, it is possible to perform fast, accurate cutting.
Line cutting cutter
Linear DIY foam cutter will allow you to create blocks from the material of the required dimensions. This significantly speeds up the work of the master. If necessary, this tool can be used to cut circles, triangles or squares into the foam.
Two racks are installed vertically on the table surface. Two insulators are attached to them. A nichrome thread is stretched between them. This alloy heats up quickly, providing sufficient temperature for cutting. A freely hanging load is passed through one of the racks. Contacts from the transformer are connected to the thread.
The current passing through will heat it up. It will be taut all the time thanks to the weight hanging from one side. This is necessary, since the string may sag when heated. If desired, the design can be modified by adding a spring instead of a load. However, the original version is easier to implement.
Line cutting process
Considering how to make a foam cutter with your own hands, you also need to understand how to work with them correctly. Cutting can be done vertically or horizontally. To do this, the thread is pulled in the appropriate position.
If the string is stretched horizontally, you can use it to make the same cuts. The foam is pulled evenly across the table. The thread will cut it evenly into the required pieces.
When cutting a structure vertically, a frame made of metal or plywood is added. A holder is installed on it. An insulator and a nichrome string are connected to it. On its other side a load is suspended. It will go through a hole drilled in the table. It must be large enough and covered with a special insulating material. Next, you can perform vertical cutting.
Shaped cutting
If you need to cut fairly large sheets of foam or create decorative elements, sculptures made from this material, a special type of equipment is used. You can also make it yourself. It's manual foam cutter. It is made on the basis hand jigsaw or hacksaws. In them, the cutting element is replaced with a nichrome string.
If you need to create curly elements, you can make several tools various shapes. A wire is connected to the handle of the jigsaw. It must be carefully isolated. Otherwise, it will be unsafe to work with this equipment. A nichrome string is attached to the wire contacts. This can be done using nuts and screws with washers.
Also, a pulse soldering iron or wood burner may be suitable for creating such equipment. This tool is considered convenient. Their working element is removed from such equipment and replaced with a piece. In this case, the threads can be given different shapes.
Cutter with metal plate
Exists foam cutter, in the design of which it is used To create this equipment, you can remake a soldering iron. Equipment with a power of 60 W is suitable. Removed from the device a heating element. Instead, a plate is installed here.
One side of the copper blank needs to be sharpened. This will allow you to create a more accurate cut. The sharpening angle should not be made too large. The cutting will be done using heat. To find the required level, you will have to experiment on a test piece of foam.
This method is also used by craftsmen of various skill levels and profiles. If necessary, the copper plate can be replaced with a steel billet. This option will require more effort when sharpening. But with the help of such a tool you can cut denser polymer materials.
Choosing which one foam cutter is more suitable for the work of a master, you should take into account the recommendations of professional builders. The greater the volume of work performed, the more complex the design will be. A simple battery-powered cutter is quite suitable for cutting several blocks. However, to perform a large amount of work, preference should be given to network types of equipment.
When cutting, the foam heats up. At this moment, they stand out from it into environment substances unsafe for human health. Therefore, work is performed in a well-ventilated room or outside.
In order not to make a mistake with the cutting configuration, you should mark all the lines with a pencil before starting the action. This will avoid mistakes when cutting. These simple recommendations will allow you to do the job quickly, correctly and safely.
Having considered what options for foam cutters you can make with your own hands, every master will be able to choose the best option for myself.
The issue of home insulation is very relevant these days. Cladding house facades with foam plastic is one of the most popular types of insulation. And this is very justified, because... the process of such insulation is simple and clear, and all necessary materials always available for free sale.
But everyone knows that gluing foam plastic is very convenient on flat wall. With any method of gluing foam plastic to the wall: using dry-mix glue, foam or glue-foam, it is always very important that the foam sheet fits tightly to the wall and does not create air gaps.
If the wall is smooth, then no questions arise. But, unfortunately, the walls of old houses are not ideally even. Yes and different design features structures sometimes create differences in the plane of the wall.
This drawback can be partially mitigated by laying the foam on a thicker layer of glue. But the maximum permissible thickness of the adhesive layer often cannot cover the magnitude of the differences in the plane of the walls. In addition, too large differences lead to unjustified overuse of glue.
The only way out of the situation remains is to trim the foam according to its thickness. But doing this with a hacksaw is very inconvenient and takes a long time, especially if you need to cut a large number of polystyrene foam. In addition, during cutting, a large amount of debris is generated in the form of foam balls. And the surface turns out to be uneven and the accuracy of such cutting is very conditional.
In order to quickly and evenly cut foam to the desired thickness, you can use a foam cutting machine. This device can be made independently, absolutely with your own hands.
Operating principle and design of the foam cutting machine
The operating principle of the machine is based on the fact that foam plastic easily melts under the influence of temperature. Thus, if you run a thin heated wire over it, it is easily cut, forming a perfectly flat, smooth surface.
To manufacture the machine, the following components are needed:
- LATR (laboratory autotransformer) or car battery;
- nichrome thread;
- stands for fastening nichrome thread;
- spring (1-2 pcs.);
- board-tabletop;
- copper wire.
A nichrome thread (spiral) is used as a cutting object. You can either buy it in a store or extract it from old household appliances, in which they were used as filaments (hair dryer, for example). The thickness of the spiral can be 0.5-1 mm. The most optimal thickness is 0.7 mm. The length depends on the width of the foam that will be cut.
An important element of the device for cutting foam is LATR. But if it doesn’t exist, then it can be made using an old transformer and a device for charging car batteries.
You can also use a computer power supply, in which wires providing 12 W (yellow and black) are used to connect to the spiral.
To operate such a machine, it is enough to have an output voltage of 6-12 W.
It is necessary to correctly adjust the length and thickness of the filament so that it matches the voltage. If the thread gets too hot, it may burst. Well, if the thread heats up slightly, then cutting will occur slowly.
Can also be used as a power source car battery. It can be used in conditions where there is no electricity on the site.
For different tasks you can do different designs devices for cutting foam.
Basically, these devices will differ in the length of the spiral. To cut polystyrene foam into bars, you need a short spiral length.
You can install two spirals and cut the sheet into several bars in one pass.
Two spirals cut the sheet into three parts in one pass. The stand has guides for smooth feeding of foam.
But, as a last resort, foam plastic can be cut into bars with a hacksaw. It is much more difficult to cut foam plastic to thickness, and even to a given size. Therefore, let’s look at how to make a machine for cutting foam plastic to width.
Step-by-step instructions for making your own machine and cutting foam plastic
Step 1. Preparing the tabletop. You can take any piece of chipboard as a tabletop for a machine for cutting foam plastic with your own hands. the right size. The surface on which the foam will move must be smooth. Holes for the racks are drilled in the tabletop. It is convenient to use metal pins with threads with a diameter of 10-12 mm as racks. The height of the racks should correspond to the thickness of the foam sheets plus a headroom. The pin is fixed with nuts.
To give the structure stability, bars are attached to the bottom of the tabletop, which will also serve for the safe passage of the electrical wire.
Step 2. Connecting the current supply wires. From below, under the tabletop, the wires are connected to metal stand rods: the wire is wound around the lower end of the pin and pressed with a bolt.
The second end of the wires must be connected to a power source, depending on the selected method. The most best connection there will be a connection through a plug that will connect to the LATER socket. Connection is possible through self-clamping terminals, as well as by twisting and soldering. This depends on the selected power source.
In any case, the connection must be made in accordance with the rules for working with electrical installations and devices, be convenient for work and safe during operation.
Step 3. Fastening the nichrome spiral. A nichrome spiral is fixed between two posts. A spring is attached to one end of the spiral (there may be two of them).
The spring is needed to tension the nichrome thread during operation. The fact is that when heated, the nichrome thread lengthens and sags. A thread in this condition will not produce a quality cut. Therefore, the thread is fixed in an initially tense state, so that the spring is slightly stretched.
To attach the nichrome thread to the pin, washers with an internal diameter slightly larger than the diameter of the pin are used. A small hole is made in the washer for attaching the spiral itself. A small sharpening is also done on the side internal diameter so that the washer can be fixed on the thread of the pin.
A spring with a spiral attached to it is inserted into one washer and put on the first pin. The second washer is put on the second pin and drilled hole thread a nichrome spiral. Next, it is tightened so that the spring stretches and fixed.
Step 4: Cutting the foam. To spread a sheet of foam into two sheets of a given size, the spiral is set to the desired height. The required distance is measured with a ruler.
The machine is then connected to a power source. The thread heats up and now you can cut the foam, smoothly moving it forward along the countertop.
The cutting speed depends on the filament temperature, which in turn depends on the applied voltage and the thickness of the filament itself. You should not try to apply more voltage to achieve high speed, because... this can lead to rapid filament burnout. Here, a balance between tension, thickness and length of the thread must be selected experimentally. The thread should not overheat during operation. When heated, it turns red or scarlet. But it should not turn white - this indicates that the thread is overheating and that it is advisable to reduce the voltage, otherwise the thread will not last long in this mode. Of course, smooth adjustment is easy to do if LATER is available. But if it is not there, then laboratory block The power supply can also be made from a computer power supply; the video below has more information. After you have made this foam cutting machine with your own hands, you need to make sure that the device is safe.
It must be remembered that all activities must comply with safety regulations for working with electrical appliances. The power source must be grounded and all connections must be carefully insulated. All work on assembling the machine must be carried out with de-energized wires. The machine is connected to the electrical network only while working with polystyrene foam. After work it must be turned off immediately. When operating the machine, avoid touching metal parts and the nichrome thread itself.
Step 4: Cutting the foam at an angle. Sometimes it becomes necessary to cut the foam so that one side is higher and the other is lower.
To do this, the spiral is set at an angle with the required parameters. In this way, foam sheets of various sections can be obtained.
Useful video
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The process of production and installation of foam plastic is not complete without its trimming. Without giving the blocks the required shape, the process of transportation and sale becomes more complicated. In each individual case, panels of a certain size are required for installation on a building or any device. What can be used for high-quality cutting of polystyrene foam? This will be discussed in the article.
Why difficulties arise
Polystyrene foam is a material that consists of granules compressed under certain conditions. Although the granules are sintered together, they do not fuse, which makes the granules easy to separate. This structure creates difficulties in the process of cutting the material. If anyone has had to deal with cutting foam plastic, it is easy to notice that sheets of high density are cut easier and for this you can use a well-sharpened tool with a thin tip. You can cut using power tools. Moreover, the higher the speed of the blade and the smaller the tooth, the faster and easier the cut.
In industrial conditions, foam cutting is carried out by other methods, one of which is hydroforming. A thin stream of water is applied to the block under high pressure, making it easy to cut and leaving virtually no waste. Another method is to use nichrome thread. It has a high resistance, so when electricity is passed through it, the temperature rises to a certain value, which causes the foam to melt. Industrial machines have several threads installed at once, which perform cuts in several planes.
Cutting technology
Cutting technology and all the tools that are used for these purposes can be divided into two large groups:
- mechanical tool;
- electric.
Each method is worth considering separately.
Mechanical method
The mechanical method of cutting foam plastic involves the use of the following tools:
- knife;
- jigsaw;
- saws.
The first cutting method involves the presence sharp knife. Most often, a shoemaker's knife made of rapid is used for these purposes. Its advantage is a durable handle and a special sharpening angle. But this option is suitable only for those cases when it is necessary to perform work on cutting foam plastic with a thickness of up to 4 cm. If we're talking about For sheets with greater thickness, a blade of greater thickness will then be required, since one that is too thin can bend, which will lead to the cutting line. In addition, during the cutting process you will need to periodically adjust the blade, so you need to keep a stone of the required grain size on hand. After marking the foam sheet, you need to move the knife along the cutting line towards you, holding it at an angle. In some cases, you will need to make several passes to achieve the desired result. The blade needs to be adjusted every two meters of the cut.
Another tool that is great for cutting foam but produces a lot of waste is a hacksaw. In this case, it is necessary to choose a product with a fine tooth. A metal blade will not cope with the task effectively, so a hacksaw is used. Thanks to the longer length of the hacksaw blade, you can cut sheets with greater thickness. Wherein the best solution there will be a hardened tooth without a large set, which will make the cutting line thinner. The advantage of using such a tool when cutting foam is greater safety, since the sharp part of the blade is not directed towards the body.
The power tool is also suitable for cutting foam. Excellent tools in this regard are a reciprocating saw and a jigsaw. The difference between them is the speed and depth of cut. The effect is in many ways comparable to that achieved when working with a hacksaw. For work, it is better to purchase attachments with a minimum tooth blade for wood. Using a jigsaw gives you greater freedom when it comes to making shaped cuts. This is easy to do because the width of the canvas is small. The cut is more accurate by adjusting the speed of the blade. It is recommended to turn off the pendulum stroke that is applied to the wood during the process to reduce waste.
Note! If you don’t have any other tool at hand, you can use a grinder with a diamond blade to cut foam. In this case, the rotation speed must be selected in such a way that it does not melt.
Nichrome thread
The most comfortable way to cut foam is with a hot nichrome thread. At correct selection speed, it is possible to achieve a minimum seam and not melt the ends. The essence of cutting is that the sheet is passed through a wire along a marked line. You can make such a cutting device yourself. To do this you will need:
- LATR or transformer;
- nichrome thread;
- insulators;
- holders.
The thickness of the tungsten filament that will be used to cut the foam is 0.2 mm. It can be purchased at a specialty store or removed from household appliances. The first step is to install two posts, between which the thread will be stretched. Anyone can do this in a convenient way, which makes cutting easy. Insulators are fixed to the racks, which will prevent them from heating. Springs are mounted to the insulators to ensure constant thread tension. You can connect wires to them that will come from the LATR or from the step-down transformer.
The rheostat is best source than a conventional transformer, since the power consumption, and therefore the heating temperature of the filament, can be easily adjusted depending on the thickness of the foam. A car battery can be used as a power supply if foam cutting is rarely done. In this case, the cutter acquires a certain autonomy and additional safety. It is important for the design to choose the correct length of wire so that it is heated to the required temperature. The process of assembling such a cutting machine is described in detail in the video.
Advice! An interesting cutting device can be made from a soldering iron with a power of 100 W. To do this, it is necessary to dismantle the factory tip and install in its place a thin metal plate or blade, which, when heated, will give an effect similar to a machine tool.
Precautionary measures
In the process of cutting foam plastic, it is necessary to observe certain precautions that will allow you to achieve the best result and preserve the health of the master. One of the rules concerns the use of a shoemaker's knife when cutting foam. Since the movement of the blade occurs in the direction of the human body, it is necessary to remain outside the plane of passage of the knife. In the process of cutting foam plastic, the blade may lock and more force must be applied. If left unchecked, you can cause serious injury to yourself if the blade slips. The knife should have a comfortable handle that is easy to hold in the palm of your hand. This improves cutting accuracy.
Using hand hacksaw and similar tools for cutting foam, you must be careful not to get your fingers into the blade movement area. To do this, you can use a limit bar, which is located next to the cutting line. Before starting work, it is also necessary to check the reliability of fixation of the working surface, as well as the insulation of the power cable. More safe method when cutting foam plastic is to use battery tool. When assembling an electric cutter with nichrome thread, it is better to use a voltage reduced to 12 or 24 volts. If your hand gets on the thread, you will receive a burn; if this happens when powered by 220 volts, you will additionally receive an electric shock.
Summary
As you can see, there are many ways to cut foam, for which almost all available tools are used. Curly trimming allows you to create three-dimensional letters to form names; in addition, when insulating some surfaces it is required figured cut. Thanks to the nichrome thread, it is possible to cut the foam in such a way as to form a box for pipe insulation. For better joining of foam sheets, quarters can be removed at the ends, which will avoid cold bridges.