For those who do not have the ability or desire to use wood carving, outline ornaments tree species to create slotted (cut) carvings on wood and uses plywood as a material, sawing with a jigsaw is not always the most the best option work.
Plywood is a rather fragile material, it can easily break off. And it is often sawed with the formation of unkempt “rags” of fibers on the sides of the cut. In addition, for wood, a jigsaw is not always the best tool, especially if you need to process several similar parts.The length of the working part is selected based on the following considerations: nichrome should heat up to a dark red color when the current is connected. With a lower degree of heating, wood and plywood will be difficult to saw, especially if the board is thick. If the temperature is higher, wood vapors can ignite. Practically, instead of cutting out wood carvings, outline the platbands in in this case burning out comes out.
The design of the tool can be of two types: “fishing rod” and “jigsaw”. In the first case, the tool consists of a wire of a certain length, to the ends of which terminals from the secondary winding of the transformer are attached; in addition, a thread made of Omsk wood is attached to one end; a handle made of a material that does not conduct current and temperature ( better than wood), to the second - a load, the size and weight of which allows you to keep the working part in tension. Instead of a load, you can attach a handle to the second end of the working part.
The second option is a little more convenient to work with and resembles regular jigsaw&ndash wood carving sketches of platbands; The nichrome is tensioned on the jigsaw frame, but the clamps are made of non-conductive material. In this case, the terminals are attached to the wire BEFORE the clamps. The figure below shows how you can tighten nichrome on a jigsaw frame using a special clamping bar. The terminals are fastened after tensioning the wood carvings, sketches, and drawings. There is no need to bring the working part to the state of a “ringing string”, as is usually done with a file. It is better to use a flexible frame, since the length of the working section of nichrome, possibly wood carving sketches of hunters, will have to be adjusted.
The length of the wire in both cases depends on the power of the transformer used. If a length of 100 mm is sufficient for 6V power, then for a higher voltage you will need a longer piece. Nichrome carvings made from bird wood are used since other materials with a small wire diameter will not withstand the required heat.
Nichrome is usually taken with a diameter of 0.3 mm to 1 mm (the diameter depends on the thickness of the layer of material being cut).
The transformer can be used with power from 6 to 24V, the source of the transformer can be old TV, filmoscope or other equipment.
As a candidate for an ordinary hand jigsaw you can use a narrow nichrome wire connected to a step-down transformer. Thus, the length is selected experimentally on a specific transformer. For the convenience of adjusting the length of the working part or restoring it after a break, it is advisable not to immediately cut off a piece of the required length, but simply screw several turns onto one of the contacts, for which you can use bolts and nuts.
Additionally, you need a switch on the wire coming from the transformer - to interrupt the current in the circuit when transferring the wire from one fragment of the drawing to another and when the wire breaks (burns out).
The movements when burning should be of the same type as when cutting with a jigsaw - up and down, but very light, since the cutting speed with a hot wire is much higher than when sawing.
Wooden decorative elements are present in the homes of each of us. Sometimes we go to the store to buy a beautiful wooden frame or a box for home or as a gift to loved ones, friends and relatives. However best gift- this is a gift made with my own hands, and to make beautiful frame or the box we will need a cutter or nichrome jigsaw, which we will do right now.
Watch the video to see how a nichrome cutter is made:
So, to make a cutter we will need a 12 volt 5-10A power supply (you can use a computer unit), nichrome wire with a cross-section of 0.4-0.8 mm (you can disassemble a wire-wound resistor or the same boiler that uses nichrome thread), two pieces of a cut branch , from which we will make handles, copper wire 1-1.5 m long, as well as two nails or two pieces of rigid wire.
The first thing you need to do is take care of the handles. To do this, you need to drive a nail into the pieces of the branch or insert a wire. For convenience, it is better to use a branch from a soft tree. When the wire or nail is inserted, you should take pliers and make rings from the protruding parts of the wire so that the wire itself, as well as the wires, do not slip off when twisted.
The next thing you need to do is take any yellow and black wires from the power supply and connect them to copper wire, which will be the main one in our cutter, not forgetting the need to insulate the wires.
When you plug the power supply into the outlet, it will not start immediately. If you are using older models of computer units, you can install a switch separately by connecting the green wire to any of the black ones. With the new models, everything is much easier: it’s enough to short-circuit the same two wires for a split second using a regular paper clip.
Now it's time for the most important part: choosing the right length. nichrome thread. In order to do this, you can use a special formula, but there is also a simpler method, which is known as the poke method. The required length of thread can be determined by winding it on wooden block, connect the positive wire to one end and gradually bring the negative wire closer from the other end until the thread begins to turn red.
Attention!!! If the length of the nichrome thread is incorrect, the power supply may overload and fail, and the thread may quickly break.
After calculating the length of the thread, all that remains is to cut off the excess part and wind it around two rings of two handles. The wire from the power supply should be wound around the other rings.
Sawing with nichrome wire
Alternative to a jigsaw
For those who do not have the opportunity or desire to use ordinary wood to create a slotted (sawn) wood and use plywood as a material, sawing with a jigsaw is not always the best option. Plywood is a fairly fragile material and can easily break off. And it is often sawed with the formation of untidy “rags” of fibers along the edges of the cut. In addition, for wood, a jigsaw is not always the best the best tool, especially if you need to process several identical parts.
As an alternative to a regular hand jigsaw, you can use a thin nichrome wire connected to a step-down transformer. In fact, instead of sawing, in this case it turns out to be burning.
Tool making
The design of the tool can be of two types: “fishing rod” and “jigsaw”. In the first case, the tool consists of a wire of a certain length, to the ends of which are attached terminals from the secondary winding of the transformer; in addition, a handle made of a material that does not conduct current and temperature (preferably wood) is attached to one end; to the second - a load, the size and weight of which allows you to hold the working part in tension. Instead of a load, you can attach a handle to the second end of the working part.
The second option is a little more convenient for work and resembles a regular jigsaw - nichrome is stretched on the jigsaw frame, but the clamps are made of non-conductive material. In this case, the terminals are attached to the wire BEFORE the clamps. The figure below shows how you can tighten nichrome on a jigsaw frame using a special clamping bar. The terminals are attached after tensioning. There is no need to bring the working part to the state of a “ringing string”, as is usually done with a file. It is better to use a flexible frame, since the length of the nichrome working section may have to be adjusted.
The length of the wire in both cases depends on the power of the transformer used. If a length of 100 mm is sufficient for 6V power, then for a higher voltage you will need a longer piece. Nichrome is used because other material with a small wire diameter will not withstand the required heat.
Nichrome is usually taken with a diameter of 0.3 mm to 1 mm (the diameter depends on the thickness of the material layer being cut).
The transformer can be used with a power from 6 to 24V, the source of the transformer can be an old TV, filmoscope or other equipment.
The length of the working part is selected based on the following considerations: nichrome should heat up to a dark red color when the current is connected. With a lower degree of heating, wood and plywood will be difficult to saw, especially if the board is thick. If the temperature is higher, wood vapors can ignite. Thus, the length is selected experimentally on a specific transformer. For the convenience of adjusting the length of the working part or restoring it after a break, it is advisable not to immediately cut off a piece of the required length, but simply screw several turns onto one of the contacts, for which you can use bolts and nuts.
Additionally, a switch is needed on the wire coming from the transformer to interrupt the current in the circuit when transferring the wire from one fragment of the pattern to another and when the wire breaks (burns out).
Below is a view of the tool, it circuit diagram and the burning process itself.
Basic operating principles
The movements when burning should be of the same type as when cutting with a jigsaw - up and down, but very light, since the cutting speed with a hot wire is much higher than when sawing.
A sample of a product obtained by this method.
Glass, foam, plastic and other materials can also be processed in a similar way.