The Nichrome heating wire is a combination of nickel and chromium metals result into highly resistive nichrome alloy. This alloy has unique property of producing more resistance when current passes through it that makes it to glow red hot. In brief, the thin slice of nichrome wire rapidly heat up on providing the small potential difference to the circuit. It makes the wire suitable for using in the production of fireworks, special polytechnique products and rocket motors to go through the distance safely by pushing the button. There are several changes made in the production of electrical igniters however the basic structure is same. In this article, we’ll study briefly about the nichrome wires used in the igniters.
The nichrome igniter can be designed easily and offers additional safety benefit on the delay made in the fuse. This is the specialty of an igniter to be used for the little powder like rocket motors.
The materials required for making the nichrome wire igniter are short visco protection fuse, nichrome wire of 1.5 inch length and insulation wire is required. The designer can use any kind of insulation wire. Working with the stranded wire is easier and more versatile as compare to the solid wire. Choosing wire with width less than 20 gauge is good to work with. If you want to run the wires over a distance of 20 to 50 feet for the rocket models then the selection of 14 to 16 gauge wire is good. If you want to choose thicker wire, go with lower the gauge wire as it will consume less energy to burn the igniter. The strip of one inch is required to insulate the edges of all wires.
Use the sew needle and piler to push the needle to the edge of the fuse making the perfect tiny hole. The twisted nichrome resistance wire tightly around each of other wires and folded to make it protected. Then the wire is inserted in the tiny hole of fuse and the rest part is connected by twisting the wires and curving them over each other. At this time it should be confirmed that both wire ends are not contacting to each other to make the igniter working properly.
At last the piece is folded over the joints to protect and avoid them to get in touch with each other. On the supply of power in the opposite edges of the wire the little piece of nichrome starts heated up to bright red and ignites the fuse. On the base of the length of wire and thickness of wire, potential difference of three volts will be adequate to initialize the performance of igniter. However the lengthy nichrome heating wire may need large potential difference up to 12 volts and more lengthy wires may require even more potential to start working.
There is also another method to make igniter for which you require: 1.5″ piece of soda straw, 6″ piece of bi-pole insulated copper wire (22-24 awg), 1.5″ piece of 30 awg Ni-chrome wire, Wire cutter/strippers, Soldering iron, Solder, Soldering flux, 6 g KNO3, Epoxy, Magnesium powder and Mixing cup. Following the professional’s guidelines you can make nichrome wire igniter easily.