How To Make Ematches Using Skylighter's Electric Match Heads
The electric match composition that provides this heat sensitivity is called a primer. WARNING: Primers burn and primers explode. Therefore it is important to use as little primer as possible, and then overcoat the primer with another electric match composition that is less sensitive but will take fire from the primer and give a flame spread to the electric match.
Here is a method for making electric matches that produces excellent results:
- First twin lead wires should be soldered to the electric match head. Cut a piece of twin-lead Shooting Wire to length. Split the two leads apart and strip about 1/4 inch of insulation from each lead. Solder one lead on one flat side of the electric match head, and the other lead on the other side. Make sure you solder these to the back end of the electric match, the widest part. This leaves the narrow part, the tip; clear so it can be coated with the electric match composition.
- Coat electric match tip (1/32 inch to 1/16 inch) with primer using the formula below. Allow electric matches to dry approximately 1 hour.
- Recoat with H3/NC or Meal D/NC, one half to two-thirds of the full length of the electric match. Allow drying overnight. NC is nitrocellulose lacquer. H3 is Shimizu's formula of 75% potassium chlorate + 25% charcoal, airfloat. Meal D is a very fine commercial black powder. High quality, ball milled black powder will work, too.
- A final coat of 5% Nitrocellulose lacquer is optional but is recommended.
Primer (also known as Dark Flash)
This formula is well known to be friction and impact sensitive. Therefore it is critical to make and use as little as possible.
Mixing instructions:
- To 5 grams of 200 mesh or finer potassium chlorate, mix a 5% nitrocellulose lacquer solution to achieve a syrupy consistency.
- Add 5 grams of antimony trisulfide (200 mesh or finer) to this mix. Stir gently until a smooth homogenous mixture is obtained. Add more NC lacquer to maintain a syrup consistency. If it starts to harden or thicken, thin it with acetone.
Also be sure to check the continuity of all electric matches with an electric match tester. This is a specially made low-voltage continuity tester that will tell you if your electric match will fire. A standard continuity tester will not work, it generates so much current it will actually fire the electric match. Skylighter electric match testers are roughly the size of a half-dollar. It has a 3-volt lithium battery, which should last five years or more, and a red LED light. The measured current through a typical electric match and lighting the LED is less than 10 milliamps (mA). Although well below the 50 mA maximum test limit, all precautions should be taken. All personnel should be distant from devices under test. Especially if you make your own electric ematches, you should always test your electric matches before attempting to use them.