Salient. Victoria University Student Newspaper. Volume 36, Number 9. 1ts May 1973

Incendiary Mixtures and Igniters and Delays

Incendiary Mixtures and Igniters and Delays

a. General. This paragraph contains examples of easily constructed igniters and incendiary mixtures. A low-order explosion may be obtained by placing some of these mixtures in containers and detonating.

b. Cigarette Delay (fig. 20). Inclose the lighted cigarette in the matchbook or box and surround it with inflammable material such as rags, waste, or shredded paper. American cigarettes burn at the rate of 2.54 centimeters per 7 or 8 minutes in the air.

c. Candle Delay. Surround the candle with inflammable material, such as rags, wastes, or shredded paper.

d. String fuse. If time fuse is not available, it may be improvised as follows:
(1) Wash a shoelace or string in hot soapy water to remove the oil and dirt and rinse it in fresh water.
(2) Dissolve 1 part potassium nitrate or potassium chlorate and 1 part granulated sugar in 2 parts hot water.
(3) Soak the string in the hot solution for at least 5 minutes.
(4) Remove the string from the solution and twist or braid three strands together and permit it to dry.
(5) Check burning rate by measuring the time it takes for a known length to burn.

e. Acid Delay. Acid delays may be constructed In various ways depending upon the material available. The pipe incendiary (fig. 21) delay is one example and is constructed as follows:

(1) Place a tight-fitting copper disk midway in-a pipe.
(2) Fill one end of the pipe with a mixture of 3 parts potassium chlorate and 1 part surgar, then cork.
(3) Fill the other end with sulphuric acid and cork. When the pipe is placed with the acid higher than the sugar chlorate mixture, it slowly dissolves the copper disk, ultimately reaching the sugar chlorate mixture. This mixture produces a hot flame. The thickness of the copper disk, strength of the acid, and the temperature determine the length of delay.
(4) Gelatin capsules, rubber containers, or bottles with rubber membranes are other examples of materials that may be used with acids to achieve delays.

f. Water Can Delay (fig. 22). This device is improvised as follows:

(1) Materials needed.
(a) A bucket-type container.
(b) A float (wood or cork). (c) Small diameter floatmast. (d) Battery.
(e) Electric blasting cap.
(f) Electric wire.
(2) Directions. Make a small hole in the container. Attach the mast to the float. Place a copper wire through the diameter of the upper part of the container with the insulation removed at the center. Prime the charge with an electric cap attaching one lead wire to the stripped end of the wire in the upper portion of the container, and the other lead wire to one of the terminals on the battery. Fill the container with water. Connect a wire from the other battery terminal to the top of the
(3) Functioning. As the water drips from the container the float sinks in the can. When the top of the mast contacts the naked cross wire, the electric circuit is completed thus detonating the cap. Delay depends on the quantity of water and size of the escape hole. Some protection should be used to prevent falling trash, leaves, and other materials from stopping up the hole.
g. Watch Delay (fig. 23). This device Is improvised as follows:
(1) Materials needed—
(a) Watch with celluloid crystal.
(b) Small screw (preferably brass or copper).
(c) Battery.
(d) Electric blasting cap.
(e) Electric wire.
(2) Directions. Drill a small hole one-half centimeter from the center of the crystal and insert a screw. Tighten the screw so that either the hour or minute hand of the watch will make contact but the screw does not touch the face of the watch. If a delay of more than 1 hour is desired, remove the minute hand. Wind the watch and set the hand for the desired delay. Connect one wire to the stem of the watch and a terminal of the battery and the other wire to the screw in the crystal of the watch.
(3) Functioning. When the hand of the watch comes in contact with the screw, the electric circuit is completed thus detonating the electrical cap.

Note

:

Carefully Remove any Finish from Portion of Watch Hand to Touch Screw Thru Crystal to Insure Good Contact. Short Pieces of Cap Lead Wire may be used to make Illustrated Connections.

Figure 19. Improvised thermite grenade.

Figure 19. Improvised thermite grenade.

Figure 20. Cigarette delay.

Figure 20. Cigarette delay.

4,300 cubic feet (123 cubic meters) wheat flour 10 pounds (45kg) Wooden building 4,300 cubic feet (123 cubic meters) coal dust 10 pounds (45kg) Wooden building 18,500 cubic feet (524 cubic meters) wheat flour 100 pounds (46kg) Wooden building 450 cubic feet (13 cubic meters) Gasoline 6 gallons (23 litter) Room 159,000 cubic feet (4,503 cubic meters) Gasoline 30 gallons (115 litter) Building 88,000 cubic feet (2,492 cubic meters) Gasoline 2½ gallons (10 litter) Cold storage romm

Tabele I. Dust Initiator, Size of Building vs. Amount and type of Cover Charge.

Figure 21. Incendiary delay in pipe.

Figure 21. Incendiary delay in pipe.

Figure 22. Water can delay (electric).

Figure 22. Water can delay (electric).

Figure 23. Watch delay device (electric).

Figure 23. Watch delay device (electric).