Preparation Of The Loaded Case To Receive The First-Fire Composition

After the loaded case is taken from the press it is removed to another building, where the case is laid upon a table and an operator reams out by a specially designed tool the excess composition to a depth of 5/8 of an inch from the upper edge of the case. This operation is shown in figure 99.

Reaming excess composition from loaded case.

Fig. 99. - Reaming excess composition from loaded case.

The reaming operation provides room for the first-fire composition which is later rammed into the space so made.

The reamed case is shown very clearly in figure 107. After the above operation five 3/4-inch holes are drilled to a depth of three-quarters of an inch. The purpose of these holes is to aid in making close contact between the composition and the first fire, by helping to hold the first fire in place and by increasing the contact surface. Shellac is then painted on the inside of the case above the composition and immediately the first-fire composition is loaded into place. The shellac acts as a binder, holding the first-fire composition firmly in position.

First-Fire Composition

The first-fire composition is a quick-burning mixture which is used to insure the ignition of the light composition. It is similar in this characteristic to a quick-burning black powder, slightly dampen with wood alcohol.

Drilling holes in composition.

Fig. 100. - Drilling holes in composition.

Lbs.

Percent.

Barium nitrate (Ba(NO2)2)..................

4

44.5

Saltpeter (KNO2).....................

3

33.3

Sulphur (flour)......................

1

11.1

Orange shellac (powdered)...................

1

11.1

9

100.0

Barium nitrate used in this operation is the same as that used in making up the composition light mixture and it is ground to the same degree of fineness. The process of mixing the first-firet composition consists of placing the nitrate of barium in a tub or container. Sulphur (flour), saltpeter and powdered orange shellac are now sifted through a 30-mesh screen onto the barium nitrate. The ingredients are thoroughly mixed by hand and sifted twice through a 30-mesh screen to insure uniformity in mixing. Wood alcohol is added to this mixture just prior to its use, and the mixing and screening operations repeated. The office of the alcohol is to act as a cementing agent since it attacks the shellac and forms a binding composition which hardens quickly. The first-fire composition is placed in position by hand and compressed in place by a hand-lever-operated press. The compressed charge fills the case flush with the top.

This operation is shown in figure 101. Figure 107 shows the first fire piled in the case prior to loading and the compressed charge, respectively.

Priming Composition

The priming composition is a meal-powder quick-burning mixture. Meal powder mixed with gum water sufficient to form a paste constitutes this composition. The gum water is made by adding 2 ounces of gum arabic to 1 quart of boiling water. This priming composition is now painted by hand upon the top of the first-fire composition, as shown in figure 102.

Fuse Match

The object of the fuse or quick match, which is now attached to the priming composition, is to permit a positive and rapid lighting of the priming composition by the expelling charge. The fuse or match for this work is the same as that used for other operations of a similar character. A description of its manufacture is as follows:

Loading first fire in case.

Fig. 101. - Loading first fire in case.

Eight-, six-, five, three-, and two-strand matches are all made in much the same manner. In the manufacturer of five ply, shown in the figure, which is used for the aeroplane, flare, strands from five spools of cotton cord are fed through a port at the end of a tub as shown in figure 103.

The strands are carried downward and along the bottom of the tank, and up the opposite end, passing over a roller, and carried back very nearly to their point of entrance where the group of strands is passed through a groove and over a small wooden sheave. A wiping device suspended from the strings swung across the tank consists of a metal tube of a bore sufficient to smooth down and form into proper shape the surface of the match. During this operation a mixture of meal powder, sulphur, charcoal, and starch, made into a thick slurry with water, is introduced into the tank through which the strands pass, thus soaking the cotton with the powder composition, which is as follows:

Painting prime on loaded case.

Fig. 102. - Painting prime on loaded case.

Per cent.

Saltpeter ..........................

62

Sulphur (flour)....................

14

Charcoal (powdered)...................

20.6

Starch ....................

3.4

1 gallon water

These are mixed by placing the saltpeter, sulphur, and charcoal together in a tub and thoroughly kneading by hand. The whole is then sifted twice through a 30-mesh screen. Ordinary corn-starch is cooked in water and mixed with the sifted ingredients in the tub until a slurry is formed, whose consistency is such that it is not so thick as to ball up on the strands of the cord as they are passed through and yet thick enough to coat satisfactorily. The match as it is drawn from the dipping or impregnating tank is carried onto a winding frame operated by hand.

Match making machine.

Fig. 103. - Match-making machine.