Pillbox star

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Pillbox star
Pillbox star

A pillbox star is a small thin walled cardboard tube filled with pyrotechnic composition that has been pressed by hand, with a fuse running through it. This is to allow the use of different compositions that might normally be blown out when the star is flying through the air at high speeds. Their effect is quite different compared to pumped stars or rolled stars and usually have a longer burning time. It burns from both ends and produces a larger flame envelope (visible burning area).


[edit] Materials

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Casing
Thin walled paper tubes are used as a casing. Under no circumstances be tempted to use materials other than paper. It is dangerous and unnecessary. It is more cost beneficial and easier to roll your own paper tubes as outlined in this tutorial, however you can buy them if you wish. Rolling your own tubes enables you to achieve the exact dimensions required for your intended application. Typically the tubes are 1 to 1 1/2 inches long and have a 3/4 inch diameter.

Tools
A 3/4 inch rammer or wooden dowel are needed for rolling your tubes. You will also need kraft paper, white glue and black match or visco fuse.

Composition
There are several pillbox star compositions that can be used. In this tutorial we will be using pillbox star mix red (lancaster) and it is assumed you have prepared your preferred composition in advance.

[edit] Construction

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First step is construction of the casing (if you already have a pre made casing then skip this step). Cut a length of paper about 10cm long and place this on a flat surface. Now take your rammer or wooden dowel and roll the paper around it until you achieve 1 revolution. Place some white glue on the paper near the rammer (see picture) and continue rolling for another 1 revolution. Your biggest problem will be telescoping. That is, as you continue to roll, the paper tape will start to run off to one side or the other. If this happens carefully unroll and start again. Add some more white glue to the paper in a zig zag shape and roll the paper until you have about 1 cm remaining. Place a small line of glue close to the edge and finish rolling the paper. Hold it in your hand tightly for 30 seconds or until the glue has set and the paper does not undo when you let go. You can add a small piece or paper tape to the edge if you wish to aid this process. Remove the casing from the rammer and set aside to dry.

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Next step is to cut black match long enough so that half an inch hangs out the sides. For example, if your tubes are 1 inch long then cut 2 inches of black match. When the tube has been filled with composition the exposed black match ignites and burns the composition from both ends of the pillbox star.


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Insert a length of black match into a tube and gently fold it over the ends. Hold the match in place with your fingers and scoop up some of your composition. Gently squeeze the composition together with thumb and index finger; however don't compress the composition too much. The idea is to fill the tube with slightly compressed composition so it will burn faster.

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Once the tube is full set aside and repeat the process again. As the pillbox star is much thicker than a standard star it will take a few weeks to dry out completely. It will appear dry in a couple of days however it will still be damp in the inside. Don't speed dry your stars as it will cause the composition to crack.

[edit] References

Wouter Visser

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