Stars & Shell Inserts: "Garnitures"
What Are They?
By Ned Gorski
"Garnitures." Kind of an old-fashioned word, not heard very often in conversation. But, as used to describe the class of fireworks components we are about to look at, I'll be darned if I can find a better word.
From "Traditional Cylinder Shell Construction, Part I" by A. Fulcanelli, found in Pyrotechnica IX:
"Garnitures. The general term "garniture" refers to the contents of a shell (e.g., cut stars, pumped comets, serpents, whistles, reports, tourbillions; essentially anything that will fit in a shell."
Pumped-Star Garnitures Filling a Shell-Casing Hemisphere
And, from the dictionary, the root of the word "garniture" lies in the term "garnish," which is defined as "to furnish with beautifying details."
To furnish with beautifying details. Doesn't that sound lovely? That's exactly what we are asking of our various types of garnitures.
There are basically two "sub-assemblies" of a fireworks shell. The first assembly includes the shell leader-fuse, the lift powder, the time fuse, the shell casing, and the burst powder. That whole integrated construct, though, serves one purpose-that of getting the second assembly, the garnitures, up into the air and ignited. Without the garnitures, the shell wouldn't really serve any purpose.
So garnitures refer to the contents of a shell, whether it is used as an aerial shell, a rocket heading, or as an insert in another shell. (In the case of a shell insert to be used inside a larger shell, I suppose the contents of that smaller shell could be referred to as "garnitures of garnitures," or maybe garnitures squared.)
The contents of fireworks mines, and other ground devices-such as cakes, roman candles, and single-shot comets-would also be called garnitures.
Fireworks Stars in a Mine/Mortar Cross Section
Interestingly, as a slight contrast to the definition of garnitures as the contents of a device, many of these components can be attached to the outside of a shell to act as what the Japanese call "Kyoku-do," rising effects.
Large stars attached to the outside of a shell will create a rising tail as the shell ascends skyward. These large rising tails can also be created for rockets by attaching a large comet to the exterior of the rocket motor or heading, to be ignited when the rocket launches.
Scatter-stars assemblies, described toward the end of this essay, may be attached in pairs, Lincoln-Log fashion, on the exterior of a shell, with graduated time-fuse timings. As the shell rises, these stars will spit out to the side, perpendicular to the shell's trajectory.
Small star shells or reports can be attached to a shell to create "ascending small flowers" or "ascending thunder." Or attaching a whistle can augment a shell's ascent.
Although stars are typically the first components that might come to mind as the contents of a shell, when you stop and think about it there are actually many different varieties of shell inserts.
It is an overview of these varieties that I'll be presenting here. Information on how to actually make the different kinds of garnitures will be the subject of future projects.
Taken together, all of these devices comprise the largest and most diverse class of components in fireworks making. A very wide range of construction techniques and fireworks effects is included in this category.
The broad category of garnitures can be subdivided into two parts-stars and inserts. The effects, construction, and manufacturing methods of these two categories are quite different. Generally, fireworks stars are increments of pyrotechnic composition bound into pellets. Inserts are bound in paper tubes, paper sheets, or other types of casings. Inserts may themselves contain stars.
When we picture the traditional "flower" display of an aerial shell, the individual points of light and trails of sparks are created by "stars,"-pyrotechnic composition which has been bound into solid pellets.
Simple firework stars are like small charcoal briquettes, with the composition bound together using a binder such as dextrin, some other starch, or a gum.
I remember the first time I dissected a commercial, consumer fireworks shell 20 years ago (something which has to be done very carefully). Inside the shell I found what looked like seeds coated with black powder-black-powder coated, rice-hull burst-powder I later learned. And there were small chunks of "stuff" which I described as small charcoal briquettes in my notebook. This was my first experience with fireworks stars.
Aerial Shell Bursts of Stars with and without Spark Tails
Virtually an endless array of different effects can be produced by fireworks stars. Most of these effects result from the different compositions used to make the stars. You'll hear star formulas described as "charcoal streamer star" or "color star" or "silver-spark streamer" or "strobe star," etc. These different effects are created from the different chemicals in the composition formulas.
Other star effects are the result of different processes used to make the stars: pumped stars, cut stars, box stars, rolled stars, go-getter stars, etc. Many different effects are dependent on the method that is used to make the stars.
The star effects listed below are created simply from different consolidated compositions, with no tubes or wrappings on them. (Composition-filled tube effects will be described in a minute):
Those are just some of the different effects which arise from simply varying the type of composition that stars are made from, or the star size, and/or the process used to manufacture the stars.
- Single color, non-tailed star, in a wide variety of colors
- Colored star which leaves a spark tail behind it
- Color changing star
- Charcoal star which leaves a trail of orange, charcoal sparks
- Star which leaves silver or yellow metal spark tails behind it
- Unique metal-fueled stars like zinc-granite stars, and electric-spreader stars
- Firefly stars
- Daytime smoke stars
- Crackling stars
- Strobe stars
- Very fast burning stars
- Slow burning stars
- Silver or gold glitter stars
- Small stars which produce a flower with many points of light
- Large stars which produce a few, large, bushy spark trails
Star Manufacturing Processes
When it comes to the different processes employed to make stars, and which can contribute to the variety of the resulting effects, there are three basic methods:
These three methods produce stars with shapes unique to each method:
- Cutting stars
- Pumping stars
- Rolling stars
- Square stars (usually cubic,) made by cutting star composition
- Cylindrical stars made by pumping star composition (although one master pyrotechnist, who is also a master machinist, produces rectangular pumped stars with his special, hand-crafted, rectangular star pump.) Additionally, some folks have experimented with troweling damp, water/dextrin bound star composition into square-divided suspended-ceiling light grids and allowing the cubic stars to dry before ejecting them.
- Round stars (spherical) made by rolling star composition in layers, as jaw-breaker candy is made.
Cut stars are quick and easy to make, and have traditionally been the stars of choice in Italian-American style cylinder shells. No special machines or equipment are necessary to make cut stars. This makes star-cutting relatively inexpensive.
Cut stars can be stacked carefully in ball shells, too:
Cut-Stars Stacked in Ball Shell Hemispheres
Cut stars have sharp corners and edges which make for good star ignition. They "lock together" when filled into cylindrical shell casings, enhancing the integrity and strength of the resulting shell.
Since cut star composition has to be pretty wet to make it suitable for cutting, when the comp is bound with water-dextrin, the resulting stars can take longer to dry than stars made with other methods.
Cut stars also have the disadvantage of not having completely consistent sizes, due to the manufacturing method. So, some of them will burn out before others after the shell bursts. They also do not have a very aerodynamic shape, compared to a round/spherical star; so they do not produce as symmetrical a pattern in the sky as round stars do. Cut stars produce only one single color or effect.
Cut stars do have the advantage of being able to be made in any size batch, from a small 2-ounce batch, up through a 30-pound one. And they can be made and primed all in one single step, rather than requiring multiple layers to be built up, often necessary when rolling stars.
Traditional, cube-shaped, water-dextrin bound cut stars can be made in a couple of ways.
For small batches of cut stars, a "pancake" can be made out of the dampened star composition. This flat pancake is then dusted with star prime, and sliced with a thin, straight-edged knife.
"Pancake" Made into Cut Stars
For larger batches of cut stars, a "loaf-box" can be made and lined with waxed paper. Damp star composition is rammed into the box to form a loaf of star comp, and the loaf is ejected from the box-frame. Slices of the loaf are then sliced off of it, and these slices are then cut into stars in the same way the pancake above was.
"Loaf-Box" for Making Large Batches of Cut Stars
Pumped stars are made by packing slightly dampened star composition into a hollow cylinder, either a single-star pump, or a gang pump called a star plate. The star composition is then consolidated with either hand pressure, hand ramming with a mallet, or with the use of a hydraulic or pneumatic press:
Single Star-Pump, Star-Plate, and Pumped Stars
Typically only slightly dampened, water-dextrin bound composition is made into stars with a star pump. So, pumped stars dry much more quickly than comparable water-dextrin bound cut stars. This is especially advantageous when larger stars and comets are being made.
Pumped stars stack very nicely inside cylindrical shell casings, resulting in strong shell integrity. This is advantageous when large, multi-break cylinder shells are being made.
The use of single star pumps or star plates makes this method of star manufacture a little more expensive than star cutting.
Looking at the photo above brings up a question: What is the difference between a comet and a star? Many fireworkers would describe the large diameter pump above as a comet pump, and the plate as a star plate. The large "puck" could be described as a comet, whereas the smaller pellets could be described as stars.
Technically, any fireworks projectile fired individually out of a mortar would be defined as a comet, no matter what size.
And any projectiles, fired in multiples out of shells or mines, would be referred to as stars, once again regardless of their size.
So, it is the use that pumped projectiles are put to-not their size-which technically determines whether they are comets or stars.
But, in practice large projectiles, as singles or groups fired from a shell or mine, are often referred to as comets. And small projectiles, even if they are fired one at a time, as is done from roman candles, are often called stars.
The bottom line is that it's not always cut-and-dried as to whether a projectile is called a star or a comet. And the distinction is not really important.
Although the pumped stars shown above are pellets made with simple tooling and a single-effect composition, more complex stars and comets can also be made.
Small contrasting-effect stars, such as color stars, can be mixed in with the larger comet composition, such as a charcoal-streamer or glitter formula, prior to pressing the comet. When the comet burns, the color stars stream behind it, mixed in and contrasting with the charcoal or glitter tail trailing behind the projectile. This is called a matrix star or comet.
Pumped stars of different compositions may be glued together to form "married" stars. Often their perimeter is then reinforced with some tape or pasted paper. In this way, a projectile with two different effects can be created, say a blue-headed comet with a gold-glitter tail. This combined effect could not be produced with only one composition.
A color-changing pumped star can be made by using a "cavity pump" to pump a star with a depression in one end of it. Once the star is dry, the cavity is filled with a star composition of a different color or effect. That end is then pasted over with paper or tape. The star begins burning from the solid end, exhibiting one effect, which then changes to a different color when the flame front reaches the inner composition.
Crossettes (splitting stars and comets) are made using only one star composition such as a charcoal-streamer or glitter composition. What makes crossettes unique is that the stars begin flying through the air as a standard star would. But then the individual stars split into fragments which fly off in opposite directions.
These stars are made using a crossette pump. These pumps can either resemble the cavity-star pumps shown above, except with smaller diameter cavity-forming projections on their pistons, or they can have "cross-shaped" projections as shown below.
Crossette Pump with Cross-Shaped Cavity-Forming Tip
After a crossette has been pumped and dried, the cavity in it is filled with either a loose powdered explosive, or with a small "firecracker hole shot." Then the star is pasted with paper except for the solid end. The comet burns from that solid end until the explosive is reached. At that point the projectile splits into fragments, which fly away from each other.
This sudden splitting of all the stars in a shell burst is very surprising and impressive, especially if the stars have been carefully crafted so that they all split simultaneously.
So, you can see that different star pumps, compositions, and construction techniques can create different effects in the sky as the pumped stars and comets fly through the air.
Spherical stars, often called round stars, are made using a star-roller. These stars have an aerodynamic shape and fly through the air in straight trajectories. The stars can be sized during the rolling process in order to create batches of stars which have very uniform, consistent sizes.
Consistent sizing of rolled stars is highly valued because it results in stars which either change color and/or burn out all at the same time.
One of the really significant advantages of rolled stars is that they can be made with one color composition rolled first, followed by a different color rolled on top of that first one. This produces color changing stars.
Different colors or effects are often rolled up in thin layers and allowed to dry between those layers. So the overall star rolling process can be a lengthy one. But, large batches of stars can be made using the rolling method.
Advanced fireworkers can produce stars which change colors multiple times, or start with a color, go dark for a short time, and then flash on with color again, seemingly out of nowhere.
Rolled stars are the staple of the highly artistic Oriental ball shells.
Star rolling begins with cores such as a small cut stars, lead shot, small seeds, or even little pieces of pasta. An advanced technique for starting star-rolling involves "sprit zing" dry, powdered star composition with a water-filled spray bottle, to create cores on which to continue rolling the stars.
Star composition is layered onto these cores using a star roller. The simplest star roller can be a round or flat-bottomed plastic or metal bowl. The bowl is swirled round and round by hand as the star cores are dampened with sprayed-on water, and more dry star composition is slowly added to "grow" the stars as they roll.
Usually, though, a mechanized star roller of some sort is used. A round container of some sort is rotated by a motor as stars are rolled. Plastic or metal drums, large or small bowls, or even rubber tires, are used in various versions of the star roller.
Using a star rolling machine usually makes this method of star manufacture more expensive than cutting or pumping stars.
Different Types of Star Rollers, Commercial and Homemade
So, in summary, simple fireworks stars can be made from basic compositions bound in pellets with binders. Many different effects can be achieved by varying the star formulas or the process by which the stars are made.
But, there is a whole different class of garnitures, normally referred to as inserts instead of stars.
Garnitures Wrapped in Paper
There is a category of garnitures which consists of pyrotechnic compositions wrapped in paper: pressed in paper tubes, layered between sheets of paper, or contained inside paper casings as small shell inserts.
Small insert shells can be used inside larger shells, to create a "shell-of-shells." These inserts can be filled with any of the various garnitures we are discussing, or they can be filled with a report composition to create simple flashes of light and sound when they burst.
Graceful falling leaves stars are made by troweling, like frosting a cake, soft composition between layers of paper. Once the composition is dry, the sheets of paper-bound composition are cut to size, and one end of the falling-leaves is primed to ensure good ignition. These stars softly break out of a bursting shell, and gracefully drift toward the ground looking like colored falling leaves.
Box stars, sometimes called pillbox stars, are made by pressing some dampened star composition into thin-walled paper tubes. The tubes are made by rolling about 4 turns of kraft paper on a ½-inch diameter rod, and securing the edge of the tube with glue. The star tubes are cut ¾-inch long, and a piece of blackmatch is inserted into the tube with the match sticking out of both ends of the tube.
These tubes are then filled with dampened star compositions which are especially suited to these stars. Because of the embedded blackmatch, which takes and holds fire very well, these stars ignite easily and are not blown blind by a hard shell burst. The compositions used to make them burn a long time, and very brilliantly, resulting in a long duration, dramatic display of drooping brilliant-color stars.
Box Star Insert Construction
Hummers sound like their name implies; these tube inserts create a whirring sound which can be accompanied by a spiraling spray of sparks. A fuel composition is rammed between two clay plugs in a strong-walled cardboard tube. Tangentially-drilled vent holes cause the inserts to spin and whir as the fuel burns.
Hummer Insert Construction
Farfalle inserts (plural for the Italian farfalla), called butterflies in English, are constructed identically to hummers, except the two holes are drilled at the same time, on opposite sides of the tube, straight through the center of the tube. This results in a butterfly-shaped spark spray which causes the inserts to wobble and spin erratically as they fly through the air.
Whirlwinds, also called tourbillion inserts, are made in a fashion almost identical to hummers, except the vent holes are drilled in the tube in a way that makes the insert spin end-over-end as it flies through the air, creating a "cyclone" of sparks.
Whirlwind (Tourbillion) Insert Construction
Serpents are another variation on the theme of clay plugs and fuel rammed in cardboard tubes. Instead of vent holes in the tube, though, a serpent has one vent hole through one of the clay plugs, as would a small rocket motor.
An ignition fuse is installed in that hole to ignite the fuel when the insert is ejected from a fireworks device. The resulting spray of gasses and sparks causes the serpent to fly in a serpentine manner through the sky.
Whistles can be used as pyrotechnic inserts. The shrill whistling sound which results from the whistle fuel can be augmented by bright sparks if metal particles are included in the fuel. Whistle fuel is never hand-rammed, only pressed with an arbor press or hydraulic press.
Whistle Insert Construction
Another creative effect can be achieved with scatter stars. These inserts burst out of the shell "blind," with no immediate visible effect at all. Then, suddenly, out of nowhere, dozens of stars appear, shooting every which way in the sky.
Scatter Stars Insert Construction
Go getters create a similar effect when they fly out of a shell burst, except their vibrant colors are visible right away. Then, suddenly, the self-propelled go getters zip in every possible direction.
The method for making go getters is unique in that a liquid form of star composition is squirted out of a plastic squirt bottle into small paper tubes. A small piece of doubled blackmatch is inserted into each go getter, and the inserts are allowed to dry. The bottom end, which is not designed to ignite, is dipped in Elmer's glue to seal it.
You can see that this broad classification, garnitures, includes quite a variety of effects, uses, and manufacturing methods. From the simplest compositions and techniques, such as charcoal-tailed cut stars, to the most complex applications and techniques, garnitures serve a wide variety of purposes in fireworks.
Simply experimenting with and learning about these ways to "furnish our fireworks devices with beautifying details" can keep us challenged for many years in the art that is pyrotechnics.