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Skylighter Fireworks Tips February 14, 2008 -- Issue #89 IN THIS ISSUE: How to Make Yellow Glitter Stars 50% Off All Sky Lanterns: Sale ends 2/18/2008 Introducing Ned Gorski Making Nozzle Mix

HOW TO MAKE YELLOW GLITTER STARS

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Photo Courtesy of Tom Handel

Glitter is That Silver Twinkly Part at the Bottom of These Brocade Shells

This is a gold brocade shell. Glitter is hard to depict in slow-shutter-speed fireworks photographs, but you can get an idea of how silver glitter might look like in the sky if you enlarge the photo above.

Here's a good recipe for making yellow glitter from Bob Winokur. Bob wrote the greatest treatise on making glitter stars and comets, Pyrotechnica 2. It's probably the most complete study of glitter stars ever done. This article ran in the August 1992 issue of the First Fire, the Florida Pyrotechnic Arts Guild's excellent newsletter. Thanks to FPAG for letting us use this, and Chris Miller, wherever you are, for writing it.


Yellow Glitter
by Chris Miller-WPA

I originally got this formula from Dr. Winokur a few years ago as a universal (good for all occasions), "state of the art" yellow glitter. It has a long delay and can be used in any sized star, from 1/4" t o 3." Stars 5/8" and smaller tend towards the "glitter cloud" effect and are great in shells by themselves or mixed with color stars in a volume ratio of 3:1 or 4:1 (color g1itter). Stars 3/4" and larger leave long, beautiful tails and are particularly suitable as either regular comets or crossettes.

Assuming the ingredients are lump-free, sieve the mix three times through a 20-mesh screen (window screen works fine) and bind with 8% water. This isn't a lot of water so one should knead it for several minutes to insure that the water is well incorporated. Because of the antimony sulfide, I wear a respirator when mixing the dry ingredients and latex gloves when adding the water (I'm told antimony poisoning is akin to lead or barium poisoning-very unpleasant and I don't want to find this out first hand!)

Priming is not required although some people like to prime them when going for the cloud effect. It is also a good idea to lightly prime the exposed face of crossettes made with this formula because there is a lot less exposed ignition area on a crossette compared to a regular comet of the same size. Priming is cheap insurance against one or two of them being blown blind and diminishing the symmetry of the break (not to mention wasting all that labor that goes into making each crossette that didn't work).

YELLOW GLITTER
Chemical	Parts by Weight
Potassium Nitrate	48
Airfloat Charcoal	9
Sulfur	11
Aluminum (12-20 micron, atomized)	9
Antimony Trisulfide, Chinese Needle	10
Sodium Bicarbonate or Sodium Oxalate	9
Dextrin	4

We STILL have Sky Lanterns literally clogging up the Skylighter warehouse. I kid you not. We need some space! Bad!

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10 White Sky Lanterns $71.48 $35.74
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10 US Flag Sky Lanterns $74.57 $37.29

If you have never seen or used Sky Lanterns, these are some of the most beautiful things you will ever see. They are quiet. They are not fireworks, and are legal almost everywhere. And they are simply beautiful. Everyone who sees them absolutely loves them.

Watch this video clip of 6 Sky Lanterns being launched.

But we just got a truckload of them into the warehouse. And they are literally piled 10 feet high. We need some space.

So, here's the deal. I am putting Sky Lanterns on sale at 50% off for the next 5 days only.

The sale will end midnight, Monday, February 18, 2008. No catch. No fine print.

Normally Sky Lanterns sell for $7 to $10 apiece. But we are putting them on sale for half of that for a very short period of time. So you can save $3.50 to $5 on each Sky Lantern.

We have three types of Sky Lanterns. They are all the same size.

• White Sky Lanterns
  
  
• Colored Sky Lanterns
  
  
• US Flag Sky Lanterns
  
  

Get 'em while they last.

Get your half-priced Sky Lanterns right now.

Musical Birthday Candle

If you have not seen or used Musical Birthday Candles, they are an absolute show stopper! Order your Sky Lanterns early and be sure and get your free Musical Birthday Candles.

INTRODUCING NED GORSKI

I feel very fortunate and honored to announce that Ned Gorski will be working for Skylighter, writing fireworks making articles. Ned's been in this game a lot longer than I have. I first ran into him shortly after I started Skylighter in the mid-'90's. He was a customer, and one whose work I watched more and more closely when we crossed paths at PGI Conventions.

Ned is an unduly humble man. In his letter to you below, he never mentions that his fireworks making skills are right up there on top. He is, in fact a PGI Grand Master. What's that, you non-PGI'ers may be asking?

Every summer, at the Pyrotechnics Guild International's week-long convention, members bring the various fireworks they have made to the nightly competitions. Judges score their entries in different categories (shells, rockets, fountains, etc.). At the end of the competition, the member with the most points is awarded the trophy for Grand Master.

You gotta have mastery of a lotta of different kinds of fireworks to be a Grand Master. Ned has that kind of breadth of experience. I can tell you, we are all fortunate to have Ned sharing his work with us now. He's that rare bird who can walk the walk, talk the talk, and WRITE about it! I hope you enjoy having Ned with us as much as I already am every day I work with him.

Harry Gilliam
------------------------------
Hi,

My name is Ned Gorski. I know quite a few of you personally through the PGI and regional clubs I belong to. If we have not met in person, we may have chatted on the PML (Pyrotechnic Mailing List), or on the club discussion lists, or on Passfire. I sign all my discussion list posts "ned."

Almost 20 years ago I had this urge to find out how fireworks are made. I called Don R., the head fireworker at the big local display company, Rozzi's, and I asked him, "Don, how can I learn how to make fireworks?" I'm sure I sounded like any other newbie to Don, and when he found out that I had no pyro experience, he simply recommended that I join the PGI, read their Bulletins, buy the Best of AFN II, and he wished me luck. But he sounded kind and encouraging.

I did what Don said. I joined both the Ohio Pyrotechnic Arts Guild, (OPAG), and the Bluegrass Pyrotechnic Guild, (BPG. These people enjoyed my efforts, commiserated with me when my devices failed, patted me on the back when they worked, and shared my passion for pyro. I also joined the PGI, and still love reading the PGI Bulletin and its how-to articles. I have enjoyed competing at the PGI convention with my fireworks, and I've been honored to be chosen as the chairman of the manufacturing area at the PGI annual week-long convention.

I am a licensed professional fireworks display operator in the state of Ohio; and I'm an ATF licensed manufacturer. I belong to 3 or 4 regional clubs and I was president of BPG for 4 years.

I've made many different types of fireworks devices over the years, from aerial shells to girandoles and rockets, wheels and gerbs (fountains). Somewhere along the line I discovered places which would cater to my pyro needs, and one of 'em was Skylighter.

I wrote an article for the PGI Bulletin back in the 80's about building aerial fireworks shells using ping-pong balls as the shell casing, based on what I saw when I dissected a Chinese cake. I started that article by with, "Hi, my name is Ned, and I'm a pyro addict."

I jokingly said I needed a pyro 12-step program. The old saying, "Once you smell the smoke, you'll never again be free" is certainly true for me. Once I started working to learn how to make fireworks, I couldn't stop.

To me, fireworking combines two quite different aspects. It is an art form, employing dramatic, aesthetic, effects to evoke an emotional response from an audience. At the same time, fireworks demand precise technical and scientific skills. Art and Science combined.

I have found a community here with all of us 'pyros.' I've made lasting friends with folks who I may only see for one week a year in the summer at the PGI convention, but with whom I may chat almost every day on the pyro lists. And I eagerly look forward to the next event hosted by one of the regional guilds I belong to. Reconnecting several times a year with fellow fireworkers always feels like coming home to my real family.

The motto in fireworking is "Stay Green," synonymous with staying safe. To me that means staying a beginner, ever aware that meticulous care must be taken to achieve a successful pyro endeavor and to avoid the danger and risk that is involved in it. For me, Fireworks is always the Master, and if we are lucky we can have the privilege of participating in that art.

With both my personal fireworks creations and the public displays, I've experienced nice successes, and many setbacks. I've learned something from both along the way, and I intend to share some of those experiences with you. I hope you find them useful, or at least entertaining.

After 30 years as a self-employed builder-remodeler, and with knees that ain't what they once were, when I saw Harry advertising for someone who enjoys fireworking and writing about it, I thought, "That sounds like something I'd really enjoy."

Amazingly, my wife, who always sort of 'tolerated' my fireworks passion, and all the time and energy and money I spent on it, has had a complete change of attitude. Now that she sees me working on fireworks, writing about it, and getting paid a bit to do so, she is starting to see that this just might be an honorable pursuit!

All the best,

Ned

MAKING NOZZLE MIX

If you look in the end of most black powder rockets, or at the end of a gerb (fountain), you'll see a nozzle recessed into the end of the paper tube.



A nozzle is a mechanical device with an orifice (hole) in it, which controls and directs the flow of a liquid or gas as it passes through it. Think of the nozzle you put on the end of your garden hose. It controls the water flow, builds up higher pressure in the hose than would normally be there, and projects the water out in a nice stream. A rocket nozzle does essentially the same thing with the combustion gasses from the motor. This is what propels the rocket skyward.

Typically, the nozzle in a rocket, and the solid plug at the top of the rocket motor's fuel grain, is a rammed (hand pounded with a mallet) or pressed (with a hydraulic or mechanical rocket press) mixture of wax, clay, and grog. Some folks use only clay in their nozzles.

I did that for a while, but found that the clay was very susceptible to shrinkage/expansion, depending on the day's humidity. One time I pressed a bunch of wheel drivers with only bentonite clay nozzles, here in the Midwest hub of humidity. Then, when I got out to Gillette, Wyoming, which was so dry my lips started cracking, my nozzles got so loose in the tubes that I could turn them with my finger. (I quickly added a ring of Elmer's glue where the nozzle met the tube to secure them.)

Some folks expect their nozzle apertures to close a bit with the clay's expansion. So, right before flight, they open the hole up to the correct diameter with a hand-twisted drill bit. Wax makes the clay much less prone to this problem. Also, the clay alone, when pressed, forms a smooth, glossy surface; and nozzles and plugs have been known to get blown out of the tube by the pressure of the fuel burning. The grog in this mix really helps the nozzle 'bite' into the side of the tube and resist blowout.

The grog also helps the nozzle resist erosion of the hole during motor burn, whereas without the grog, the clay can wear away some and the nozzle aperture (hole) opens up some during the motor burn, which reduces pressure and thrust.

The technique I use to formulate these ingredients and mix them together is similar to the one David Sleeter recommends in his Amateur Rocket Motor Construction book.

I get the wax that I like to use from the canning supplies department of my grocery store. It reads "Household Paraffin Wax, for canning, candlemaking, and many other uses." (I'm not sure why they don't list rocket nozzles on the box as one of those uses. ;-)



I either use bentonite clay from Skylighter or Hawthorne Bond Fireclay. They are both very fine, powdered, dry clay. (When I first started making rockets, I imagined that 'clay' that should be like putty, or that I had to turn the dry clay powder into a 'play-dough' by adding water. We live and learn. No water is ever added to the clay.)

Grog is a man-made, sand-like product. It is made from fired pottery, crushed and screened. One well known rocket maker uses crushed red-clay flower pots. Another uses busted up and screened ceramic floor tile. I get my fine-medium grog from my local pottery supply house. Skylighter sells grog which has fine, medium and coarse (up to the size of peas) particles in it. To use that, I screen out the coarse grit to end up with something that looks like fine-medium sand. A fine-meshed kitchen screen colander works well for that.

For a batch of nozzle mix, I weigh out:





Now, I add the clay and grog to a new, clean, one-gallon paint can that I get at Home Depot. After installing the lid, I shake the can to mix the two powders. Then, I open the can, make an indentation in the center of the dry mix, and lay the block of wax in the indentation.



I then lay the lid on the top of the can loosely. (Caution, do not put the lid on tight. Pressure can build up during the heating and either burst the can or pop the lid off, sending wax and clay everywhere, and possibly causing injury.) The can, with the loose lid, is then put in my oven, set at 250 degrees, and cooked for about 1-2 hours or until the wax is completely melted into the dry mix.



OK, OK. So my oven ain't so clean. I'll have to get on my wife, Molly, about that. Yeah, right. Oh, waitaminnit. That's the corn meal and cheese drippings from my pizza cooking on the bottom of it. Never Mind...

I don't use my kitchen oven lightly for this project. In fact this is the only time I do use it in my pyro pursuits-for cooking nozzle mix. I absolutely never use it to dry or heat any pyrotechnic compositions. Never. And I keep the heat in this process down at 250 degrees to prevent the wax from igniting. Puleez, be mindful and careful.

Once the wax has completely melted into the dry mix, you'll see that it has only dampened about half of the clay/grog. The other half is still dry. This is remedied by removing the can from the oven with oven mitts-believe me the whole rig is hot-removing the loose lid, and stirring all the ingredients with a paint stirring stick until the wax is well incorporated into the clay. During this stirring, I only grabbed the can without an oven mitt once.



After stirring the mix with the stick, I install the lid, tightly this time, and, holding the can with oven mitts, shake the can violently to really incorporate the wax into the mix. Then, while the mix is still warm, I open the can and screen the mix through an old, wire mesh, kitchen colander onto kraft paper and let it cool down completely.



This screening process really helps further integrate the wax into the mix, and also removes any waxy lumps which may form, which I just pitch out. The finished Nozzle Mix product will look like a tan, medium grained sand. I put it in an empty 5 lb. plastic chemical tub marked 'nozzle mix.'

I have another tub marked 'bulkhead mix.' This mix is the same as the nozzle mix, but with the grog portion simply replaced with more clay. I use this bulkhead mix in many driver and rocket motors, where I'm not concerned about needing the grog in the bulkhead (top clay plug) to prevent blowout. The advantage to this mix is that I can easily hand-twist a drill bit to create a passfire hole in the plug. If the mix had the grog in it, it would be very difficult to twist the bit through it, and the bit would get very dull quickly.

So, let's pound a nozzle up, remove it from the paper tube, and see just what sort of component this new nozzle mix will produce. Whaddaya say?

Using a Skylighter, one-pound, 1/4" wall rocket tube (TU1068), some one-pound rocket tooling (TL1211), a rawhide mallet (I swear by this mallet), and a 6 x 6 x 4 ft. tall 'pounding post,' I'll pound a nozzle into the tube, using a heaping 1/2 tablespoon measuring spoon and a funnel.

You might notice that black rubber O-Ring (from Home Depot) I like to use around my rocket tooling 'drifts.' Between Skylighter, Home Depot, and the kitchenwares department of my local department store, I get enough stuff to stay busy forever. The O-rings really help keep dust down. But my nozzle mix is not very dusty to begin with.

One nice tip, which I got from Tom D, is to soak the rocket tubes in Minwax Wood Hardener and let them dry. This will strengthen the tubes and make them more fire-resistant. I'll dip the tubes into a can of the hardener, let them set there for a minute, remove them, and stand them on end on some plywood scrap to dry.

Rocket Tooling - Note Black O-Rings

Ram Mix into Tube with Nozzle Forming Tool and Mallet

8-12 nice whacks with the mallet and the nozzle mix is well consolidated. Now, to dissect this nozzle a bit, I use a coping saw to cut the paper tube off right above the nozzle, and slice the tube on both sides of the clay. You can see how the nozzle mix has consolidated into a solid mass, bulging the inside of the tube out just a bit in the process, which really locks the nozzle into the tube.




If you tap a metal spoon against the side of the clay nozzle, it 'tinks' like a little piece of solid ceramic. Nice.

In the future, we'll have an article on how to build a one-pound, black powder, charcoal-tailed rocket based on the foundation that has been laid in this article. One really nice thing about these rockets is that they provide great pyro and immediate-gratification, even in the winter months. Make up some nozzle mix, blend together some fuel, pound a motor together, attach it to a stick, and take 'er outside to fly. Smell the Smoke.

Have fun and Stay Green,

Ned