The very popular fireworks making book, Introductory Practical Pyrotechnics provides a neat project for making sparklers. Problem is, we can’t ship barium nitrate. What to do? Here’s a sparkler project formulae that doesn’t need either barium nitrate or potassium perchlorate. Thanks to one of our readers, who wishes to remain unanimous.
A Sparkler Made with Strontium Nitrate
Strontium Nitrate Steel Sparklers
|Strontium nitrate (CH5543)||200 grams|
|Sparkler-grade (or any other) steel powder (CH8300)||120 grams|
|Aluminum, bright flake, -325 mesh (CH0174)||32 grams|
|Airfloat Charcoal (CH8068)||2 grams|
|Boric Acid (CH8042)||6 grams|
|Dextrin (CH8107)||40 grams|
|+90 ml 25% aqueous ethanol (alcohol) solution|
Grind unground components (if any) separately. Mix together all components except dextrin. Add 25 ml of 25% aqueous ethanol (25% alcohol, 75% water) to dextrin and stir until it becomes a paste. Break up or discard any large clumps that form. Add paste to dry components and stir. Add 65 ml more ethanol solution, with stirring. Dump mixture into 41 mm OD x 12" long test tube (or pipe, whatever). The wet sparkler composition should be 7" to 8" deep.
Dip sparkler sticks (or wire/whatever) into mix and let dry 24 hours. Then apply 2 more coats in same manner. If needed, add about 5 ml ethanol solution to re-wet mix. Let dry 24-48 hours.
The slag from the sparkler dip is fun to let dry in a pile and light on fire on the ground, too.
- You may have to adjust the volume of ethanol solution to make the consistency right; it seems to be slightly more or less every time I do it.
- Sparklers may be difficult to light. Propane torches or those butane cigarette lighters held on for a minute tend to do well. They can also be lit off each other. I sometimes use a prime just for the tip that uses perchlorate [or try a black powder/dextrin slurry].
- When the slag dries, you can notice rust from the steel. This may indicate that coating the steel with linseed oil first may be the way to go, though I haven’t ever had any problems with it. These were made in the Missouri summer, so they had plenty of humidity around.
- The paste can come out a bit clumpy. Larger batches will even out the coatings a bit. I haven’t tried, but thorough mechanical mixing once slurried would probably help, too. It doesn’t affect the sparklers’ burning at all.
I have enclosed a picture of one of these sparklers burning. They burn very nicely, actually a little better than the commercial grade sparklers that one can buy, and they last longer, too. I think this is from a chemistry demo we did in a lab, which is why it’s indoors. Usually I burn them outdoors. Note the safety goggles on the user.
The formula isn’t mine originally–I just modified it slightly. Hopefully this will give you something to tell the people that whine they can’t make sparklers without perchlorates. I’ve actually tried several formulations, including those with perchlorates, and the ones with perchlorates burn too fast, too erratically, and a little too energetically for using as a full coating.
I have found one or two of these perchlorate formulae are useful though, that I will use to coat the tips of the sparklers with just to get them going, since they are easier to light and burn hot enough to get it started.