Why Make 2-Ounce Black Powder Rockets?

While these rockets are similar in scale to a consumer-fireworks black powder rocket, the motor is larger, and the aerial display is more impressive.

Yet, they are still small and quiet enough to be launched anywhere a standard black powder rocket would be safe to fly. You will be making a nice, backyard-scale rocket in this project.

Equipment Needed

Get the following items together before starting (items in blue are supplied in Skylighter's 2-Ounce Black Powder Rocket Kit):
  • Potassium Nitrate

  • Sulfur

  • Airfloat Charcoal

  • 80-Mesh Charcoal

  • Bentonite Clay

  • Fast yellow Visco fuse

  • Green Visco fuse

  • Rocket tooling

  • 2-Ounce rocket tubes (3/8" ID x 3.5" long parallel tubes)

  • A blade-type coffee fill (Walmart's are fine)

  • A mallet with a non-metal head (plastic, rawhide, wood, etc.)

  • A 20-mesh screen

  • A 40-mesh screen

  • A small brush

  • An awl

  • Kitchen measuring spoons

  • 1/8-inch drill bit

  • A spray bottle

  • A scale for weighing in grams or fractions of an ounce

  • Some paper cups

  • Some plastic tubs

  • A pencil

  • A Sharpie marker

  • Masking tape

  • Newspaper or kraft paper

  • Plastic kitchen gloves

  • 12-Inch bamboo skewers

  • Plastic zip-loc baggies

  • A heavy, hard surface to ram on (a 6-8" square/round ramming post is best)

  • Optional: flying fish fuse, stars, titanium powder, or ferro-titanium powder for "headings"

The Black Powder Rocket Fuel

This project uses a hand-mixed black powder that contains the three components of traditional black powder: potassium nitrate, charcoal, and sulfur. It requires no ball mill or expensive equipment to make it.

WARNING: You're about to make one of the most common, yet powerful, pyrotechnic compositions used in fireworks. Observe all safety steps as you go along:
  • Minimize the exposure of this composition to any possible ignition source whenever possible.

  • Store the mixture safely, away from any possible source of ignition and keep the containers tightly closed when not in active use.

  • Have a healthy respect for it.
Watch what happens when just one teaspoonful of this black-powder rocket fuel is laid out in a line 8-inches long and ignited. If you are in close proximity to a large quantity of this powder when it ignites, you will not have time to escape the fireball. Advance preparation is the only way to avoid serious mishaps when working with energetic compositions. You will never be able to outrun an accidental pyrotechnic ignition.

Homemade black powder burn test.

Mill the Potassium Nitrate and Sulfur (Only)

A simple method for grinding individual chemicals very fine is to use a small blade-type coffee mill. Never grind mixtures of chemicals in a coffee mill because they can ignite or explode.

The coffee mill can efficiently grind 3 ounces of the potassium nitrate at a time, and 1.2 ounces of the sulfur at a time. It only takes 10-20 seconds for each batch. Milling may go faster if you hold the mill in your hands and shake it while milling.

Make sure to mill them enough that they are fluffy fine. Store these individual milled chemicals in their own plastic baggies or tubs, segregated from the unmilled chemicals.

Grinding granular potassium nitrate into a fine powder using a coffee grinder.

Note: Small inexpensive coffee mills like those from Walmart can overheat if you run them too long. Once they overheat and stop working, they won't work again. Use short 5-10 second pulses, and let the mill cool down before milling any more.

Airfloat charcoal is fine enough to be used as is, so you don't need to grind it in the coffee mill.

Do not mill the 80-mesh charcoal.

Mixing Black-Powder Rocket Fuel

Since it can be a little cumbersome working with large batches of rocket fuel, I suggest you make 8-ounce batches.

8-Ounce Batch of Black Powder Rocket Fuel

Chemical Percentage 8 Ounces 228 Grams
Potassium nitrate 0.60 4.8 ounces 137 grams
Airfloat charcoal 0.12 1.0 ounces 27 grams
80 mesh charcoal 0.20 1.6 ounces 46 grams
Sulfur 0.08 0.6 ounces 18 grams
Total 1.00 8 ounces 228 grams

First, weigh out each individual chemical (for an 8-ounce batch) into its own paper cup. Then dump all of them into a plastic mixing tub. With the lid on tight, shake the chemicals to mix them together, holding the lid down while you do.

Then open the tub, and pass the mixture through a 40-mesh screen into another tub. Work the composition through the screen with your gloved hand.

Cap that second tub and shake the contents again. Repeat the shaking and screening process three times to ensure the chemicals are completely mixed.

Note: Mixing and screening this chemical mixture is a dirty process. It's best done outdoors wearing a dust mask. This is now a very flammable, potentially explosive composition and needs to be treated with respect, keeping it away from all sources of sparks and flames.

Weighing out chemicals for making black powder and screen mixing the chemicals together.

Dampening, Granulating, and Drying Rocket Fuel

Once again, do this outdoors to minimize dust contamination and wear gloves. Spray water into the base-mix composition, and work the water into the powder with your hands.

Spray one ounce of water (either a fluid ounce by volume or an ounce by weight--they're both the same) into the 8-ounce batch of powder. Work it in with your hands. Then press the dampened composition through a 10-20-mesh screen.

Dampening and screening black powder rocket fuel
Dampening Rocket Fuel with Water, Working It through a 20-Mesh Kitchen Colander

Spread the dampened composition out evenly on a paper-lined tray. Place in a safe, warm place to dry, ideally outdoors. In a warm and lightly breezy location the mixture will usually dry in a few hours. But, if there is too much wind, the paper and mix will fly off your tray, ruining your hard work.

Wetting homemade black powder, granulating the powder through a screen and then drying it on a paper lined tray.

Once it is dry, work the powder through the 10-20-mesh screen one more time to break up clumps. Then put it into a sealed plastic container. Your black-powder rocket fuel is now ready to use.

Using a Sharpie marker, label the fuel in that tub and keep the fuel in the tub during rocket construction, opening it only to remove each necessary increment of fuel.

Ramming a Clay Nozzle in a Paper Tube

The first step in actual rocket construction is ramming a clay nozzle in the motor tube. Assemble your materials: clay, rocket tooling, a (wood, rawhide, plastic or other non-metallic) mallet, ramming post, 1/4-teaspoon measuring spoon, paper tube, and an awl.

Note: Clay is rammed dry. It will tightly pack into a solid mass during the ramming. Never dampen this clay.

If you are using Skylighter's 3/8" combo-tool, place the tube on the longest spindle on the tooling base. The long spindle will create a hole through the clay rocket nozzle, and a core up into the rocket fuel grain. The large fuel surface area created in this core will ignite instantaneously and produce large amounts of gas quickly, which will propel the rocket into the air.

Install the ram-through funnel on the top of the paper tube. Scoop out a slightly rounded 1/4-teaspoonful of the clay and dump it into the tube through the funnel.

Insert the hollow ram-drift, and slide it up and down in the tube a few times to completely settle the clay to the bottom of the tube. With the spindle base on the ramming post, gently use your mallet to ram (hammer) the hollow drift 6-8 times mallet until the clay nozzle feels completely solid.

Remove the drift from the tube and clean any clay out of the hole in the drift with an awl.

Holding the spindle base and tube in one hand, tip them over and gently tap any loose clay out of the tube back into the container of clay.

There is now a nice, solid nozzle formed in the rocket tube.

Ramming the Rocket Fuel

Before you begin ramming any fuel, you will need to mark your hollow and solid rammers. You have to do this, so you will know when to switch from the hollow ram to the solid one. This is to prevent you from ever hitting the spindle with your solid ram when you are ramming fuel.

Note: "Pinching" fuel between the top of the spindle and the end of the solid rammer can cause an explosion. So, preventing that from occurring is extremely important.

Insert the solid rammer (also called a "drift") all the way into the paper tube until it contacts the tip of the spindle. Put a little pencil mark on the drift right at the top of the paper tube. Then pull the drift out of the tube and put another pencil mark on the drift about 1/4-inch below the first one. This second mark is the "no-pass" point beyond which the solid spindle is never rammed into the tube.

Why make the second mark below the first one? Why not just change from hollow to solid rammer right at the top of the spindle?

The second mark allows you to use the hollow drift to ram fuel to a point 1/4-inch above the top of the spindle. You do this to avoid "pinching" the fuel directly between the solid rammer and the top of the spindle.

Warning: "Pinching," the rapid and high compression of pyrotechnic composition directly between two metal parts, can cause fuel to accidentally ignite. That extra 1/4 inch of fuel creates a safety buffer to prevent pinching the fuel.

Remove the drift from the tube. Wrap a piece of masking tape around the drift with the bottom edge of the tape where you made the second/bottom pencil mark (at the no-pass line).

Marking rocket tool drifts with masking tape no-pass lines.

Now put a mark 1/4-inch up on the solid drift's no-pass masking tape. This is where the top of the tube would be if the drift was inserted all the way until it hit the spindle.

Warning: Never ram your drift further into the tube than the "no-pass" edge of the tape. This will prevent the drift from ever contacting the spindle and prevent accidental ignition of the rocket.

Align the bottoms of the solid and hollow drifts and put a mark on the hollow drift alongside the mark you just made on the solid drift's tape. Wrap a single layer of tape around the hollow drift with the bottom of the tape aligned with the mark on it.

The bottom of the tape on the hollow drift marks how far that drift is inserted into the tube when the end of the drift is even with the top of the spindle.

When fuel is being rammed in the tube, the hollow drift must be used until that edge of the tape is at or above the top of the tube. That indicates that fuel has been rammed to, or slightly above, the top of the spindle. Then you can switch to the solid drift to ram the remaining fuel and the clay bulkhead.

Note: If your hollow drift will not slide into the paper tube with this piece of tape on it, use the black Sharpie marker to make a mark where the bottom of the tape is, and remove the tape. Keep an eye on the Sharpie mark as you are using the hollow drift, and refresh the mark as it gets worn off.

Dampening and screening black powder rocket fuel
Marking Hollow Drift with Masking Tape

Load 1/4-teaspoonful of the fuel into the paper tube through the ram-through funnel. Using the hollow rammer, consolidate the fuel with 6-8 whacks with the mallet.

Repeat this with increments of the fuel until the mark on the hollow drift is even with, or slightly above, the top of the tube after an increment is rammed.

Switch to the solid rammer and ram two increments of fuel, making sure the no-pass line never goes into the paper tube. This should bring the no-pass line to about 1/4 inch above the edge of the tube after the final fuel increment.

Since the no-pass line would be in the tube 1/4 inch if the solid drift was in contact with the tip of the spindle, when that line is 1/4 inch above the tube's edge after ramming a fuel increment, there should be 1/2 inch of fuel rammed above the spindle.

That amount of fuel above the spindle will create a "delay" time as the rocket flies upward before the "heading" is ignited.

The fuel above the spindle burns more slowly than the fuel below it did, and creates a coasting, delay portion of the flight.

Once that delay fuel has burned, the heading will be ignited. The heading, if you have installed one, is the effect attached to the top of the rocket motor, designed to create a visual and/or audible fireworks effect at the end of the rocket's flight.

Place the excess fuel back into the plastic container and cap it tightly. Remember to always minimize the amount of exposed fuel.

Ramming a Clay Bulkhead

After the fuel has been rammed to 1/2-inch above the tip of the spindle, as described above, ram a 1/4-teaspoon increment of clay to form a bulkhead in the top of the rocket motor.

Optional: Adding a Heading to the Rocket Motor

Various types of headings can be added to one of these rocket motors to create some fireworks effect at the top of its flight.

I suggest you omit the heading completely for your first test flights. In that case do not drill the bulkhead passfire hole.

If you do want to add a heading to your rocket, you could use some 3/4-inch pieces of flying-fish-fuse. Or you could use some loose powder, such as the same black-powder rocket fuel you used to make the motor. A pinch of titanium or ferro-titanium in that loose rocket fuel would produce a spray of sparks to accompany the heading's "pop" at the end of its upward flight.

But this project will show you how to use 3/8-inch pumped stars in the heading.

Drill a Passfire Hole through the Bulkhead

After the delay fuel has burned up, in order for the rocket motor to pass fire to the heading, a hole must be drilled through the clay bulkhead.

Warning: You are drilling directly into a pyrotechnic composition once you get through the bulkhead clay. You must do this slowly with a drill bit twisted by hand. Do not use a power drill to do this. Make sure no open batches of fuel are in the vicinity when this operation is undertaken. It is best to do this drilling outdoors.

Use a 1/8-inch drill bit and center the bit in the face of the clay bulkhead. Gently twist the bit by hand, drilling into the clay and keeping the bit perpendicular to the bulkhead face.

Drill all the way through the clay bulkhead and just penetrate the fuel grain about 1/16-inch.

Dump all the loose clay out of the passfire hole so it doesn't obstruct the fuel.

Hand ramming a 2-ounce black powder rocket.

Adding the Heading

The first step in adding a heading to the rocket motor is to cut a 1/2-inch piece of yellow, fast Visco fuse and insert it all the way into the bulkhead hole until the fuse bottoms out against the fuel.

Then install the ram-through funnel and fill the void in the end of the motor tube, around the fast Visco fuse, all the way to the top with loose rocket fuel as shown in the photo sequence below. Remove the funnel.

Then, balance one, three, or more stars on the end of the tube, and wrap the stars with two turns of masking tape.

Seal the masking tape against the motor tube tightly. Then put two more tight turns of tape around the tape on the motor tube to firmly attach the wrap to the tube.

Loosely fold the masking-tape wrap over the top of the stars. Put one small piece of tape over that end to hold the stars in place.

The idea is to have the stars ejected out of the end of the heading tape enclosure after they are ignited by the burning, loose rocket fuel.

Attaching 3/8-inch pumped firework stars to a 2-ounce black powder rocket as a rocket heading.

Finishing the Rocket

To finish the rocket, use two 5-inch long bands of masking tape to attach a 12-inch bamboo skewer to the side of the motor. Lap the stick up onto the side of the motor about 2.5-inches. Keep the stick straight in alignment with the motor as you attach it.

The purpose of the stick is to act as a stabilizer to keep the rocket flying in a relatively straight line.

Insert a 4-inch long piece of Visco ignition fuse into the hollow core of the motor, and push the fuse in as far as it will go. Tape it to the stick if necessary.

If you wish to, a 3-inch by 5-inch piece of colored tissue or gift-wrapping paper can be glued around the motor to give it a finished look.

Putting the finishing touches on a homemade 2-ounce rocket. This includes attaching the rocket stick, fuse and adding a decorative paper wrapping.

The Finished Product

It's hard to find tall, glass pop-bottles anymore, which were ideal for launching black powder rockets. But, any piece of pipe, a foot or two long, will serve as a launching tube for these 2-ounce black powder rockets.

Anchor the tube solidly into the ground or into a hole drilled into a block of wood to serve as a base.

Insert the black powder rocket with the Visco fuse hanging outside the top of the tube, light the fuse and retire to a safe distance to enjoy the rocket's flight.

Day time launch of a homemade 2-ounce black powder rocket. Includes slow motion replay.

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