The Science Behind T-Shirt Cannons

T-shirt cannons are a fun way to promote your team or company, but how do they work? T-shirt cannons use compressed gas, usually carbon dioxide, that is delivered into an air tank. When the trigger is pulled, the gas is released, and the energy shoots whatever is in the barrel—in this case, a rolled-up T-shirt. T-shirt cannons can be made from PVC, batteries, and switches, and can also be purchased ready-made. They have evolved from the slingshot era, where mascots used enormous rubber bands to launch shirts into the crowd, to now weighing as little as two pounds and being able to fire up to 100 metres.

T-shirt cannon history

The T-shirt cannon is believed to have been invented by Tim Derk, also known as the Coyote, the mascot for the San Antonio Spurs basketball team from 1983 to 2004. During his time as a mascot, Derk was always looking for ways to improve the live game experience for fans. Mascots would often throw out free merchandise, including T-shirts, to the crowd, but their throwing range was limited.

In the 1990s, Derk and his peers decided to design and build a device that could launch T-shirts further into the stands. The first T-shirt cannon was a 90-pound cast-iron pipe, 4 feet in length, that used compressed air and the pneumatic principle to blast T-shirts into the crowd. Derk debuted the cannon during a game, dressed as "Rambote"—a combination of Rambo and the Spurs' Coyote. The new invention was a hit, and soon other mascots began adopting the T-shirt cannon.

The concept of using compressed air to launch projectiles can be traced back to World War II. During the war, sailors on commercial freighter ships were left vulnerable after their anti-aircraft weapons were rerouted to warships. To protect themselves, they adopted a weapon developed by the Department of Miscellaneous Weapons Development called the Holman Projector, which used steam from the ship's boiler to shoot projectiles out of a tube. While the sailors primarily lobbed grenades in this manner, they also used less-lethal ammunition, such as potatoes, when they weren't under direct threat.

The T-shirt cannon has evolved significantly since its inception. Kenn Solomon, the Denver Nuggets' mascot, helped design some of the first T-shirt cannons that were sold commercially. Today, T-shirt cannons are much lighter and more advanced, weighing as little as two pounds. They have also become more versatile, with mascots loading them with various items such as hot dogs, popcorn, confetti, and even stuffed toys.

Safety considerations

T-shirt cannons are powerful tools that can be used to create excitement at events, but they also have the potential to cause injury if not used correctly. Here are some safety considerations to keep in mind when operating a T-shirt cannon:

Training and Supervision:

It is important that anyone operating a T-shirt cannon receives proper training on how to use the device safely. This includes understanding the mechanics of the cannon, as well as knowing how to load and fire it correctly. Adult supervision is recommended, especially when minors are involved.

Eye and Face Protection:

T-shirt cannons can generate significant force when fired, and it is important to protect the operator and bystanders from any debris or projectiles that may be discharged. Safety glasses or goggles should be worn by the operator and anyone standing nearby to protect against eye injuries.

Safe Distance:

Always maintain a safe distance between the cannon and the target. Do not fire at targets that are too close or within a crowded area. A minimum distance of 30 feet is recommended to ensure the safety of both the operator and the intended recipients.

Proper Ammunition:

Only use approved ammunition with your T-shirt cannon. This includes items such as rolled-up T-shirts, stress balls, soft toys, and other similar objects. Do not use hard or sharp objects that could cause injury. It is important to ensure that all items are securely rolled and fastened with elastic bands to prevent them from unfurling in the barrel or during flight.

Regular Maintenance and Inspection:

T-shirt cannons should be regularly inspected and maintained to ensure they are in safe working condition. This includes checking for any signs of wear and tear, leaks, or damage to the cannon. All connections and fittings should be secure, and any necessary repairs or replacements should be made before use.

Risk Assessment:

If using a T-shirt cannon at a public event, it is important to conduct a thorough risk assessment to identify potential hazards and implement control measures. This may include considering the venue, the number of people present, the experience of the operator, and any other relevant factors. A risk assessment template can be obtained from certain suppliers, who can also provide advice on how to complete it.

Safe Handling of Gas:

T-shirt cannons that use compressed gas, such as CO2, require careful handling of the gas cylinders. Ensure that you are familiar with the proper procedures for transporting, storing, and connecting the gas cylinders. Always follow the manufacturer's instructions and safety guidelines when handling compressed gas.

How to roll a T-shirt

To roll a T-shirt for use in a T-shirt cannon, first open the T-shirt out and fold it in half, lengthways. Then, fold it in half again, lengthways. Start to roll the T-shirt from the neck, pulling on the open length of material to tension the roll. Once it's rolled up, secure the T-shirt with at least two strong elastic bands. The T-shirt needs to be rolled up tightly and secured with strong elastic bands so that it will hold together in flight and doesn't open up and flutter down a few meters from your feet!

T-shirt cannon design and construction

T-shirt cannons are a fun way to promote your team or company at events. They are designed to shoot out promotional items such as t-shirts, hot dogs, and toys into a crowd. The design and construction of a T-shirt cannon involve several key components and steps.

Firstly, the materials used for the cannon's construction are important. PVC pipes and fittings are commonly used, with various diameters and lengths depending on the desired size of the cannon. Other materials include pipe caps, couplers, reducers, valves, adapters, hoses, and epoxy.

The construction process begins with drilling holes in the pipe caps to accommodate valves, nipples, and adapters. The pipes and fittings are then solvent-welded together to form the barrel and air tank assemblies, ensuring that the diameters are reduced to fit the solenoid valve openings. Iron pipe nipples are used to connect the solenoid valve to the PVC fittings. It is important to apply pipe-thread sealant to prevent leaks.

The firing mechanism can be electrical or use compressed air. For an electrical setup, batteries, switches, and wiring are required. For compressed air, a bike pump or air compressor is used to fill the tank to the desired pressure, typically around 40 psi.

To fire the cannon, a tightly rolled T-shirt is inserted into the muzzle and pushed to the bottom of the barrel. Safety precautions, such as wearing protective eyewear, are essential. The air tank is connected, pressurised, and aimed before firing.

It is important to note that PVC weakens in cold weather, and overpressurising the tank can be dangerous. Always test for leaks and ensure a safe distance from targets.

T-shirt cannon operation

T-shirt cannons are a fun and unique way to promote your team or company, often used at sporting events. They are also known as air cannons, and the basic principle behind their operation is the use of compressed gas, usually carbon dioxide (CO2), to launch t-shirts or other items into a crowd.

To operate a T-shirt cannon, you will need to prepare the t-shirts by rolling them tightly and securing them with rubber bands or elastic bands. This ensures that they will fly straight and not open up during the flight. The rolled-up t-shirts are then loaded into the cannon's barrel, which is typically made of PVC or metal. Some cannons may have a magazine that can hold multiple shirts, allowing for rapid firing.

The compressed gas, such as CO2, is stored in a tank attached to the cannon. When the trigger is pulled, the gas is released, creating a burst of energy that propels the t-shirt or other items out of the barrel and into the air. The pressure of the gas can be adjusted to control the distance that the items are launched. It is important to follow safety instructions when operating a T-shirt cannon, as improper use can cause injury.

To build your own T-shirt cannon, you will need PVC pipes and fittings, a solenoid valve, a tank valve, a compressor or foot pump, batteries, switches, and other hardware. The PVC pipes and fittings are solvent-welded together to create the barrel and air tank assemblies, with iron pipe nipples connecting the solenoid valve to the PVC fittings. A circuit is then built to control the launch, using batteries, a toggle switch, and a push-button trigger.

Overall, T-shirt cannons are a creative way to engage with audiences and promote your brand, but it is important to operate them safely and follow instructions to avoid any potential hazards.

Frequently asked questions