Working with Aerotechnic™ Cannons
You should be aware that, in order to get the most out of your cannon, you'll need to purchase several accessories in addition to confetti and/or streamers. The first of these, the CO2 cartridge, is necessary for the cannon to work at all. The description of each cannon will specify what size CO2 cartridge it uses. Do not try to use a cartridge of a different size, as too small a cartridge won't push the confetti out of the barrel, and too large a cartridge will be a waste of money (it won't make the load travel any further) and could conceivably even crack the barrel of your cannon.
In addition to using the correct size, you should only ever use Theatre Effects brand cartridges. We often get inquiries as to whether or not commercially available CO2 cartridges (often sold for use with air rifles and paintball guns) will work in our cannons. I assure you, they will not work. The commercially sold cartridges are almost always a smooth-neck cartridge, while our cannons are designed to work with threaded cartridges; in addition, the metal used to seal a commercial cartridge may be thicker than that used on ours, resulting in damage to the firing pin.
A cannon loaded with confetti and fitted with the proper size CO2 cartridge will produce an effect, but it may not be as big an effect as you'd hoped for. To get the best possible shot, you should always use a lifting cup and backpressure cap. The lifting cup is a cardboard device that fits snugly in the barrel of the cannon, forming an airtight seal. The cup is then pushed to the bottom of the barrel with a ramrod, and the confetti and/or streamers are loaded on top of it. The lifting cup acts much like a piston; the CO2 released from the cartridge pushes against the cup and it pushes the load out of the barrel. Without a lifting cup, much of the CO2 released would simply escape around the load without doing any actual work.
The backpressure cap is also a cardboard device, this one designed to fit snugly over the end of the barrel. The backpressure cap is taped in place with masking tape, and prevents the CO2 from escaping. Once sufficient pressure has built up behind the cap, the tape will break and the shot will be released with a loud "pop!" Without a backpressure cap, or if the cap is poorly secured, the shot will not go as far and there will be less noise as it's released.
You can assume a 20% reduction in shot distance if you do not use a backpressure cap, and a further 20% reduction if you don't use a lifting cup. For some shows or venues, this may be desirable, but most directors are looking for the biggest effect that can be created with the cannon. As with the CO2 cartridges, you'll need to make sure you purchase the correct size caps and cups for your cannon. The description for each cannon will list the barrel diameter (usually 1" or 2") and this is the size you'll use when ordering these accessories.
Finally, users are sometimes concerned about the possibility of the backpressure cap or lifting cup flying out into the crowd. Rest assured that, while this may happen, both devices are light enough that they are unable to cause any harm to an audience member. The only real danger from a cannon like this would come from loading it with heavy, hard or sharp objects. As always, a little common sense and planning will go a long way towards preventing any mishaps during your performance.
Theatre Effects Customer Service Department
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