Hey guys so basically this is the year our team wants to go from meh to great. Our first objective was naturally sponors. We had 0 sponsors in the beginning of the season and now we have 4. The unforunate thing is we have money now but we need mentors and sponsors with machining facilities ad stuff of that nature.
So to attract those kind of sponsors we need to make something cool and something that can be used for event. We are also sponsored by cablevision now which owns madison square garden. Sooooo naturally t-shirt cannon is the idea that comes to mind.
we have a drive train from I think 2010 that we are going to outfit with the new control system or just redo the wiring. Its just a standard kop chassi which is fine. The issue is the cannon itself.
I saw a thread a while back with someone saying they would give a parts list. we have a bit of phenumatic experience and have supplies its just the speciallty stuff and how it works.
It also cant completely break the bank. We have some money (1,100) and we were going to spend it all on supplies but we can get away with 750 in supplies leaving $350 for parts for the t-shirt cannon.
You can make a really cheap and easy setup using a sprinkler valve. That’s what we’ve been doing since we first built a t-shirt cannon. Basically you would store compressed air in a tank and then run a house to a sprinkler valve which would be attached to the back end of the barrel. The valve is triggered electrically.
May be asking a lot of questions if we fully go through with it. How much did it cost. We would probably do something lower end. I’m thinking no tilt adjust and only one cannon. It’s funny that was the second time I watched the video haha I watched it first for inspiration.
Also what are the special parts you actually had to go out an buy like stuff most people don’t have laying around.
+1. A pneumatic explosion is not something you want to have to deal with. At the worst, somebody could be injured or killed, and at the least, your program could face very serious review or be shut down. This stuff is too serious to be decided by whether sprinkler valves and PVC are cheaper than legitimate pneumatic components.
I would recommend copper or brass piping for any pneumatic operations dealing with such large volumes of air due to the fact that it is actually rated for air pressure and less likely to shatter if it does fail.
The one we built was in the neighborhood of $5000 just for parts. But we started from scratch. The custom sheet metal chassis, paint job, and specialty designed adapter block to go from the solenoid to the barrel was donated, everything else we bought.
We are using twin scuba tanks. The pneumatic system was designed by a colleague who is a PE in piping design. We have several safety rated devices (Burst discs) in the lines so that we don’t over pressurize the system.
It isn’t a myth though. PVC isn’t rated for air pressure and when it fails it does so spectacularly. It will work fine for a while, you just won’t know when that while will end. And when that time comes, the result will at the least let blood come out of someone. The worst case scenario is much, much worse.
In order to get much range at low pressure, you’ll need to have large pipes and valves. On our air cannon, we use a 3/4" solenoid as the smallest point in the line. This means that we cannot use a tank designed for tools; the flow is not enough. We have a large (probably 8 gal) cast iron accumulator with about a 2" fitting at one end. We usually charge to about 40-50 psi, and have thrown t-shirts over the top of our press box with it at 60. Also, a large-bore relatively short barrel gets more of the energy to the shirt than long and narrow. We’re currently using a 3" barrel about 20" long. The 3" barrel also works well with small foam rubber footballs.
We figured out a very simple way to prepare the shirts for the launcher that does not require any tie wraps or string or tape:
Lay the shirt flat on a horizontal surface
Lift the bottom hem a few inches, and raise (relative to the shirt orientation) until the fold is at the armpit.
Lower the hem until the next fold is at the shoulder
Repeat the two previous steps until you’re out of shirt
Fold one sleeve over the shirt body
Roll from that sleeve, across to the other shoulder
flip the other sleeve inside out and wrap around the cylinder, like folding socks.
This fits a large short-sleeve shirt in our 3" barrel nicely. A small shirt may require making the cylinder a little shorter, and an XL a little longer.
Copper pipe is good.
Conduit may or may not be good. If it is plastic (especially PVC), do not use it. If it’s metal conduit, that should work.
Copper 1/16" wall is enough for the ~60PSI shock that the barrel should see max.
The biggest thing with the valve is safety and leakage. Make sure the valve is GAS rated for the max pressure it will see. The gas rating is important because most other valves will leak as well as possibly burst.
The most important thing here is safety. Remember that this will be in the public eye. Any failure, especially one that results in unexpected release of pressurized air, is very bad.
If you cannot afford to ensure it is completely safe at all times then don’t build it. That being said, with some leftover KOP/FirstChoice parts you should be able to build a decent safe single shooter for a few hundred dollars.