Proof Of Concept Valveless Air Canon

For the longest time I have been intrigued with canons of all sorts. Actually to boil it down I love loud explosive anythings. The louder the better. If it goes boom and you feel it in your chest I fall in love. Because of this fascination and the relative inexpensive of PVC I have invested my time in developing an air release for pneumatic devices that is essentially valveless. You won't have to fork out the extra cash for a butterfly valve or attempt to modify a sprinkler valve. While this proof of concept will reduce cost in your pneumatic devices it does have it's draw backs. I will explain throughout this ible. As this is my first ible please bear with me if I make a few mistakes.

For this ible I will be making a small scale model. There is a 3in by roughly 18in air reservoir which transitions down to a 1in by roughly 24in barrel. * I apologize for the gee by guesses, I actually made this PoC a few months ago and put it into storage when I moved. I am actually looking at pictures that I took while making it to write this. *

By reading this ible, you the reader, assume any and all responsibility in your attempts to recreate or modify this design.

Step 1 Parts Needed

Since were dealing with PVC aside from the obvious items needed (PVC Cleaner/Primer, PVC Glue, Safety Precautions) you will need the following:

18in x 3in PVC Pipe
3in PVC Cap
3in PVC Coupler
3in to 2in PVC Reducer
2in PVC Coupler
2in to in PVC Reducer
1in PVC Coupler (Despite the picture showing two)
1in PVC Cap (Despite the picture showing none)
24in x 1in PVC Pipe
1in O-Ring
Grease of any kind

Considering the price of a butterfly valve this is a relatively cost effective way to create a pneumatic device.

Comments

[admin]

This is a great Instructable, but you need to add a main image of the final project to the intro step. Please do that and leave me a message when you have so that we can publish your work. Thanks!

[Ian01]

When pressure testing, fill the device with water before fully pressurizing it. That way you'll be able to see the location of the leak. If it breaks it won't have enough energy to do any damage (because water is incompressible). You'll just end up with a wet floor, not shrapnel embedded in your body.

[joe korany]

actually here http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=66234

[aaon]

Ha, this is 9.99 + Shipping and handling. This is a POC for a valveless air cannon. Besides if your building these in bulk, butterfly valves get expensive. And in my neck of the woods you can tack another 5 or so bucks to each valve. It gets pricey.

[drhoff]

 POC stands for proof of concept?

[carl87gt]

Just found this one here. I LOVE all things PVC. Your release valve is brilliant, exactly what I was looking for. I think with a t-handle in the barrel I could make it easier to pull back under pressure. Either way it gives me a new direction to consider when designing release valve. Very nice.

[iloveairsoftstuff]

very nice. i am going to try to scale this down and build it out of pens.

[tjk94]

if you drill some holes around the base of the barrel you could have a one shot nail gun. Just push against your wall, floor, etc and boom! nail.

[aaon]

Could make a bolt action barrel for the nail gun too. Just get a piece of PVC to fit snuggly over the barrel. and then make a hole in the barrel just large enough to put the nail in.

[jomodad]

I'm sorry. I am new to air cannons and this site. How do you load this? Put the projectile down the barrel from the firing end?

[aaon]

Correct.

[joe korany]

just buy a metal ball valve with a switch on it for like 5 dollars

[clemsonguy1125]

what grease did you use and what sizt drill bit i am making mini with a one half barrel

[aaon]

For the grease, to be honest I didn't have any so I asked my neighbors. I believe it was just a generic lithium grease. Anything should work. You just want something that will help make a seal. And the drill bit I could have sworn it was 3/8. I don't have the internet at my house and only use the internet when I'm at my parents. Unfortunately I am at their house and I don't have the cannon with me to confirm.

[clemsonguy1125]

i built it and it works great i used petrolium jelly

[clemsonguy1125]

(removed by author or community request)

[aaon]

Thanks. Have fun and be careful.