SpudFiles

Heyy
I'm am looking at building this....
But there are a few things im not sure about....

Im the first to say im a "newb".
I have already made a spud gun powered by hairspray.
Works fine, but it just isnt enough i want to build something more bigger and better and put alot more effort into it and do a paint job ect. If you need any information just ask, if anyone could help me with size's ect it would be great i look forward to posting damage reports and photo's on here.

The cannon below is a propane one just incase you could'nt notice.
The "White" part is the chamber. I have enough money to build it all.
The problem is im not sure how much Propane to put in it (safe amount)
Ill be using ABS pipe im pretty sure i just want it to me a safe good looking cannon to have some fun with.
Other than that can you see any other problems?
Sorry for the bad picture (the silver part on the right is a 9V fan.
<a href="http://www.picoodle.com/view.php?img=/4 ... &srv=img34" target="_blank"><img src="http://img34.picoodle.com/img/img34/4/6 ... 72c3d5.png" border="0" alt="Image Hosting by Picoodle.com"></a>

The problem is im not sure how much Propane to put in it (safe amount)

I'll let some combustion Guru's answer your questions, but i'll just tell you this one thing.

There is no 'safe' amount of propane to use. Only an amount that will ignite. If the mixture is too rich or to weak, it wont ignite. If it's perfect, the mixture will ignite.

There are quite a few threads detailing how to make a propane meter and work out the correct amount of propane needed for your cannon.

Okay thank you
Ill keep that in mind
im just getting some info from the pro's
before i spend quite alot of money.

You'll need a fuel meter designed for your chamber volume. I recommend you go to Latke's website and read through the entire site, several times if necessary. It is the defacto standard information on advanced combustion design. It discusses how to calculate your fuel requirements.

Latke is a great site. If need be download HGDT (?) and work out your dimensions. Other than that look around. Its a full site and theres loads of information here for you to use. Enjoy