Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 69 users online :: 6 registered, 0 hidden and 63 guests


Most users ever online was 218 on Wed Dec 07, 2016 6:58 pm

Registered users: Bing [Bot], Exabot [Bot], Google [Bot], Google Adsense [Bot], MSNbot Media, Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

Need someone more expierenced please

A place to ask general spud cannon related questions.
Sponsored 
  • Author
    Message

Need someone more expierenced please

Unread postAuthor: grum7n7 » Mon Jul 24, 2006 8:17 pm

I am making my first propane gun...i made some rough plans for it...i know the chamber size and barrel length and the amount of propane but i dont know the meter pipe length yet because i need to figure out a pressure to run it at...

barrel = 40" x .5"
combustion = 8" x 1'
amount of propane in chamber = 4.12ml

questions

1) will this plan work? if not please give me some corrections or tips
2) will the bend going from the combustion to the barrel affect anything as opposed to it being just straight?
3)same for the propane steup? will the propane setup work?
4) what pressure should i run this at (at 90 psi the meter pipe would have to be .24 inches long lol)
5)please tell me anything you see wrong with and a solution

im not being demanding and i dont mean to sound it, but im somewhat of a noob when it comes to propane stuff...if you dont want to help me dont, but if you wish, help me please...it will be appreciated

thanks

nick
  • 0

Attachments
sniper plan.JPG
the plan

grum7n7
Private
Private
 
Posts: 14
Joined: Tue Jul 18, 2006 6:49 pm
Location: Vermont
Reputation: 0

Unread postAuthor: Mihlrad » Mon Jul 24, 2006 8:25 pm

http://burntlatke.com/ft_live.html

Use that to calculate the sizes.
  • 0

User avatar
Mihlrad
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 467
Joined: Tue May 23, 2006 6:45 pm
Reputation: 0

Unread postAuthor: grum7n7 » Mon Jul 24, 2006 8:35 pm

if the pressure is at 21.5 psi with a 3/8 meter pipe it will give me a length of 1 inch...

will a 1 inch meter pipe be ok and will 21.5 psi be enough pressure to empty all the propane into the chamber?
  • 0


grum7n7
Private
Private
 
Posts: 14
Joined: Tue Jul 18, 2006 6:49 pm
Location: Vermont
Reputation: 0

Unread postAuthor: Mihlrad » Mon Jul 24, 2006 8:54 pm

if the fuel tool says its ok, its ok... but 1 inch at 21.5 psi seems a bit low, how small was the chamber again?
  • 0

User avatar
Mihlrad
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 467
Joined: Tue May 23, 2006 6:45 pm
Reputation: 0

Unread postAuthor: SpudStuff » Mon Jul 24, 2006 8:55 pm

that won't be very powerful
  • 0

User avatar
SpudStuff
Major General
Major General
 
Posts: 1410
Joined: Sat Dec 10, 2005 3:55 pm
Location: Cupertino, California
Reputation: 1

Unread postAuthor: grum7n7 » Mon Jul 24, 2006 9:00 pm

yeah tahts what i was thinking that it wouldnt be very powerful...


the chamber volume is 6.28 cu. in....102.91ml

should it be bigger and mae the barrel bigger too to keep the .8:1 ratio
  • 0


grum7n7
Private
Private
 
Posts: 14
Joined: Tue Jul 18, 2006 6:49 pm
Location: Vermont
Reputation: 0

Unread postAuthor: SpudStuff » Mon Jul 24, 2006 9:20 pm

um that would be like a mini.

look into using a pnumatic. the only modification to your current design is to add a valve to the barrel near the rear. it will be much more powerful
  • 0

User avatar
SpudStuff
Major General
Major General
 
Posts: 1410
Joined: Sat Dec 10, 2005 3:55 pm
Location: Cupertino, California
Reputation: 1

Sponsored

Sponsor
 


Unread postAuthor: Mihlrad » Mon Jul 24, 2006 10:22 pm

If your going to use propane just use 4" or 3" pipe, it will cost you 3x as much though, i agree with spudstuff go pnuematic, same design with a valve in it. Far cheaper too.
  • 0

User avatar
Mihlrad
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 467
Joined: Tue May 23, 2006 6:45 pm
Reputation: 0

Unread postAuthor: grum7n7 » Tue Jul 25, 2006 1:28 pm

aright ill go pnuematic then...should i keep the same ratio (.8:1) or is the ratio supposed to be different???

also the bend from the chamber to the barrel has no effect right??
  • 0


grum7n7
Private
Private
 
Posts: 14
Joined: Tue Jul 18, 2006 6:49 pm
Location: Vermont
Reputation: 0

Unread postAuthor: SpudStuff » Tue Jul 25, 2006 2:34 pm

the bend will have an effect because air is a fluid and fluids loose speed each time they change direction. you couuld ude to make the chamber larger. tre 2" x 8" and for the barrel use 3/4 inch CPVC so you can shoot paint balls. when you install your valve put it between thebarrel and the bends at the rear. i would recoment using a modified sprinkler valve.
  • 0

User avatar
SpudStuff
Major General
Major General
 
Posts: 1410
Joined: Sat Dec 10, 2005 3:55 pm
Location: Cupertino, California
Reputation: 1

Unread postAuthor: Shrimphead » Tue Jul 25, 2006 2:40 pm

The bend will have an effect, but it is pretty minimal. Over-unders are probably one of if not the most common pneumatic, so don't worry about it.
  • 0

Controlled insanity = Genius
Life flies when you're being dumb.
User avatar
Shrimphead
Colonel
Colonel
 
Posts: 509
Joined: Thu Nov 17, 2005 7:42 pm
Reputation: 0

Unread postAuthor: grum7n7 » Tue Jul 25, 2006 3:21 pm

aright cool guys

thanks
  • 0


grum7n7
Private
Private
 
Posts: 14
Joined: Tue Jul 18, 2006 6:49 pm
Location: Vermont
Reputation: 0

Unread postAuthor: grum7n7 » Tue Jul 25, 2006 3:21 pm

what pressure would you run it at?

and how does it compare to a combustion
  • 0


grum7n7
Private
Private
 
Posts: 14
Joined: Tue Jul 18, 2006 6:49 pm
Location: Vermont
Reputation: 0

Return to General Spud Cannon Related

Who is online

Registered users: Bing [Bot], Exabot [Bot], Google [Bot], Google Adsense [Bot], MSNbot Media, Yahoo [Bot]

Reputation System ©'