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 52 users online :: 4 registered, 0 hidden and 48 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

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

The Team
Administrators
Global Moderators
global_moderators.png CS

Solenoid for GB gun?

Post questions and info about pneumatic (compressed gas) powered cannons here. This includes discussion about valves, pipe types, compressors, alternate gas setups, and anything else relevant.
Sponsored 
  • Author
    Message

Solenoid for GB gun?

Unread postAuthor: Carlman » Wed Feb 20, 2008 11:36 am

Hi all,

back in the day when i was just starting out in spudguns i built a 9' long ball valve GB gun. Now as you can probobly imagine the power was not that great because of the 2" pvc ball valve :D

so..it leads me to this, go fork out 70$ for a 2" sprinkler valve (of which i need ideas for a pilot, preferably a manually operated one) or go with a 1" sprinkler valve.

Would i get decent power with this as 100 psi with the latter? Or would the flow of the 2" blow it out of the water?

Image

the pipe for the chamber is rated to 18 bar and so is all of the fittings including the 2" to 1.5" reducing bell.

I know there is massive primer stains and even glue stains on it, but it was my first pvc welding job so bear with me.

Before you go telling me to make a piston, my resoning is i want to keep it as an inline and also i wish to make a smalller PV before i attemp at 2" porting one. I also do not wish to purchase of the net so no maulers or supahs for me.
  • 0

Image
Aussie spudders unite!!
User avatar
Carlman
Major General
Major General
 
Posts: 1618
Joined: Sat Nov 24, 2007 1:18 am
Location: Western Australia
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Wed Feb 20, 2008 11:54 am

Remember that area and therefore flow increases exponentially with diameter, therefore a 2" port has 4 times the flow of a 1" port, food for thought ;)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Carlman » Wed Feb 20, 2008 12:16 pm

yea forgot bout that JSR, who would know what to pump into GGDT for a 2" sprinkler valve?

Should get some decent power aye :D
  • 0

Image
Aussie spudders unite!!
User avatar
Carlman
Major General
Major General
 
Posts: 1618
Joined: Sat Nov 24, 2007 1:18 am
Location: Western Australia
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Wed Feb 20, 2008 12:21 pm

Carlman wrote:Should get some decent power aye :D


Well if this is anything to go by :D
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: dewey-1 » Wed Feb 20, 2008 12:40 pm

--
  • 0

Last edited by dewey-1 on Sun Apr 20, 2008 1:14 pm, edited 2 times in total.
User avatar
dewey-1
Major General
Major General
 
Posts: 1298
Joined: Wed Mar 28, 2007 10:24 am
Location: NE Wisconsin USA
Reputation: 0

Unread postAuthor: SpudFarm » Wed Feb 20, 2008 12:57 pm

if you want it inline go ahead and make a coaxial;)

or if you has something against pistons do as dewey said but i would go with coaxial since it is an easy build and will give you more power :)
  • 0

User avatar
SpudFarm
Donating Member
Donating Member
 
Posts: 2563
Joined: Sat Nov 04, 2006 9:39 am
Location: Norway Trondheim area
Reputation: 0

Unread postAuthor: MrCrowley » Wed Feb 20, 2008 1:27 pm

I still get decent power with the <A HREF="http://www.spudfiles.com/forums/viewtopic,p,136108.html#136108">SG-V</a>. Have never measured the distance but looks like it shoots around 200 meters.
  • 0

User avatar
MrCrowley
Moderator
Moderator
 
Posts: 10207
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Country: New Zealand (nz)
Reputation: 4

Sponsored

Sponsor
 


Unread postAuthor: dongfang » Wed Feb 20, 2008 4:21 pm

Hi

JSR, one little thing:

Remember that area and therefore flow increases exponentially with diameter


Naaah not quite. Area grows by the square of the diameter. Exponential growth is faster.

Example:

[n, 100 * n^2, 2^n]:
[0, 0, 1]
[1, 100, 2]
[2, 400, 4]
[3, 900, 8]
[4, 1600, 16]
[5, 2500, 32]
[6, 3600, 64]
[7, 4900, 128]
[8, 6400, 256]
[9, 8100, 512]
[10, 10000, 1024]
[11, 12100, 2048]
[12, 14400, 4096]
[13, 16900, 8192]
[14, 20400, 16384]
[15, 22500, 32768]
[16, 25600, 65536]

(the exponential function eventually outgrows the quadratic one, even if multiplying that by 100 .. (or any other number))

OK never mind....

(ever thought of why the standard sizes of fittings are about what they are? For each bigger size, the area grows by about the square root of 2. Going up 2 sizes doubles the area).

Carlman I'm afraid you can't get a golf ball into a 40 mm pipe. The ball is 42.67 or something like that. But build the gun anyway; 40mm is a good size, not too big (expensive, lots of pumping etc) and not too small (boring).

I have shot golf balls with an 1" sprikler and a 50mm barrel. It worked ok but it could have been better. Anyway shooting almost vertically the GBs got so high up that they were really hard to find again. I think an 1" sprinkler could perform very well with a 40mm pipe (its ID would be 35mm or so). You could try with an 1" first and then maybe try building a piston valve. The metric parts are wonderful for using end caps as pistons...

Regards
Soren
  • 0

User avatar
dongfang
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 448
Joined: Sun Aug 27, 2006 8:02 am
Location: Switzerland
Reputation: 0

Unread postAuthor: Carlman » Wed Feb 20, 2008 6:39 pm

@dewey-1: Thanks for your input, like the Shock and Awe my valve comes to a point that would suit a 3/8" ball valve perfectly. The picture you posted looks like the pilot flow is constricted to 3/8" anyway so flinging open an easy ball valve shouldn't give that much of a performance drop.

spudfarm wrote:if you want it inline go ahead and make a coaxial;)

or if you has something against pistons do as dewey said but i would go with coaxial since it is an easy build and will give you more power :)


The point of getting this valve is to use the pipe i all ready had. The chamber is really thick and the barrel only just slides inside it, so no coaxial for this one .

MrCrowley wrote:I still get decent power with the <A HREF="http://www.spudfiles.com/forums/viewtopic,p,136108.html#136108">SG-V</a>. Have never measured the distance but looks like it shoots around 200 meters.


I have seen your cannon before, at say 100 psi what thickness ply could it go through? The 1" seemed to have worked for you there but all i wonder is going with the 2" going to make a big difference.

dongfang wrote:Carlman I'm afraid you can't get a golf ball into a 40 mm pipe. The ball is 42.67 or something like that. But build the gun anyway; 40mm is a good size, not too big (expensive, lots of pumping etc) and not too small (boring).


I'm afraid i can get a golfball in 40mm cpvc pipe :wink:

It fits so well that if you block off one end of the barrel it will take approx 2 seconds to get to the other end!
  • 0

Image
Aussie spudders unite!!
User avatar
Carlman
Major General
Major General
 
Posts: 1618
Joined: Sat Nov 24, 2007 1:18 am
Location: Western Australia
Reputation: 0

Unread postAuthor: bigbob12345 » Wed Feb 20, 2008 8:08 pm

Yes the 2in sprinkler will make a very large difference over a 1in one I would recomend you make a piston valve but you are not willing to do that. A 1.5in sprinkler will work fine and wouldnt get much less power than a 2in sprikler.
I guess you could also use a 1.25in sprikler but you wouldnt get as much power.
A 1in sprinkler on that size chamber would constrict flow tremendously.
  • 0

User avatar
bigbob12345
Major General
Major General
 
Posts: 1516
Joined: Sat Dec 01, 2007 9:13 am
Location: Mercer Island,Washington
Reputation: 0

Unread postAuthor: Carlman » Wed Feb 20, 2008 8:32 pm

yea i know there will be a large diference, it will actually cost more to have a 1.5" rather than a 2" because of pvc fittings i would need to bring it back down to size.
  • 0

Image
Aussie spudders unite!!
User avatar
Carlman
Major General
Major General
 
Posts: 1618
Joined: Sat Nov 24, 2007 1:18 am
Location: Western Australia
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Wed Feb 20, 2008 10:35 pm

dongfang wrote:Naaah not quite. Area grows by the square of the diameter. Exponential growth is faster.


Right you are, my bad :oops:
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: MrCrowley » Wed Feb 20, 2008 10:38 pm

dongfang wrote:
Carlman I'm afraid you can't get a golf ball into a 40 mm pipe. The ball is 42.67 or something like that. But build the gun anyway; 40mm is a good size, not too big (expensive, lots of pumping etc) and not too small (boring).


40mm PVC Pressure Rated pipe has an I.D of about 43.5mm. You're referring to the nominal diameter, which in some countries(UK I think) is the real I.D so I think that's where you are confused.


@Carlman

No idea, never used it for damage shots, except for the watermelon, after it blew the wastermelon up, it stopped dead, didn't hit my back stop about a foot or two away.
  • 0

User avatar
MrCrowley
Moderator
Moderator
 
Posts: 10207
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Country: New Zealand (nz)
Reputation: 4

Unread postAuthor: dongfang » Mon Mar 03, 2008 11:37 am

Hi McCrowley,

OK, if the pipe is large enough then.......

In here, an X mm pipe is ... taddaaaaaaa --- X mm in the outside. No more no less.

Regards
Soren
  • 0

User avatar
dongfang
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 448
Joined: Sun Aug 27, 2006 8:02 am
Location: Switzerland
Reputation: 0

Unread postAuthor: Carlman » Mon Mar 03, 2008 11:44 am

good for you dongfang :D

no seriously what was the point of that?

different places have different ways of measuring pipe.
  • 0

Image
Aussie spudders unite!!
User avatar
Carlman
Major General
Major General
 
Posts: 1618
Joined: Sat Nov 24, 2007 1:18 am
Location: Western Australia
Reputation: 0

Next

Return to Pneumatic Cannon Discussion

Who is online

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

Reputation System ©'