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Re: Small caliber spud gun/ Nerf gun

Posted: Sun May 15, 2011 4:56 am
by Stormling
jackssmirkingrevenge wrote:
Stormling wrote:I'll actually use it but I sorta need the trigger not inline with the tank so I can mount it, thats why I was going with the modified valve.
A diagram of your intended configuration would help us help you ;)
So I'm correct in thinking that if I get a blowgun with a good flow, i pump up the tank stick in the dart and pull the trigger I can fire.
Pretty much.
I think a blowgun triggered QEV would be a good choice
Most people don't realise that with a decent barrel blowguns used directly make pretty good valves. I did this with this:

Image

Add a properly set detent and it has the potential to be more powerful than any piston valve.
I have definitely found the type of valve I need thanks or the help.

Posted: Sun May 15, 2011 4:57 am
by Stormling
I'll see if a can post up some diagrams of my original design as well.

Posted: Mon May 16, 2011 1:59 am
by Stormling
Btw if you could give me some info about the valve in that pic that would be great.

Posted: Mon May 16, 2011 4:23 am
by jackssmirkingrevenge
Stormling wrote:Btw if you could give me some info about the valve in that pic that would be great.
It's just a common blowgun valve, you can get a similar one for peanuts off eBay.

Posted: Mon May 16, 2011 4:39 am
by Stormling
Thanks for the help.
Do a need a barrel that big though.

Posted: Mon May 16, 2011 4:48 am
by Labtecpower
Stormling wrote:Thanks for the help.
Do a need a barrel that big though.
depends on when you're satisfied. more barrel = more power (to a certain degree)

Posted: Mon May 16, 2011 4:50 am
by Stormling
Labtecpower wrote:
Stormling wrote:Thanks for the help.
Do a need a barrel that big though.
depends on when you're satisfied. more barrel = more power (to a certain degree)
So I can just keep cutting of bits till Ii'm at a happy medium with length and power?

Posted: Mon May 16, 2011 4:55 am
by Labtecpower
yes. but you lose power with every bit you cut off.

have a play with this if you want to see figures.

Posted: Mon May 16, 2011 5:00 am
by Crna Legija
yea but then if you lop off to much you need to buy a new one. you should use GGDT read the instruction on the sit on how to use it and if your using vista run as admin or it wont work.

set the valve to generic, seat dia about 0.5 cm, opening time 15ms and dwell about the same(guessing but should be around that), then play with pressure and barrel length

edit ahh to slow

Posted: Mon May 16, 2011 5:06 am
by Stormling
Crna Legija wrote:yea but then if you lop off to much you need to buy a new one. you should use GGDT read the instruction on the sit on how to use it and if your using vista run as admin or it wont work.

set the valve to generic, seat dia about 0.5 cm, opening time 15ms and dwell about the same(guessing but should be around that), then play with pressure and barrel length

edit ahh to slow
10 ms then

Posted: Mon May 16, 2011 5:16 am
by Crna Legija
Stormling wrote:
Crna Legija wrote:yea but then if you lop off to much you need to buy a new one. you should use GGDT read the instruction on the sit on how to use it and if your using vista run as admin or it wont work.

set the valve to generic, seat dia about 0.5 cm, opening time 15ms and dwell about the same(guessing but should be around that), then play with pressure and barrel length

edit ahh to slow
10 ms then
no i was to slow to get u the info not teh valve

Posted: Mon May 16, 2011 5:22 am
by Stormling
No not really you gave me an excellent springboard.

Posted: Mon May 16, 2011 5:26 am
by Labtecpower
you was too slow to give the GGDT info, but I didn't give valve info. I recommend a seat dia of about 0,2 cm. There are a lot of twists, turns & holes in the blowgun guts.

Posted: Mon May 16, 2011 5:57 am
by Stormling
So i'm still gonna need some designs/help with a tank.
I'm now going for a 75-100 psi tank on recommendations from Jackssmirkingrevenge. I'm only getting messages saying that the projectile has not left the muzzle so i'm hoping with more experimentation with the program I can get success.

Posted: Mon May 16, 2011 6:01 am
by Crna Legija
get a screen shot of ggdt for us to see.