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1st Attempt On Pneumatic
Posted: Wed Dec 24, 2008 4:48 am
by littlebro05
Hey guys,
I'm usually trying to make BBMG's and airsoft related things since Australia bans those kind of things and I think I've got bored of it for a while. Anyway the point being is that I want to attempt at my first pneumatic... and I'm going the old style ball valve since it's probably the most easiest and cheapest thing for me to make.
Anyway I've reading spudwiki and I'm planning to have a C:B ratio of 2250ml:295ml and was wondering is that more than enough? I'm not really good at maths but should I use 1250ml:295ml or 2250ml:295ml. Would having too big of an air tank affect it's velocity?
Anyway these are my plans after Christmas when shops are opened.
Sorry that I don't really understand it... it's my first attempt at it.
P.S. Barrel Diametre is 25mm and Barrel Length is 600mm.
Posted: Wed Dec 24, 2008 5:31 am
by Cosmic Muffin
mate if its your first shot at it, bugger the ratio and just try it out
if you have a 1.25l coke bottle, just stick a ball valve to the end and to that screw in a piece of retic pipe.
Posted: Wed Dec 24, 2008 5:36 am
by jackssmirkingrevenge
Get a sprinkler valve, a bit more expensive (but you should have plenty of xmas $$$ from aunties etc

) but worth the increase in performance.
Posted: Wed Dec 24, 2008 5:47 am
by Carlman
and with those extra dollars get some PVC for the chamber

Posted: Wed Dec 24, 2008 5:49 am
by littlebro05
jackssmirkingrevenge wrote:Get a sprinkler valve, a bit more expensive (but you should have plenty of xmas $$$ from aunties etc

) but worth the increase in performance.
Haha... well actually I don't have the time to make some fancy pants sprinkler valve... and I haven't found any around... I'm just doing this for it's simplicity of making it in like an hour then waiting a day for the epoxy to harden. Haha yes, xmas... + I'm asian I get chinese new year's money too XD.
Well yeah, I think i'm just going to use the bigger one because I think it might give me the bigger shot. I'll work on the sprinkler valve once I've leave high school and have time to work on it... next year is my final years XD so yeah. Thanks for the reply.
Edit: Lol, I'll work on the sturdiness once I've left high school since I don't have the time to go out and buy PVC chamber... my local hardware store only sells PVC DWV so that's why I'm using a bottle. I might go out and try some pressure rated pipe, but not now

.
Posted: Wed Dec 24, 2008 6:05 am
by Cosmic Muffin
well try bunnings cos they stock pressure rated parts.
and if you want to try make a pneumatic, you should "got the whole 9 yards" and make something decent, you will want to upgrade at some stage anyway. final yr of school.. would that be yr 12?
im goin into yr12 nxt yr.
im bloody scared of the TEE

Posted: Wed Dec 24, 2008 6:31 am
by Pyro Ninja
littlebro05 wrote:jackssmirkingrevenge wrote:Get a sprinkler valve, a bit more expensive (but you should have plenty of xmas $$$ from aunties etc

) but worth the increase in performance.
Haha... well actually I don't have the time to make some fancy pants sprinkler valve... and I haven't found any around...
Go to bunnings and get a sprinkler valve for around $22, you won't regret it and It is extremely simply to mod (If you can drill a hole and bend a small rod then you'll be fine)
If you need any help just ask.
Posted: Wed Dec 24, 2008 6:41 am
by Cosmic Muffin
what do you mean bend a small rod?
the guide rod?
cos i thought you either take it our or leave it in, when would you need to bend it.
Posted: Wed Dec 24, 2008 6:59 am
by ALIHISGREAT
its definitely worth scrapping your design and drawing up something safer and more advance.
so as has already been mentioned, a Sprinkler valve is a good way to start... and a PVC chamber would be safer too...
i however recommend for a first, a QEV, they offer the simplest option because you can use all off the shelf threaded parts, making construction easy, and QEVs outperform Sprinkler valves without the need for a mod.
Posted: Wed Dec 24, 2008 7:03 am
by Cosmic Muffin
yer but we find it hard to get QEVs here in Australia.
most people i talk to on this forum have to order them off the net.
I'm just doing this for it's simplicity of making it in like an hour .
it doesnt seem like he wants to spend too much time or money on it

Posted: Wed Dec 24, 2008 7:47 am
by Pyro Ninja
Cosmic Muffin wrote:what do you mean bend a small rod?
the guide rod?
cos i thought you either take it our or leave it in, when would you need to bend it.
Yes, the guide rod, with the bunnings sprinkler valves you keep the rod in, all you have to do is bend it so it stays in the right spot (its original placement is in the way of where you need to drill)
Posted: Wed Dec 24, 2008 7:57 am
by littlebro05
Well... I could attempt the sprinkler valve but I don't have access to any bunnings

so it's abit hard for me to get the sprinkler valve... but if I do go to bunning I will buy it and have it in the corner of my room until I graduate, yes from year 12, i'm friggin scared to man F up this thing you could be screwed for life lol.
But yeah I'll use a sprinkler valve at the end of next year if these forums are still alive lol... at the moment I want to make something quick to put together... + my parent's are prohibiting me from making anymore gun related constructs until I graduate.
"Stop getting distracted with your guns! Get studying!" - quote from ma and pa.
Posted: Wed Dec 24, 2008 8:02 am
by Pyro Ninja
Well, MERRY CHRISTMAS spudfiles

Posted: Wed Dec 24, 2008 10:02 am
by LCTChamp
You could always get the sprinkler valve off of ebay.
Posted: Thu Dec 25, 2008 2:38 pm
by SP00K
Check out the
blood squirter design, the link won't take you directly to it because my computers being funny. But all you have to do is type in blood squirter in the search bar. It sounds off topic, but it's design is relevant.