Just got $200. Time to make a GB Cannon.

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
SpoonZ
Private 4
Private 4
Posts: 64
Joined: Thu May 10, 2007 1:15 am

Wed Jul 04, 2007 8:12 am

Seeing as I have $200. From selling one of my old hobbies. World Of Warcraft.

Now. I want to build a GB cannon.

What I want to know. If anyone know a online distributer for Aussie pipe?

And, what are the mauler valves like from BCarms.com. I will purchase one of those for the valves.

Going to do some drawings tomorrow.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Wed Jul 04, 2007 5:13 pm

So you have $171US. A mauler will cost you $90US
Then you have to pay shipping which will be a bit as mauler's I would expect to be around a 1.5-2kgs. So thats probably $25US right there.
So that leaves you with about $55US to buy a pilot valve, fill valve etc. Then you still need to buy pipe for your chamber and barrel and Aussie isn't the cheapest country to get it from.(NZ is worse)
Then you still need the basics primer, glue, gauge, fittings etc.

Just make your own valve, im not trying to stop you from buying from BCarms but if you want to have money to make a cannon I would make your own valve, not exactly hard.
This is my golfball cannon I just made with a homemade piston valve:
http://www.spudfiles.com/forums/viewtop ... tml#100616
SpoonZ
Private 4
Private 4
Posts: 64
Joined: Thu May 10, 2007 1:15 am

Thu Jul 05, 2007 1:28 am

200 US, 225 AUD. 227 to be exact. I have glue, and pilot valves. Filling valves. and some left over fittings. All I need is Chamber, barrel, mauler. Done. maybe a couple of snazzy fittings to make it cool.

Seems he doesnt make/sell them anymore. Will probably make a piston like yours. I just couldnt find anything that was a perfect round fit other then a 40mm coupler. Now. I just need a lynx can.
Last edited by SpoonZ on Thu Jul 05, 2007 1:47 am, edited 1 time in total.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Thu Jul 05, 2007 1:40 am

$200AUD = $171USD.

Ok well then go for it. Just make sure you dont order the pipe in 6m lengths at like $300. Most palces do that.
SpoonZ
Private 4
Private 4
Posts: 64
Joined: Thu May 10, 2007 1:15 am

Thu Jul 05, 2007 2:01 am

Hahah. Ouch. But what I couldnt figure out is how to make the piston servicible if you are going to have a bit of 50mm pipe inside to put an endcap on, then somewhat more from the barrel being slightly of the Down pipe over the T section. Wont that give the piston like, 1 or so inches to move? Then again. How are you going to get it out of the actual T.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Thu Jul 05, 2007 2:12 am

Well I did mine like this:
Image

And you only need the piston to move back a 1/4 of the barrels diameter.
SpoonZ
Private 4
Private 4
Posts: 64
Joined: Thu May 10, 2007 1:15 am

Thu Jul 05, 2007 2:23 am

Yeah, But. The end part with the screws. Is your piston fitting inside 50mm piping or the 50mm T. The T's diameter is different to the actual pipe that goes inside.

So what im trying to figure out, is how you are going to get the piston out of the T once 50mm pipe is placed in.

Nice gun aswell. Going to build something similar just different designs. Did you uses 50mm with another piece of 50mm sleeved inside for the barrel? diameter of golf ball is like 42mm. So 40mm wont work?.

Thanks.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Thu Jul 05, 2007 2:32 am

Yeah 40mm is nominal size not ID.. So 40mm PN18 PVC has an Inside Diameter of like 44mm.

The tee is sleeved with 50mm pipe. What you mean you can't get the piston out? You just pull it out. Its very hard to make a piston without sleeving the tee because of the lip found in most tee's.

Here's a quick diagram:

Image
SpoonZ
Private 4
Private 4
Posts: 64
Joined: Thu May 10, 2007 1:15 am

Thu Jul 05, 2007 2:51 am

Fair enough, so you just grind down the stops inside the T. slip in some 50mm both ends and go from there? So pretty much, the inside of your T is around 50mm in diameter instead of nearlly 60?

Thanks for the help.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Thu Jul 05, 2007 2:57 am

No....

Ok, in one end of the 50mm tee you get a 50mm bushing for your barrel.
Then in the other end, the pilot end you stick in 50mm pipe until it hits the stop. Now the whole tee has an I.D of 50mm. Stick out about 5cm of 50mm pipe to bolt an end cap on.
SpoonZ
Private 4
Private 4
Posts: 64
Joined: Thu May 10, 2007 1:15 am

Thu Jul 05, 2007 3:01 am

We dont have great bushings here. Its exactly what I meant. Just no stops. hah.

I have to slip in 50mm pipe into the barrel end then a coupler on top then Bushings. our bushins are shit. Thanks for the help mate.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Thu Jul 05, 2007 3:08 am

Why are your bushing crap? Don't use a reducer.

Just go to a plumbing merchants and get one, theyre cheaper as well.
SpoonZ
Private 4
Private 4
Posts: 64
Joined: Thu May 10, 2007 1:15 am

Thu Jul 05, 2007 3:21 am

True, the plumbing store is right next to bunnings. But I dont know. Ive been to others before. and they only they dont have them, only the couplers then reducers. so, coupler, reducer etc etc. But Ill check em out.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Thu Jul 05, 2007 3:36 am

Reducers aren't pressure rated.
Just ask for a bushing see if they have them.
SpoonZ
Private 4
Private 4
Posts: 64
Joined: Thu May 10, 2007 1:15 am

Thu Jul 05, 2007 3:41 am

Ah well then there not reducers, I only use pressure rated stuff.
Post Reply