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 43 users online :: 4 registered, 0 hidden and 39 guests


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

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

Performance beyond my expectations!

Built a pneumatic cannon? Then post it here! This section is for completed, finished cannons that you have built. Please include pictures and information.
Sponsored 
  • Author
    Message

Performance beyond my expectations!

Unread postAuthor: rejeanboucher » Sun Mar 11, 2007 12:42 am

- Solid IPEX schedule 40 ABS pipe. wrapped with fiberglass tape
- 2 inch x 36 inch barrel
- 3 inch x 32 inch pressure chamber, 2 to 1 volume ratio
- 3/4 modified valve (partition was removed within the cavity on the exit side, anti-siphon valve was fixed)
- at 80 PSI the spuds are knocked out at well over a thousand feet and will go clean thru a 3/4 inch high density MDF furniture board from 30 feet.
[/img]
  • 0

Attachments
spudgun 003.jpg
spudgun 003.jpg (27.52 KiB) Viewed 912 times
spudgun 002.jpg

rejeanboucher
Private
Private
 
Posts: 2
Joined: Mon Feb 19, 2007 1:18 am
Reputation: 0

Unread postAuthor: shud_b_rite » Sun Mar 11, 2007 12:48 am

very impressive. very impressive indeed
  • 0

Airbeds... so many different uses
User avatar
shud_b_rite
1st Lieutenant
1st Lieutenant
 
Posts: 290
Joined: Tue Jan 30, 2007 7:10 pm
Location: Auckland, New Zealand
Reputation: 0

Unread postAuthor: MrCrowley » Sun Mar 11, 2007 12:50 am

Whats with the fibre glass tape? Im not sure if thats the rare pressure rated ABS pipe you have but I wouldnt use it on a pneumatic.
And are you sure you shot at MDF not chipboard? MDF is very very hard to break. I only just get through chipboard at 700fps with a fishing sinker.
Oh an im pretty sure that bell reducer isnt rated either.
Other then that nice gun.

Edit:Care to change that title of yours? The rules say otherwise if you think it gets attention. Well it does get attention but its illegal attention :wink: jk

General posting guidelines:
When creating any new topic or post, please refrain from the use of ALL CAPS. It's annoying
  • 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: sjog » Sun Mar 11, 2007 1:14 am

come on man 1000 ft?
don't bullship a bullshipper
  • 0


sjog
Donating Member
Donating Member
 
Posts: 440
Joined: Sun Oct 15, 2006 9:43 pm
Location: Marthas Vineyard
Reputation: 0

Unread postAuthor: Killjoy » Sun Mar 11, 2007 1:41 am

yeah that range seems only slightly exagerated.... other then that nice lookin cannon, the fiberglass tape is pretty cool, though if thats cellular core it won't provide any protection.
  • 0


Killjoy
Brigadier General
Brigadier General
 
Posts: 1053
Joined: Sun Nov 12, 2006 12:51 am
Location: New Mexico
Reputation: 0

Unread postAuthor: noname » Sun Mar 11, 2007 12:02 pm

I love how you were shooting at "high density MDF (medium density fiberboard) furniture board." :lol:
NEVER USE ABS IN PNEUMATICS! It WILL blow out eventually! It's not meant for pressure.
And over 300 yards with a crappy, lower than inline low flow sprinkler valves and a short barrel, you're good at judging distance.
  • 0

User avatar
noname
Lieutenant General
Lieutenant General
 
Posts: 2699
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA
Country: United States (us)
Reputation: 9

Unread postAuthor: squeaks » Sun Mar 11, 2007 12:10 pm

WARNING: DON'T USE ABS OR BELL REDUCERS!!!
You're going to kill yourself. Unless you got the extremely rare, pressure rated abs and even rarer, pressure rated abs bell reducers, than this cannon is going to blow apart in your face. Don't use it!
  • 0

"Nine out of ten Americans agree that out of ten Americans one will always disagree with the other nine."
-Collin Mockery
Who's Line is it Anyway

Borrow money from a pessimist, he won't expect it back.

squeaks
Captain
Captain
 
Posts: 326
Joined: Sun Oct 01, 2006 5:45 pm
Location: Enoch, UT(next to Cedar City)
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: SpudBlaster15 » Sun Mar 11, 2007 1:11 pm

Oh no! It is made of ABS!!! That means it HAS TO explode, because its not pressure rated!!

I guarantee that if the launcher is made of solid wall DWV ABS, and he keeps the pressure under 100psi, it is not going to explode. Just because the pipe isnt rated for pressure doesnt mean it cannot hold pressure. I have pressure tested the DWV ABS and DWV ABS fittings by filling a closed chamber to 115psi, and leaving it for 3 days. It didnt show any signs of failure at all.

Besides, if it does explode, it will tear in one area rather than shrapnelling. I have ignited a mixture of pure oxygen and propane inside a closed ABS chamber, and it did fail, but the pipe bulged outward, and tore lengthwise along a 2" track. It definatley wont kill you.

To those who state that ABS is not intended to be used in pressure applications... if this is true, why do they produce pressure rated pipe (the only plastic pressure pipe actually intended for use with pressurized gases actually) using the ABS polymer?

I am not suggesting it's use as a pneumatic construction material, but it certainly isnt as bad as most make it out to be.
  • 0

User avatar
SpudBlaster15
Major General
Major General
 
Posts: 2385
Joined: Wed Oct 18, 2006 11:12 pm
Location: Canada
Country: Poland (pl)
Reputation: 3

Unread postAuthor: noname » Sun Mar 11, 2007 2:31 pm

It's not the worst, but it's definitely not the best, and shouldn't be used for pneumatics. I know it tears intead of fragging, but it isn't safe and even having it tear, in public or anywhere else, can give spudguns a bad name, and they may be illegalized. That's probably ot going to happen, but remember Murphy's Law.
  • 0

User avatar
noname
Lieutenant General
Lieutenant General
 
Posts: 2699
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA
Country: United States (us)
Reputation: 9

Unread postAuthor: Matheusilla » Sun Mar 11, 2007 6:44 pm

I can't find pressure rated pvc at any of the hardware stores around here. If I wanna do anything I have to use steel. I don't know what to do for a pressure tank for a pneumatic :cry:

BTW, I have used dwv abs sch 40 under pressure but I don't like it. I've seen aged pieces of it and it isn't good. It gets really brittle and it's color fades; scary stuff.
  • 0


Matheusilla
Sergeant First Class
Sergeant First Class
 
Posts: 140
Joined: Tue Feb 13, 2007 7:43 pm
Reputation: 0

Unread postAuthor: Pete Zaria » Sun Mar 11, 2007 6:54 pm

Look up plumbing supply or sprinkler supply stores from the phone book. You can almost always find a good selection of pressure rated pipe there. If all else fails, call contractors and house-building companies and ask where they get their PVC. They have to use pressure rated stuff for water lines....

I've pressure tested ABS cell core DWV sch40 pipe and fittings upto 4" to 125psi (remotely) for testing and it didn't blow. When I forced it to fail (dry ice and water in a sealed chamber... a long ways away...), it ripped open cleanly, the long way (end-to-end), along a wall of the 4" pipe. No shrapnel or missing bits. It depressurized pretty cleanly. For these reasons, I think it's an excellent material for combustions. NSF-PW SCH40 or better PVC is the best choice for pneumatics... but I think as long as you take good care of that gun (never store it in direct sunlight, try to avoid dropping it, never fill it over about 80psi....) it should be fine. Don't sue me if I'm wrong, though.

I don't think the fiberglass tape will actually do much, btw.

Cool design. Looks nice and clean.

Sorry, I have to agree with the others, 1,000 yards is nearly impossible for a gun with a 3/4" valve at 80psi. If you fired it from the top of a mountain, at a 45 degree angle, with the wind behind you, you might get 1000. My best gun can get a little over 350 with the right projectile...

Peace,
Pete Zaria.
  • 0

User avatar
Pete Zaria
Moderator
Moderator
 
Posts: 978
Joined: Fri Mar 31, 2006 6:04 pm
Location: Near Seattle, WA
Reputation: 0

Unread postAuthor: schmanman » Sun Mar 11, 2007 6:54 pm

nice, is the barrel sch 80? I notice you have a separate spud cutter, why not just sharpen the end of your barrel?


I like it, though.

spudblaster, I think you've put the whole "abs will kill you" thing to death, and buried it in your back yard!

bows down *oh mighty abs god* :lol: :D :wink:
  • 0

Persistence is a measure of faith in yourself
User avatar
schmanman
Major General
Major General
 
Posts: 1685
Joined: Sat Mar 25, 2006 12:28 pm
Location: Michigan,U.S.A
Country: United States (us)
Reputation: 0

Unread postAuthor: MrCrowley » Sun Mar 11, 2007 9:57 pm

Pete Zaria wrote:Sorry, I have to agree with the others, 1,000 yards is nearly impossible for a gun with a 3/4" valve at 80psi. If you fired it from the top of a mountain, at a 45 degree angle, with the wind behind you, you might get 1000. My best gun can get a little over 350 with the right projectile...

Peace,
Pete Zaria.



*Cough* ah um he said 1000feet not yards *cough* :P
  • 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: rejeanboucher » Wed Apr 04, 2007 11:16 pm

I forgot to follow up on my post, too many projects on the go.
Sorry if I offended some of you with my choice of wording & font style in the subject heading. To address some of your responses:
- it was very solid ¾ inch MDF board (not particle board);
- distances are estimated but I am sticking with well over 1000 ft. Will eventually confirm distances at our local RC flying field with a GPS reading. The barrel was angled at 45 degrees;
- I am so impress with its apparent muzzle velocity that I am tempted to build a simple ballistic pendulum to quantify some results; and
- Piping is solid core ABS schedule 40. I opted for ABS over PVC because for me the failure mode of splitting was a more desirable feature then having sharp pieces of PVC. Plus PVC is much more affected by the Canadian environment and to rough handling.
I have access to fighter jet tire inflation safety cage rooms and will eventually make up three test sample ABS chambers and pressurize them to failure.
  • 0


rejeanboucher
Private
Private
 
Posts: 2
Joined: Mon Feb 19, 2007 1:18 am
Reputation: 0

Unread postAuthor: frankrede » Wed Apr 04, 2007 11:58 pm

I tip my hat to you.
Well done.
  • 0

Current project: Afghanistan deployment
User avatar
frankrede
Lieutenant General
Lieutenant General
 
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Reputation: 0

Return to Pneumatic Cannon Database

Who is online

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

Reputation System ©'