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 71 users online :: 4 registered, 0 hidden and 67 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

The Hammer Shotgun

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

The Hammer Shotgun

Unread postAuthor: Novacastrian » Thu Feb 21, 2008 1:04 am

I believe this to be a first for Spudfiles, a nearly all clear Hammer Piston Pneumatic.
This was a relatively easy build, taking about 4-5 hours to complete. The chamber is made from Polycarbonate, as such the pressure used is only limited to how lucky you are feeling, i would feel safe with a working pressure of around 200psi. There are no parts that can shatter if it were to fail.
The end caps are made from Acetal as is the piston, the sealing face is Polyurethane as is the bumper. The barrel is Acrylic.

There were two reasons for building this, 1. Coolness points 2. To show noobs exactly how these types of guns work. More for the coolness factor though :P

The barrel is 16mm, as such it is perfect for marbles, i'll be making my own ammo so i'll use marbles as the tip. The chamber is just under 2". Velocity-fast.
Image
Whole cannon
Image
Piston extended
Image
Piston in fire mode

A shout out to JSR for giving me the idea of the Hammer Piston :D
  • 0

America, the greatest gangster of all time. With 200 million odd foot soldiers at it's whim and call.
When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.

Novacastrian
Major General
Major General
 
Posts: 1604
Joined: Sat Aug 11, 2007 6:59 pm
Reputation: 0

Unread postAuthor: MrCrowley » Thu Feb 21, 2008 1:09 am

:shock:

Coolness factor = ∞

No really, that looks great. How's performance?
  • 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: Killjoy » Thu Feb 21, 2008 1:10 am

Damn that looks cool. Funny, I just finished a hammer piston valve prototype a couple weeks ago, but you beat me to the posting.

Excellent job once again.
  • 0

Stanford Class of 2012

"In the end our society will be defined not only by what we create, but what we refuse to destroy"- John Sawhill

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

Unread postAuthor: Lentamentalisk » Thu Feb 21, 2008 1:17 am

sweet!
My only comment is that you need to stop making such really cool cannons, its embarrassing the rest of us.
  • 0

Do not look back, and grieve over the past, for it is gone;
Do not be troubled about the future, for it has not yet come;
Live life in the present, and make it so beautiful that it will be worth remembering.
User avatar
Lentamentalisk
Brigadier General
Brigadier General
 
Posts: 1202
Joined: Tue Aug 07, 2007 5:27 pm
Location: Berkeley C.A.
Reputation: 0

Unread postAuthor: Novacastrian » Thu Feb 21, 2008 1:30 am

MrCrowley wrote:How's performance?


To say that i was surprised at the performance is an understatement.
I tested it today at around 100psi and even with light weight plastic rod as ammo it is out of sight before you get to see it.
With another round i used (brass hollow ass) the spray can i was shooting at said "Holy crap, this is gonna hurt" then got blasted in a puff of blue paint :P
I will guess that the velocity is around 600fps but it's only a guess.
I will post some damage pics for you guy tomorrow if all goes to plan.
Cheers for the great head swelling comments too, always makes a bloke feel good!
  • 0

America, the greatest gangster of all time. With 200 million odd foot soldiers at it's whim and call.
When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.

Novacastrian
Major General
Major General
 
Posts: 1604
Joined: Sat Aug 11, 2007 6:59 pm
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Thu Feb 21, 2008 1:31 am

Once again you leave me gobsmacked, that is just beautful!

must-get-hands-on-lathe!

My one very small gripe is that due to the low-ish pressure, I would have made the chamber bigger. Also, is the portion of the piston that seals against the barrel airtight? Because if so, I think it could be impeding the hammer ìdea's function and working more like a conventional piston, perhaps you should drill a few holes in it?

One last point, you can't show us something like this without a video :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: Novacastrian » Thu Feb 21, 2008 1:40 am

jackssmirkingrevenge wrote:My one very small gripe is that due to the low-ish pressure, I would have made the chamber bigger. Also, is the portion of the piston that seals against the barrel airtight? Because if so, I think it could be impeding the hammer ìdea's function and working more like a conventional piston, perhaps you should drill a few holes in it?
:D


Point/s taken, maybe i will look at modifying the piston, i get what you are saying about it acting as a normal piston, yes it is airtight but i can as you suggested "put a few holes in it", bloody drilling holes in it, i'll have to make the holes look pretty! :D :P

Vids will happen too.
  • 0

America, the greatest gangster of all time. With 200 million odd foot soldiers at it's whim and call.
When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.

Novacastrian
Major General
Major General
 
Posts: 1604
Joined: Sat Aug 11, 2007 6:59 pm
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: jackssmirkingrevenge » Thu Feb 21, 2008 1:48 am

It doesn't have to be holes, you could just cut trim the circumference like so:
  • 0

Attachments
piston.gif
piston.gif (1.98 KiB) Viewed 1900 times
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: Novacastrian » Thu Feb 21, 2008 2:10 am

What i'll do is cut six grooves around the perimeter, after i make a new front half. I want to remove the o'ring to reduce friction and the current one will not suffice as it is too loose a fit without the o'ring. Thanks JSR.
  • 0

America, the greatest gangster of all time. With 200 million odd foot soldiers at it's whim and call.
When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.

Novacastrian
Major General
Major General
 
Posts: 1604
Joined: Sat Aug 11, 2007 6:59 pm
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Thu Feb 21, 2008 2:15 am

That would work too, remember the front portion only has to be big enough to seal over the barrel, and contact the chamber wall enough to be stable, so the more material you remove the lighter it will be and the quicker it will open :)

For those who might be wondering what this whole "hammer piston" malarkey is, this is how it works:

Image

Also, do you have a bumper to cushion the impact of the piston against the chamber endcap? Granted the piston does provide a "braking effect" but I'd still put some rubber there to soften the blow.
  • 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: clide » Thu Feb 21, 2008 2:32 am

Darn I need to stop slacking, you beat me to posting my clear piston valve that I built months ago. :(
But I don't have the cool factor a clear barrel to go along with it. Oh well I still got some tricks up my sleeve. :wink:

Nice work on the gun, looks really great.
  • 0

<a href="http://gbcannon.com" target="_blank"><img src="http://gbcannon.com/pics/misc/pixel.png" border="0"></a>latest update - debut of the cardapult

clide
Donating Member
Donating Member
 
Posts: 785
Joined: Sun Mar 06, 2005 3:06 am
Location: Oklahoma, USA
Reputation: 0

Unread postAuthor: Novacastrian » Thu Feb 21, 2008 2:48 am

clide wrote:Darn I need to stop slacking, you beat me to posting my clear piston valve that I built months ago. :(
But I don't have the cool factor a clear barrel to go along with it. Oh well I still got some tricks up my sleeve. :wink:

Nice work on the gun, looks really great.


I beat the infamous Clide!!

Any chance of seeing your creation? :P
  • 0

America, the greatest gangster of all time. With 200 million odd foot soldiers at it's whim and call.
When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.

Novacastrian
Major General
Major General
 
Posts: 1604
Joined: Sat Aug 11, 2007 6:59 pm
Reputation: 0

Unread postAuthor: MrCrowley » Thu Feb 21, 2008 2:55 am

Infamous? What's he done now... :D
  • 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: jackssmirkingrevenge » Thu Feb 21, 2008 3:43 am

MrCrowley wrote:Infamous? What's he done now... :D


Shown a penchant for ventilating ceilings? :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: SpudFarm » Thu Feb 21, 2008 12:00 pm

that just as to be cool if you put in some LED lights. think this
"at night load you cannon and light the LED's then shoot and there becomes fog in there so you can see the light in a good way"

anyway AWSOME creations you got:)
  • 0

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

Next

Return to Pneumatic Cannon Database

Who is online

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

Reputation System ©'