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 68 users online :: 4 registered, 0 hidden and 64 guests


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

Registered users: Bing [Bot], Exabot [Bot], Google [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

Would this make a good piston???

Post questions and info about pneumatic (compressed gas) powered cannons here. This includes discussion about valves, pipe types, compressors, alternate gas setups, and anything else relevant.
Sponsored 
  • Author
    Message

Would this make a good piston???

Unread postAuthor: ImHUGEnJAPAN » Wed Jun 25, 2008 4:00 pm

<a href="http://s273.photobucket.com/albums/jj231/YerBallsRshowin/?action=view&current=0625081649.jpg" target="_blank"><img src="http://i273.photobucket.com/albums/jj231/YerBallsRshowin/0625081649.jpg" border="0" alt="Photobucket"></a>

I was wondering if this would make a good piston

Materials:

2" diam (whatever size I need) round steel Bar stock cut to 1" to 2" length
Old mouse pad cut to proper diameter
Washer
Bolt
Nut
Nerf Ball

See picture on how it goes together.

I will also dril a 1/8" equalization hole in the piston.

The parent company that I work for has a machine shop with tons of scrap bar stock. I can easily cut to lenght any size round bar stock I need.

The nerf ball will be free floating behind the piston to cushion the steel piston from cracking the PVC when it slams back. Is this a bad Idea?
  • 0


ImHUGEnJAPAN
Corporal
Corporal
 
Posts: 77
Joined: Thu Apr 03, 2008 12:08 pm
Reputation: 0

Unread postAuthor: jrrdw » Wed Jun 25, 2008 4:08 pm

Steel is to heavy, 1/8th" eq. hole is to big.
  • 0

When life gives you lemons...throw them back they suck!
User avatar
jrrdw
Donating Moderator
Donating Moderator
 
Posts: 6540
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Country: United States (us)
Reputation: 25

Unread postAuthor: Gippeto » Wed Jun 25, 2008 4:21 pm

I'll agree with jrrdw here.


And add my .02


Nylon is fairly common and much lighter than steel. I've used it with good results.

Skip the equalization hole all together. Put a floating o-ring on the piston instead.

Blind drill the bolt hole and tap it. No need for the nut.

Scrap the nerf ball and use a couple "washers" cut from the mouse pad for a bumper.
  • 0

"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
Gippeto
Donating Member
Donating Member
 
Posts: 2394
Joined: Sat Jan 19, 2008 10:14 am
Location: The Great White North...Canada eh!
Reputation: 11

Unread postAuthor: MrCrowley » Thu Jun 26, 2008 12:13 am

No need for an equalization hole if you have no o-rings on the piston.

I'd also put a larger washer on the sealing face otherwise it will get ripped off.
  • 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: Stifler69 » Thu Jun 26, 2008 3:06 am

Omg thanks soooo soooo much i never really understood the whole concept of piston valves but now i do !!!!!!
  • 0

User avatar
Stifler69
Specialist
Specialist
 
Posts: 56
Joined: Fri May 30, 2008 11:46 pm
Location: Melbourne. Victoria
Reputation: 0

Unread postAuthor: SpudFarm » Thu Jun 26, 2008 5:26 am

he can machine out the back of it so i becomes a thin shell.
  • 0

Attachments
lettere.jpg
piston after machining.
lettere.jpg (17.42 KiB) Viewed 331 times
"Made in France"
- A spud gun insurance.
User avatar
SpudFarm
Donating Member
Donating Member
 
Posts: 2563
Joined: Sat Nov 04, 2006 9:39 am
Location: Norway Trondheim area
Reputation: 0

Unread postAuthor: psycix » Thu Jun 26, 2008 7:23 am

Steel is one of the worst piston materials due to the weight.
I'd recommend something like nylon, PVC, or if you really want to use metal: aluminum.

Use something foamy as bumper, but make sure it doesn't constrict pilot valve flow.
Dont make the piston too short, as it might jam sooner because of that.
  • 0

Till the day I'm dieing, I'll keep them spuddies flying, 'cause I can!

Spudfiles steam group, join!
User avatar
psycix
Donating Member
Donating Member
 
Posts: 3684
Joined: Mon Jun 25, 2007 7:12 am
Location: The Netherlands
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: ImHUGEnJAPAN » Thu Jun 26, 2008 7:35 am

Thanks for the feedback! I thought steel might be too heavy. I a few other ideas in mind.

Thanks agian!
  • 0


ImHUGEnJAPAN
Corporal
Corporal
 
Posts: 77
Joined: Thu Apr 03, 2008 12:08 pm
Reputation: 0

Return to Pneumatic Cannon Discussion

Who is online

Registered users: Bing [Bot], Exabot [Bot], Google [Bot], Yahoo [Bot]

Reputation System ©'