Balloon Diaphragm

A place for general potato gun questions and discussions.
User avatar
Atlantis
Corporal 5
Corporal 5
Posts: 955
Joined: Sat Sep 03, 2005 10:26 pm
Location: Florida

Sat Feb 04, 2006 1:18 am

I was wondering if instead of using a piece of rubber sheeting as a diaphragm, I could stretch and attach a balloon to the inside of the chamber somehow. Would the force of the rushing air towards the pilot valve rip through the balloon? Could I use multiple layers of balloons? Kind of non-related to the question but, could I use the rubber part of certain mousepads for a diaphragm?
User avatar
Brian the brain
Moderator
Moderator
Netherlands
Posts: 3497
Joined: Mon Dec 05, 2005 2:06 am
Location: Holland
Been thanked: 7 times

Sat Feb 04, 2006 1:53 am

Try a mouse ball..
User avatar
jrrdw
Moderator
Moderator
United States of America
Posts: 6572
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Has thanked: 39 times
Been thanked: 22 times
Contact:

Donating Members

Sat Feb 04, 2006 6:51 am

MOUSE BALLS-that must be a really really little cannon!!

depends on what kind of air pressure your looking for? a ballon sounds kinda flimsie
User avatar
saladtossser
Sergeant 3
Sergeant 3
Posts: 1234
Joined: Sat Mar 26, 2005 10:40 am
Location: Toronto
Contact:

Sat Feb 04, 2006 12:23 pm

yea, i think it will pop, you would have to use a lot of them, and each one has to be stretched in the exact same way.
better not try it, it may fire when you dont want it to.
it may work for a piston valve though
"whoa... I thought pimpmann was black..."-pyromanic13
User avatar
boilingleadbath
Staff Sergeant 2
Staff Sergeant 2
Posts: 1635
Joined: Sat Mar 12, 2005 10:35 pm
Location: Pennsylvania, USA

Sat Feb 04, 2006 4:31 pm

Ballons are pretty thin, let's say they are 5 thousandths of an inch (.005") thick - this means that they'll fail at roughly 5lbs per linear inch.
I don't know the formula for pressure failure of elastic disks, and this synthisized one will probably overestimate, because it doesn't take the stretching into effect...
Let's say you want to make a .5" barreled, 1" chambered, launcher. Chamber circumference = ~3"; tensile loading for perimiter failure 15lbs; 20psi.
For 2" chamber, that's 10psi; 4", 5psi; 8", 2.5 psi...

Most mouse-pad material is porus... and therefore won't work.
User avatar
Atlantis
Corporal 5
Corporal 5
Posts: 955
Joined: Sat Sep 03, 2005 10:26 pm
Location: Florida

Sat Feb 04, 2006 9:29 pm

I found a mousepad's with the gel cushion. It has a rubber pad on the bottom. It kinda looks like this.
http://ec.ingrammicro.de/jpg/J15Z336.jpg
Its somewhat thick, haven't really checked but it feels thick. Its very smooth on one side.
Post Reply