New Member/ Will this work

Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
eskimo643
Private
Private
Posts: 4
Joined: Sun Feb 22, 2009 4:42 pm

Sun Feb 22, 2009 6:02 pm

So just joining. Live in the U.S. This is not my first potato gun in fact 4th one. So I decide to increase they power, and make i into a effective golf ball shooter.

So i uploaded a rough plan. I plan on buying an electric bbq ignitor and wire ignition spots in both chambers.Just wondering if this will work, and if its is dangerous or increasing potential of it exploding

i made it as an attachment
Attachments
2-22-2009 6-02-43 PM.jpg
2-22-2009 6-02-43 PM.jpg (34.82 KiB) Viewed 2246 times
jmeyer1022
Specialist 2
Specialist 2
Posts: 200
Joined: Sun Nov 09, 2008 4:50 pm

Sun Feb 22, 2009 6:24 pm

I believe boogieman of Advanced spuds made one with design similar to this and it was less powerful than a straight inline. Please go into more detail with your drawing because I can barely tell what you are talking about label each part such as:
Image

Color coordinate, label each part so on and so forth. Good first effort though, keep it up.
User avatar
Lentamentalisk
Sergeant 3
Sergeant 3
Posts: 1202
Joined: Tue Aug 07, 2007 5:27 pm
Location: Berkeley C.A.

Sun Feb 22, 2009 6:27 pm

That will be no better than a single chamber twice as long. Besides, it will be much bulkier. With such a huge chamber to barrel ratio, you won't see much of an increase either.
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
Radiation
Specialist
Specialist
Posts: 183
Joined: Wed Jul 09, 2008 10:57 am

Sun Feb 22, 2009 7:03 pm

First rule of life and spudding, more does not = Better. More is more. If you want better performance try using a higher tech approach. Are you using hairspray? If so try a more advanced setup like propane metering. You WILL get better performance there. Fan, stungun ignition etc. I will go into more detail if you want to learn more!

Welcome to spudfiles
I void warranties.

The Gauntlet of Clara Ann
TurboSuper
Corporal 5
Corporal 5
Posts: 986
Joined: Thu Jun 16, 2005 1:44 pm
Been thanked: 1 time

Sun Feb 22, 2009 7:11 pm

Seems like a fancy approach to a basic idea. I'm not sure if it will increase power, may just make it louder.
"If at first you dont succeed, then skydiving is not for you" - Darwin Awards
User avatar
ramses
Staff Sergeant 2
Staff Sergeant 2
United States of America
Posts: 1679
Joined: Thu May 29, 2008 6:50 pm

Sun Feb 22, 2009 7:57 pm

I would either upgrade to a longer, 4" bore single chamber and possibly do it over-under style(I don't care how weird that may have sounded). you could probably put a fan in the chamber for what you would save in parts for the "Y", the extra cap and cleanout, etc.

If you wanted to do it that way, you would need a cleanout cap on both chambers, and you may as well use some 45 degree elbows by that "Y" fitting, so it looks less weird.

you would get much, MUCH better performance from a longer barrel.

Welcome to Spudfiles!!!
POLAND_SPUD wrote:even if there was no link I'd know it's a bot because of female name :D
User avatar
jimmy101
Sergeant Major
Sergeant Major
United States of America
Posts: 3199
Joined: Wed Mar 28, 2007 9:48 am
Location: Greenwood, Indiana
Has thanked: 5 times
Been thanked: 17 times
Contact:

Mon Feb 23, 2009 1:45 pm

I doubt the "Y" configuration will behave any different than a single chamber of the same volume and pipe ID.

The "Y" will be a PITA to fuel and vent. The "Y" fitting is most likely a DWV only part, not pressure rated. The "Y" fitting will be subjected to the full recoil load, which is probably more of a problem than is the peak chamber pressure.

"Just wondering if this will work, and if its is dangerous or increasing potential of it exploding" The maximum peak pressure in a combustion spud gun is basically independent of the gun's geometry. Worse case scenario is the round jams in the barrel and the chamber pressure peaks at about 120 PSIG or less (propane in air at 1x, butane, MAPP etc are essentially identical). The Pressure will drop down to about 1 ATM in less than 1 second or so of ignition.

If you want to boost performance go with a larger ID chamber. Multiple sparks. Chamber fan. Metered fuel.

After all those mod's the next would be a burst disk and then a hybrid.
Image
Post Reply