Double Wye
Posted: Sat Feb 12, 2005 5:41 pm
<div align="center">DOUBLE WYE
Provided By - Evildude
The heart of this gun is the 2 inch double wye. This combustion gun works differently from most. This gun has 3 spark gaps, one at the end of each chamber branch. Many spud guns have multiple spark gaps. It's been figured that for large chambers, this would help create a faster combustion since there's more than one place for the fire to start.
This gun uses 3 spark gaps for a different reason. Each spark gap starts a separate combustion that is isolated from the other two for the majority of the combustion sequence. Each flame front travels forward towards the breech. At the last moment, the three separate flame fronts converge all at once upon the breech.
My theory behind this concept is based upon what I know about combustion chamber efficiency in automotive engines. An efficient combustion chamber, such as a "hemi" design, has the spark start at the top of the combustion chamber, and the flame front travels downward towards the piston, which can be compared to a projectile.
I've noticed on many combustion guns that the spark gap is placed towards the center of the chamber, or many spark gaps spread evenly throughout. It would be hard to confirm unless I had several clear guns and a high speed camera, but I imagine that in a gun like this the combustion would be traveling in many directions. In a central spark gun the flame fronts would be going towards both the front and back, with 3 sparks there would be more separate flame fronts traveling different directions that collide with each other.
I wanted to create a design where the flame front would travel in just one direction, which would be the breech, but not have to travel a long distance to get there. That's how this gun was born.
It has impressive power for it's size. That's a 5 foot long sdr-21 1.5" barrel I have on it in that pic. I haven't precisely measured, but that barrel gives it somewhere around a .65 to a .8-1 C:B ratio. With no projectile it makes an unusually high and sharp sounding CRACK for a spud gun. When I fire a golf ball out of that bad boy, it makes very little sound and has a tremendous recoil for something of that size.
I have an old 2" x 2.5' long combustion gun I called the "boom stick" It has a single spark gap in the back and has almost identical displacement to my new WYE gun. However when I fire a golf ball out of it with the same barrel, I don't get near the same recoil or power.
Soon I plan to put a chamber fan and propane injection on this thing. I need to get a chronograph soon, I think I remember hearing of where I could get a refurbished one for around $40 right? Ok, I'm tired of talking now and I'm sure you are too. I'll keep you guys posted with what I'm able to do with this thing.
Provided By - Evildude</div>
Provided By - Evildude
The heart of this gun is the 2 inch double wye. This combustion gun works differently from most. This gun has 3 spark gaps, one at the end of each chamber branch. Many spud guns have multiple spark gaps. It's been figured that for large chambers, this would help create a faster combustion since there's more than one place for the fire to start.
This gun uses 3 spark gaps for a different reason. Each spark gap starts a separate combustion that is isolated from the other two for the majority of the combustion sequence. Each flame front travels forward towards the breech. At the last moment, the three separate flame fronts converge all at once upon the breech.
My theory behind this concept is based upon what I know about combustion chamber efficiency in automotive engines. An efficient combustion chamber, such as a "hemi" design, has the spark start at the top of the combustion chamber, and the flame front travels downward towards the piston, which can be compared to a projectile.
I've noticed on many combustion guns that the spark gap is placed towards the center of the chamber, or many spark gaps spread evenly throughout. It would be hard to confirm unless I had several clear guns and a high speed camera, but I imagine that in a gun like this the combustion would be traveling in many directions. In a central spark gun the flame fronts would be going towards both the front and back, with 3 sparks there would be more separate flame fronts traveling different directions that collide with each other.
I wanted to create a design where the flame front would travel in just one direction, which would be the breech, but not have to travel a long distance to get there. That's how this gun was born.
It has impressive power for it's size. That's a 5 foot long sdr-21 1.5" barrel I have on it in that pic. I haven't precisely measured, but that barrel gives it somewhere around a .65 to a .8-1 C:B ratio. With no projectile it makes an unusually high and sharp sounding CRACK for a spud gun. When I fire a golf ball out of that bad boy, it makes very little sound and has a tremendous recoil for something of that size.
I have an old 2" x 2.5' long combustion gun I called the "boom stick" It has a single spark gap in the back and has almost identical displacement to my new WYE gun. However when I fire a golf ball out of it with the same barrel, I don't get near the same recoil or power.
Soon I plan to put a chamber fan and propane injection on this thing. I need to get a chronograph soon, I think I remember hearing of where I could get a refurbished one for around $40 right? Ok, I'm tired of talking now and I'm sure you are too. I'll keep you guys posted with what I'm able to do with this thing.
Provided By - Evildude</div>
i'm pretty sure it would have a high chance of exploding though!!! i have a 1.6 ft combustion chamber but three would be way better
