stevenarroyo wrote:i try to find pictures of the spark gap.
and ya i didnt add the 2 elbows into the math.
I just did a quick and dirty and it looks like you're somewhere in the 1.6-1.7:1 range. You need to account for another couple of chamber inches in your couplers on both ends as well.
Another foot or 2 on your barrel would make a noticeable difference in your performance.
Posted: Thu Oct 23, 2008 5:06 pm
by stevenarroyo
what??? how????
i just this tool to help me found it out.
O and it also said i need about 40 psi of propane and i really only need 25psi.
Well you won't in it's present configuration. You could cut the barrel off and replace it with a cam coupler or PVC screw adapter and would allow for removal of your barrel. I was really being more rhetorical about lengthing your barrel.
By my rough calc, you have 110 - 115 CI of chamber volume including the rear U and about 68 CI of barrel volume.
Posted: Thu Oct 23, 2008 5:30 pm
by stevenarroyo
OK i an just going to leave it how it is.
finish my big cannon I've been working on for some time and then maybe make one more before i leave to study.
Posted: Thu Oct 23, 2008 5:36 pm
by nivekatoz
That cannon is spatacular. I really like it.. I really like how clean the wiring is. Good job.
Posted: Thu Oct 23, 2008 5:40 pm
by starman
OK that's fine. You could easily build another strip that incorporates dual gaps....another noticable performance improver....center of the chamber spread equidistant from the ends.
In looking at your meter again, it does seem a little largish for your chamber so a relatively low psi setting for the meter pressure seems reasonable. I have a meter about the large on a gun with about double that chamber size and requires about 70 psi.
Posted: Thu Oct 23, 2008 5:41 pm
by stevenarroyo
thanks nivekatoz
yes i like how the wiring is all clean and does not show to much of it
Nice look! I really like the way the handles are configured. You should really come up with a way to house the propane tank on the gun somehow. Perhaps attach it to the 180 degree elbow vertically so that it won't flood your meter.
Did you use glued PVC on the elbow or threaded, it looks glued. The reason I ask is it's kind of nice if you need to improve or change something if it's threaded rather than fixed. Makes it a lot easier to change the barrel size, length and configuration.
One last thing that hasn't already been asked, how does it shoot? Do you have any damage shots?
Posted: Fri Oct 24, 2008 12:08 pm
by stevenarroyo
ya i'll be mounting the propane tank soon.
the barrel is glued in.
i have a video of it firing, but just with a a bag to just test what amount of propane i need to use. there's a link for u to see the video.
Posted: Sat Oct 25, 2008 1:28 pm
by 88pathoffroad
I made my inline combustion with cellcore PVC and it works fine. I've fired lots of spuds through it already...
Posted: Sat Oct 25, 2008 2:16 pm
by stevenarroyo
thanks 88pathoffroad
thats good to know, i have not fired a potato out of mine, am planing on doing so soon. maybe tomorrow?!? i dont whenever i do i'll record it and show every1 here
Posted: Sat Oct 25, 2008 3:27 pm
by starman
88pathoffroad wrote:I made my inline combustion with cellcore PVC and it works fine. I've fired lots of spuds through it already...
Maybe so... doesn't make it a good practice.
Steven, this is not something to take solace in.
Posted: Sun Oct 26, 2008 6:18 pm
by stevenarroyo
don't worry starman
i know i always try to get the pressure rated stuff. but sometimes they just don't have everything i need pressure rated.
yes i like how the wiring is all clean and does not show to much of it