Posted: Thu Apr 10, 2008 2:04 pm
With that first design with the 3 chambers, if you build it, try and buff the fittings up together so you can't see any pipe between the four way cross and the eblows
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Thanks for all your help guys, I thought about just starting over. I glued the threads in the sprinkler valve.....uhhhh oooops. I can't move anything unless I can break the bond of the cement and unscrew it, but I doubt it. I have some good ideas now on how to make this work better.starman wrote:Then a 1" sprinkler is closer to ideal (for a sprinkler) for a 1" barrel. If you go with a 2' barrel length and keep the tank the same, you'll have roughly 2:1 c:b ratio. A 4' barrel roughly 1:1. Depending on projectile weight, both good performers.ImHUGEnJAPAN wrote:What if I reduced the bore size of the barrel? lets say to 1"
In your config, you still have a dead space issue on your back elbows. With your short barrel, that is contributing to your low performance as well. Move the sprinkler right behind the barrel.
That's what I am planning on doing. I hope lowes carries sch 40 2" pvc crosses and elbows, I think they do. I have extra pipe left over from the original construction.MrCrowley wrote:With that first design with the 3 chambers, if you build it, try and buff the fittings up together so you can't see any pipe between the four way cross and the eblows
I never thought of that, that might be a better option. I think I might try the bigger air chamber first. I'm Just curious to see what happens. Then I might change the design if a larger air chamber doesn't do the trick.judgment_arms wrote:Glued your fitting to the valve? Not a problem, cut off the pipe that attaches to them and glue the fittings in a piece of 1.5 inch PVC, it may take some sanding be it’ll work.
Well... I suppose I should consult GGDT before making statements like thatIt wont increase your power much, sorry to say.
From what I read it seems you can do it either way. It seemed to give me a slight increase in performance. It seemed that the spring was causing the valve to close prematurely and not letting all the air out of the chamber.no-limit wrote:You say you removed the sping from inside the valve of the cp-100, I was told not to do that. Guess you can't believe everything you hear here.
Sometimes the cores become a little loose, try screwing it a little tighter. If it spins really easy, that is probly why it leaks, unless of course it leaks where it's installed.ImHUGEnJAPAN wrote:Ok, I finally got to test fire the design this morning at 60 psi and I noticed a nice increase in power just shooting hacky sacks across my living room. I wanted to crank it all the way up, but I didn't want to put a hole in my wall. I shot one of the kids 2" superballs at about 10-20 psi pretty good. I decided that was a bad Idea inside....hahaha
If I doubled the barrel length from 20" to 40" this would probably be a pretty good cannon.
Now my Schrader valve is leaking......grrrrrr, as with life it's always something....lol. If I just screw the cap back on really fast it's ok. I will probably just replace it later.