SpudFiles

So I epoxied the solenoid holes, and made sure that they werent leaking, but it still makes an airhorn type noise. Any idea on how I can fix it?

You need a larger pilot valve.

I believe I explained this in your other thread... you need a pilot valve with a larger flow. Try a ball valve instead of a blowgun.

JDP, I need the blowgun for this to work correctly, other wise it looks like a POS.... Plus it has to have multiple firings rather than one big shot....

Modify the blowgun. Generally, you can drill the output hole (or input; I forget) bigger, and make the internal moving part more spool like. There's an article in the wiki.

Modifying it worked... It now outputs one hell of alot more air, but still has an airhorn type sound... I cant drill it out any more other wise I may break the blowgun, but it still outputs more than it used to...

what size is you sprinkler valve?

open up the valve and get rid of the filter on the edge of the diaphragm

yea.. if you want you can grind down the shaft inside the blowgun to increase flow even more.

I know I should have added on to my other thread, but I just thought of this. I notice when I shoot my rifle, the air pressure drops by 5 psi, is it possible that the air tank connected to my rifle and the chamber that is attached to the sprinkler valve is not holding enough air to make it work properly?

If you mean your tank pressure drops by 5psi with each shot, that is unavoidable. You are letting air out with each shot. The amount of air in the tank is related to the pressure and volume of the tank (ideal gas law, PV=nRT) The volume of your tank is constant, so if air is released, the pressure must drop.

If you want more consistent shots you can attach a regulator between the tank and your firing chamber. By filling the tank to a higher pressure than the reg is set to, you can get multiple shots of the same power, rather than decreasing power with each shot.

Thats not what I mean. I think the hose I have is restricting the air flow to allow only 5 psi into the chamber, because thats how much drops from the air tank...

warhead052 wrote:Thats not what I mean. I think the hose I have is restricting the air flow to allow only 5 psi into the chamber, because thats how much drops from the air tank...

Air flow cannot restrict pressure. He knows what you mean, it's you that doesn't know what you mean The compressor resevoir is larger than that of your gun, I assume. If your tank is 2 gallons for example and your gun is 1 gallon, your compressor is at 100 psi, and you try to fill your gun up, the pressure in your tank will equilize to about 65 psi. Now with a regulator, you could put 50 psi into your gun on a 100 psi compressor charge multiple times before you need to turn the compressor back on.

Now I'm not trying to be mean or anything... but it scares me that people who aren't educated in this science are making these devices. If you don't know what you're doing... don't do it. I mean it's like the guy who thought a short piece of pipe couldn't hold as much pressure as a longer piece of the same pipe. Just know what you're doing... research always helps before you take the plunge into this hobby.

I under stand, just that I dont get why it drops only 5 psi... I need to install a pressure gauge on the chamber as well as the air tank... that way I can see the pressure without having to take off the air tank....

Crna, its a 1" valve.

Lockednloaded, will that increase flow?

JDP, I dont have a grinder....

Without a reg between your tank and chamber the pressure in each will be the same. The flow restriction of the hose will slow the time it takes the two to equalize, a good thing if you want multiple shots.

The reason your tank is only dropping 5 psi is likely because it is significantly larger than your chamber. As I said before pressure and volume are related by the ideal gas law (seriously, look into this more) PV = nRT. That stands for Pressure * Volume = moles of gas * A constant * Temperature.

Here's a sample calculation (ignoring atmospheric pressure):

Say your tank is 100 in.^3 and your chamber is 10 in.^3. Both are filled to 100psi. If we empty the air in the chamber, there is no pressure in the chamber. So the air in the tank, 100 in.^3 * 100 psi, expands to fill both the tank and chamber, reducing its pressure.
(100in.^3 * 100psi)/110in.^3 = 91psi
the same would happen again on the next shot.
(100in.^3 * 91psi)/110in.^3 = 83psi

So for my example cannon, the tank pressure is dropping between 8 and 9 psi each shot. You can do this same math for your cannon to figure out how much the tank pressure will drop for each shot, and how many usable shots per fill you can get.