max length of hose for moded valve

[judgment_arms]

What is the maximum safe length of a hose for a pneumatically modified sprinkler valve?
Would 3 to 4 feet be to long?

[Infernal2]

Do you mean as part of your pilot volume?

[rna_duelers]

I have found that having a hose about 30cm in length reduces power by quite a lot.So the shorter the better.

[judgment_arms]

Will a hose of 3 feet in length decrease the performance enough to make it less effective than an electronically actuated sprinkler valve?

[Tyro]

I don't see how having a longer hose will make a difference.
Because the Pressure Above the diaphragm would go into the hose as well as in the space over the diaphragm.
When you open the valve (blowgun) The Volume of air that fits into the space over the diaphragm only has to be moved, the rest comes out regardless. As the pressure under the diaphragm will be greater it will push the diaphragm up.(will it not?)

I don't think the hose will matter in any other way then that it will take longer to fill the space over the diaphragm and the hose, then if you only had to fill the diaphragm. I'll draw a diagram maybe if you don't understand.

[judgment_arms]

Yes, well I had one of those coiled hoses on one of my other cannons and it worked great, as an air-horn… and other people have told me that “more hose = more honk” or something like that…

[Tyro]

Yeah well i don't think it would effect how quick it would actuate!

[CS]

judgment_arms, as I cant personally testify that a 3-4ft hose would work, Id suspect it would. Im pretty sure, because I think ive seen some pneumatically modded sprinkler valves close to that length. I remeber someone posting there troubled sprinkler valve and they had a 25ft fricken' coil hose hooked up to it...

As rna_duelers stated a longer hose will decrease performance, since such increases the venting volume, and leaves your venting valve at a constant.

Tyro, it does. As I said above it increase the venting volume. Since the increased volume the pressure drop will be slower then that of a sprinkler with a shorter hose.

As to anyone who cares to hear, if you both want performance, and want to fire remotly. Secure your blowgun via a close nipple. Then fasten a string to the handle of the blowgun. Works and you dont lose performance [Actually it might since opening time is slower, but whatever]. I did it on one of my customers guns so he could do testing with it.

[boilingleadbath]

Oh, Oh!
I have a animated .gif consisting of a couple dozen GGDT simulations of a sprikler valve (valve position vs. time vs. [on the movie time axis] pilot volume).

...or, well, I had it at one point in time. Seems it's commited suicide or something.
Oh well, not a problem: I still have the source frames. Just a matter of reanimating it.