CAP
- Hunt_and_Annoy
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- Joined: Sat Feb 12, 2005 1:00 pm
CAP
So me and a friend built a relatively small CAP gun using 1 liter bottles. It was really only a prototype to test the concept, and doesn't work at anything larger than like 3x, but it works. Just though I'd let you guys know. Will post pictures eventually
- Hunt_and_Annoy
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- Joined: Sat Feb 12, 2005 1:00 pm
Re: CAP
Yeah. We're buying a bigger regulator for our backpack version. In theory. We're also considering building a digital regulator.
- Drenchenator
- Posts: 807
- Joined: Fri Jun 18, 2004 12:00 pm
Re: CAP
Good job on the prototype!
What do you mean by a digital regulator? A typically regulator works using springs, so I don't really see how it can be digital versus analog here. Could you elaborate on what you have in mind? Digital readout, maybe?We're also considering building a digital regulator.
The Drenchenator, also known as Lt. Col. Drench.
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Re: CAP
He might mean those pressure switches used in air compressors. I believe you can set them to a certain pressure and they control a switch (typically, it controls whether or not an air pump is on or not); it could be connected to a sprinkler valve. I saw someone using the same setup somewhere else, but I don't remember the link.Drenchenator wrote:What do you mean by a digital regulator? A typically regulator works using springs, so I don't really see how it can be digital versus analog here. Could you elaborate on what you have in mind? Digital readout, maybe?
I wouldn't call this digital, but at least its electronic.
- SSCBen
- Posts: 6449
- Joined: Sat Mar 22, 2003 1:00 pm
Re: CAP
Interesting. I can't find any price figures but it's probably safe to assume it will cost more than an analog regulator. In my experience normal regulators have enough precision to make any differences in pressure negligible.
That might not be what he's planning though because he said he'll build it.
That might not be what he's planning though because he said he'll build it.
- Drenchenator
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- Joined: Fri Jun 18, 2004 12:00 pm
Re: CAP
I agree. Given that that site has a page for getting a quote, I'm assuming it's pretty expensive.
Hunt_and_Annoy, could you elaborate on your plans? They seem interesting enough for some discussion.
Hunt_and_Annoy, could you elaborate on your plans? They seem interesting enough for some discussion.
The Drenchenator, also known as Lt. Col. Drench.
- Hunt_and_Annoy
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- Joined: Sat Feb 12, 2005 1:00 pm
Re: CAP
I was thinking about having an electric pressure sensor which would turn on and off a solenoid valve very quickly to keep the pressure constant in the firing chamber.
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Re: CAP
That sounds a lot like what I described earlier...Hunt_and_Annoy wrote:I was thinking about having an electric pressure sensor which would turn on and off a solenoid valve very quickly to keep the pressure constant in the firing chamber.
I would just go for an analog one, like Ben used on his SuperCAP. Using an electrical system would just make it more complex and less reliable.
EDIT: I found the link I had talked about earlier. Here is a picture from here about a potato cannon that used the setup.
Last edited by aEx155 on Tue Jun 17, 2008 7:39 pm, edited 1 time in total.
- Silence
- Posts: 3825
- Joined: Sun Apr 09, 2006 9:01 pm
Re: CAP
It probably depends on the application. As limited as flow is through solenoids, there's definitely a higher flow coefficient than with a mechanical regulator. With launchers or other devices that use up a lot of air and then need more soon, it makes more sense to use a large valve than a small one, so an electric regulator may be better. But with CAP water guns and the like, which use many short bursts of water with low flow, a mechanical regulator is more suitable - it can open and close more quickly than a solenoid and it provides sufficient flow.
Well, I see why you'd want an electric regulator, since the current mechanical one may have limited the flow. But first (as you implied you would do), it's probably better to compare the flow of your current regulator with the flow of one that Ben used.
Well, I see why you'd want an electric regulator, since the current mechanical one may have limited the flow. But first (as you implied you would do), it's probably better to compare the flow of your current regulator with the flow of one that Ben used.
- SSCBen
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- Joined: Sat Mar 22, 2003 1:00 pm
Re: CAP
Interesting. I wonder where he bought the pressure switch. I'm looking at McMaster-Carr and the most reasonable part is 3460K61 which cost $23, which is half the cost he reported. The picture on McMaster-Carr doesn't look like the one in that spudgun so it's a different switch.EDIT: I found the link I had talked about earlier. Here is a picture from here about a potato cannon that used the setup.
1/4 inch regulators will have more air flow than you'll need. You don't need to spend money on anything complicated. You probably could get away with 1/8 inch regulators on pressures lower than a certain amount.
This would be a cheaper way to get higher flow regulated pressure than a simple larger mechanical regulator but for sizes that are reasonable for water guns it's more expensive than a simple regulator. The normal regulator I'm going to use in my new CAP water gun costs $18 on McMaster-Carr from what I remember and it's better than what you need Hunt and Annoy. If you haven't bought anything yet I'd suggest saving some money with a mechanical regulator.
- Drenchenator
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- Joined: Fri Jun 18, 2004 12:00 pm
Re: CAP
I understand now. I might be able to see some advantage from the flow perspective--I don't think that a regular regulator allows much flow; but then again a solenoid doesn't either. I guess it's just another viable option. Try it out.
The Drenchenator, also known as Lt. Col. Drench.