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View Full Version : pic: Art's other cool toy - a SnowGun!


artdutra04
11-29-2005, 06:18 PM
[cdm-description=photo]22343[/cdm-description]

Billfred
11-29-2005, 06:20 PM
Internal thought #1: DUDE! AWESOME!
Internal thought #2: How do you build/run one?
Internal thought #3: Is it cold enough to run one in the back garden of Preston?
Internal thought #4: Say, let's check Dashboard...(lows after tonight: 34-33)
Internal thought #5: Blast.

Elgin Clock
11-29-2005, 06:21 PM
I want a copy of them plans.. like.. now!!! lol

Awesome thing to have.

But seriously? White paper.. CD.. upload..

You get what I'm sayin'! :)

Ian Curtis
11-29-2005, 06:22 PM
Ooh, now that is cool. I live in a coastal town that it rains often enough to melt the snow (which means we get out of school earlier than the rest of the state) but it's no fun sledding. I can just see the faces of people who drove by your lawn.


Five dollars says you get another Billfred Seal of Approval (tm).

Adam Richards
11-29-2005, 06:27 PM
Hmm... how hard do you think it would be to install a cooler into one of these things?

Snow in 65 degree weather perhaps? :cool:

Jessica Boucher
11-29-2005, 06:28 PM
Geez, doesn't that area of CT get enough snow ALREADY? We don't need you encouraging Mother Nature :p

But seriously, that is awesome, and I'd kill for Christmas Morning snow..I can't remember how long it's been since we had one. How much to do my lawn? ;)

Wayne C.
11-29-2005, 06:33 PM
any chance of dropping by my school some late night and leaving a few feet? I could use a day off..... ; )


WC :cool:

Jeff Rodriguez
11-29-2005, 06:34 PM
I smell a senior prank.

Wetzel
11-29-2005, 06:47 PM
So, where are the plans for this thing, or at least a discussion of air/water ratios.

Wetzel

KathieK
11-29-2005, 06:59 PM
Keep it away from West Hartford (CT) Art. I'm the one they wake up in the morning to put the closing announcements on the college website! :(

Seriously, snow guns are cool. I like marshmallow guns, too. Had a blast ambushing my son a couple of weeks ago!

Jay H 237
11-29-2005, 07:37 PM
Those are fun! :) We did one on a small scale at work with leftover/scrap parts. It was smaller than the one you have though.

You need a constant regulated compressed air supply, a constant regulated cold water supply with a misting nozzle, a venturi, and a section of pipe to act as a mixing chamber.

The venturi creates a cyclone of air in the pipe and as the cold water mist is added you create snow. You have to adjust the water and air supply to get it right otherwise it just makes a watery mess.

The one we had at work isn't around anymore so either someone tossed it thinking it was scrap (right back where it was born from :rolleyes: ) or someone took it home to play with.

KarenH
11-29-2005, 07:45 PM
Hmm... how hard do you think it would be to install a cooler into one of these things?

Snow in 65 degree weather perhaps? :cool:
Unless you install refrigeration coils under your lawn, roof, etc., your snow would melt too fast to be worthwhile.

Guess you'll have to settle for spreading white quilt batting on the front lawn. ;)

Jay H 237
11-29-2005, 07:53 PM
I found a site with diagrams of how to make them.

Here's an internal (http://www.snowathome.com/internal_mix_page2.htm) and an external (http://www.snowathome.com/external_mix_snowmaker.htm).

Please be aware that adding a snow machine onto your robot is not allowed by FIRST due to possible playing field damage and is also bad GP. :p

sanddrag
11-29-2005, 08:02 PM
Well, it'll never be cold enough to do that here, but where do you get such a long lasting supply of compressed air? Surely this thing would empty a tank faster than a compressor could fill it, no?

Jay H 237
11-29-2005, 08:30 PM
Well, it'll never be cold enough to do that here, but where do you get such a long lasting supply of compressed air? Surely this thing would empty a tank faster than a compressor could fill it, no?

There are compressors that put out 20 or more CFM. They are the industrial ones that you find from Quincy, Eaton, IR, and Dayton to name a few. These aren't the typical ones the average person has, nor available from places like Sears. The 2 stage pump models would start around $1500 and up. There's also screw drive compressors but they're really expensive. Most of these compressors have continous duty cycles.

You could do this on a smaller scale with a compressor that the average person has. Don't expect to cover the whole yard but you could do a small section. You most likely will have to cycle the snow gun since the compressor may have to play "catch up" at times. The climate also plays a large role. Here in Connecticut with our temps I'm sure I could do a section of my yard with my 26 gallon CH compressor (6 CFM) since it won't be melting fast. I would have no success in Florida though.

Greg Marra
11-29-2005, 08:39 PM
Holy sweet!

I could use one of those on this nice hill in town...

artdutra04
11-29-2005, 10:54 PM
Well, it'll never be cold enough to do that here, but where do you get such a long lasting supply of compressed air? Surely this thing would empty a tank faster than a compressor could fill it, no?
Right now, the compressor that I am using is rated at putting out 9.0 CFM at 40 PSI and about 7 at 90 PSI, but, the compressor is like 20 years old, so I have no idea what the actual output is. I'd guess that is about 8 CFM at about 75 PSI.

If you were to make a snow gun, you have to make sure that your air and water pressure is about equal, give or take about 5 PSI. Otherwise, you may force the higher pressure fluid down the other hose. I originally tried to use the air at 90 PSI, but when you opened the faucet in the house and heard compressed air coming out, something's wrong! :yikes: Luckily, I have city water (not a well) and I live at the bottom of a hill with a large subdivision, so the water pressure at my house is very high. (It was about 110 PSI before it gets to a pressure reducer, which drops it down to 75 PSI.) If you have low water pressure, I have seen people on the Internet who have used pressure washers to get their water pressure up.

Here is the basics of the design. When a compressed gas is allowed to expand very quickly, it drastically reduces the temperature of the air around it, as it tries to absorb energy from it to get to a higher state. So when the compressed air comes out of the snowgun at the same time as water, the expanding air takes lots of energy away from the water, so the water freezes into snow. Theoretically, if you were to have enough compressed air coming out of the snowgun, it would take so much energy away from the air, that you could make snow above the freezing point. I have seen some ski resorts be able to make snow at up to 38 F.

Everything in my snowgun is made of 3/8" NPT pipe, all available at Home Depot for exactly $24.93. At least it was a year ago when I bought all the parts. If you were to make one, be sure to use the Teflon Tape on all the joints, because any water leaking out will make giant icicles. Here is basically all that it took to make it.

http://img251.imageshack.us/img251/8956/snowgunplans6wz.jpg

The only thing is that you should buy a ton of end caps where the snow comes out. You may decide to make different sized holes for different weather and temperature. I decided that in order to try to get even more snow out of the snowgun, I would add the 90 tee and drill five holes into the side of the pipe. This would allow the snow to get more air contact when it came out, and would allow for even more water (and hence snow) to come out of the snowgun.

Last year on Christmas, I was only able to make about an inch and a half in about half of my front yard. The temperature had barely reached 27 F, so the snow was right on the edge of the slush/wet snow line. But I have been able to make seven inches once on about 150 square feet in two and a half hours, when the temperature was 7 F.

If you do build one, make sure you check it every hour or so. Otherwise, you may have tons of snow or ice build up on it, which may freeze the gun up. (Or burst your garden hose...which has happened to me three times. If you don't catch it, the garden hose will flood your front yard, and then freeze solid. This happened last year, and as a result I had eight inches of solid ice over a good part of the front yard.)

http://img418.imageshack.us/img418/2049/snowgunsnowbuildup4yg.jpg

Please be aware that adding a snow machine onto your robot is not allowed by FIRST due to possible playing field damage and is also bad GP. :p
What about the Curling + Robots = Sweet (http://www.chiefdelphi.com/forums/showpost.php?p=362430&postcount=14) game? :p

Nitroxextreme
11-29-2005, 11:29 PM
This is by far one of the best implementations of robotics knowledge for straight out fun

i was just wondering...what did you use for the nozzle end for the machine

ahecht
11-30-2005, 09:05 AM
I originally tried to use the air at 90 PSI, but when you opened the faucet in the house and heard compressed air coming out, something's wrong!

That is very very bad. If you try something like this, always make sure to use a backflow prevention device. Especially if you or your neighbors drink your tap water, you always want to prevent water from flowing from things like hoses back into your home plumbing. I'm not sure if a hose-bibb vacuum breaker would work in this case, but there are other backflow prevention devices that probably would.