Stage Rain

[bobgaggle]

I've been looking over this site for the best way to make rain, and have only found small projects like rain outside a window. For my school's production of Jekyll and Hyde, we have a 40' wide by 3' deep catwalk permanently on stage. During Jekyll's "The Way Back" we want it to rain on him as he paces the catwalk. I just wanted to bounce some ideas off everyone out there.

I was thinking to rake the catwalk deck towards upstage, maybe a 2" rake.( 8' in the air, but there's a railing, naturally.) We make a rain pipe to hang above the catwalk, and when the water falls, it rolls down the rake into a gutter installed onto the back of the catawalk. this runs to a hose off stage left to a sink we have in a closet just off stage. Of course the plywood deck would have to be waterproofed.

It wouldn't be a closed circulating system, but we have some random water pipes on the stage that are never used for anything (maybe for fire crews?) They have valves at hand level and would be prefect to run a hose up to the rain pipe (maybe with the help of a pump, if the head is too high for the water pressure)

Comments?

[Footer]

Well, I got done working with a fairly large rental set from singing in the rain about 6 months ago that has toured and been through the "ringer" a few times, so... ya... played this game. First, you will need nozzles on your rain system, simply drilling holes in PVC will not work. Also, you want to have multiple pipes, no more then about 10' long each being fed by a hose. If you make it longer, you will get drop off. We ran 2 5hp electric pumps for the show, fed by a very large agricultural tank. We of course put down a huge rubber mat under the entire rain deck for the show, and the rain deck had a built in trap with a sump pump. We never recirculated the water, it was too risky to pick up dust/dirt that could easily plug the nozzles. I would recommend getting the beefiest pump you can afford, simply lifting this huge amount of water to your batten will be hard enough. If you have any other questions, feel free to ask.

[bobgaggle]

Thanks for the advice. Let me see if i get this straight:
Water goes from tank to a pump, through the pump to the different pipes? Is there a separate output from the tank for every pipe?

what if the holes where situated on the top of the pipe? The water fill the pipe to the top and would drip around the circumference to supply a steady rainfall. In my mind this would avoid fall off. and where were the pumps situated in the system?

and i can fasten the pipes directly to the supporting I beams in the ceiling.

[Footer]

It went.... tank to pump to 4 valves that fed each hose to batten. We had two battens, one pump for each. I would give the inverted thing a try, could not hurt. We put our tank USL because it was easy to get to the pumps and things. If you have a fly space, I know some people who have taken the tank to the grid or a nearby rail and done gravity fed systems, you only have to pump the water up once then let it fall down. As far as the inverted thing, give it a try!

[jwl868]

footer4321

Just out of curiosity, why couldn't you use the potable water supply line at the venue?

The only reason I ask is that I would expect the potable water supply to be at a decent pressure (50 to 75 psig) and I would expect 5 to 10 gpm. Or was there a flow rate issue for your production?

(Seems to me that a direct connection to a water supply would be a simpler arrangement.)


bobgaggle - you may need to do some trial and error testing (like in a garage or outdoors) - primarily to figure out how much water you need and how it looks and/or if you can make it work with the available potable water supply pressure. In the big scheme of things, the pressure drop through the nozzles to get the desired effect may be as significant as the pressure to lift the water, if you are using a pump.

If you put the nozzles pointing up, you should consider what might happen if someone turns a valve the wrong way or too far, shooting a stream of water much higher than planned.



Joe

[Footer]

Originally Posted by jwl868

footer4321
Just out of curiosity, why couldn't you use the potable water supply line at the venue?
The only reason I ask is that I would expect the potable water supply to be at a decent pressure (50 to 75 psig) and I would expect 5 to 10 gpm. Or was there a flow rate issue for your production?
(Seems to me that a direct connection to a water supply would be a simpler arrangement.)
bobgaggle - you may need to do some trial and error testing (like in a garage or outdoors) - primarily to figure out how much water you need and how it looks and/or if you can make it work with the available potable water supply pressure. In the big scheme of things, the pressure drop through the nozzles to get the desired effect may be as significant as the pressure to lift the water, if you are using a pump.
If you put the nozzles pointing up, you should consider what might happen if someone turns a valve the wrong way or too far, shooting a stream of water much higher than planned.
Joe

City water supply where we were were not enough to get the volume of water we needed when we needed it. We were downtown in a good sized city, constant pressure simply did not exist. Also, keep in mind if you want an entire stage to be covered by rain, its going to take a large volume of water, way more then usually runs to any stage unless you hook up to the fire suppression system (which you should NEVER do).

[gafftaper]

I saw rain done on a set by a local pro theater recently. They wanted very drippy looking rain, not a steady downpour. They used a bunch of garden pond pvc line coiled back and forth in a random pattern about 3 feet wide. Then they hung little strings of all different lengths... perhaps some sort of tassel or fringe material from the fabric store. They drilled holes in the top. The water clings to the strings making a very interesting random drip pattern. It looked great. Not what you want for a down pour (you need nozzles there)... but great of a drippy dreary day.

They had hot 2 hot water tanks located "up there" somewhere... something most of us don't have the ability to do due to the weight but not difficult for them due to the way the building is designed (Two theater's stacked one top of each other) They filled the tanks before the show, warmed it up, then just used gravity and a small garden pump to pressurize the system.

Equity actors and their hot water rain... what wimps!

[Van]

I think what most people forget, when dealing with water is the mass involved. "All the world round, a Pint is a Pound." 8 Pints in a gallon, Be sure do double check all your math and load capacities, prior to lifting a rain rig into the air. A very "Lightweight" PVC system can suddenly get extremely heavy.
Having played with a lot of different rain/water systems I can tell you expirementation is the only way to find the look you want. low voltage controlled sprinkler valves, like you find at Home Despot, can be a godsend for control issues. Check with your Janitorial / maintenance staff to see if they have a pressure reading for your area of the building. There are lots of places on the web at which you can find formulas for computing flow rates, head pressure, etc. I found the existing pressure from our potable water supply was sufficient to run the 6 showerheads required by "Take Me Out" a couple of years ago. I did have to rig two hot water heaters in line to provide enought so the actors didn't suffer from , Ahem, Shrinkage.

[SweetBennyFenton]

I knew that show was going to make it into the conversation.

[Van]

Originally Posted by SweetBennyFenton

I knew that show was going to make it into the conversation.

I'm nothing if not predictable.