Single location, close proximity drip


I want to preface this post with acknowledgeing that there is a post that may at first seem the same as this that is entitled "rain drops." Heres my question though- In a black box theatre with the audiance in close proximity i want there to be a leak from the cieling. the show takes place in a basement and there is supposed to be a few drops at the beginning and then it is supposed to stop and then a few drops at the end again. This is where this post differs from the other post. If the drops of water are not supposed to fall throughout, then simply using clamps on a tube will not work as being able to stop the water will be impossible. The idea of using a pump connected to tubing would be the next logical step. However, i dont think this would work for a single leak. if there is only one hole then the pressure would be such that you would get a stream out of that hole. We have done showers before, and that works because there are so many holes that it drips out appropriately, but with a single hole that just wont work. It seems that the best solution would be to get an IV drip from a hospital, unfortunantly the hospital isn't so willing to just hand them out to anyone that asks. Any thoughts on the matter?
You could not put in a valve of some sort to reduce the pressure?
That IV drip is deceptive. In the IV, there is little if any air getting into the system. The fluid in the tube (below the drip) flows primarily by gravity. As the fluid flows from the tube it draws a vacuum and more fluid is withdrawn from the IV bag/bottle. The drip that one sees is a function of the small diameter tube, vacuum effect, and small flow rate that is controlled by the little valve below the drip. The flow control on the drip rate is on the tubing below, not the drip nozzle or supply.

I’ll toss out a few ideas: set an eye-dropper with just the water you need and attach tubing to the top end of the dropper, then run tubing to your remote location and put the bulb or syringe there. In this system, only the dropper has water, the tubing and bulb are full of air; whatever apparatus works, install two, one for the first set of drops and the other for the second set of drops. (This assumes that you have access to the drip points prior to every performance. But with two people, you could fill the dropper without disconnecting anything.) (Your local friendly chemistry teacher should be able to help with tubing, droppers, and air bulb.)

Use a squeeze bulb or syringe to deliver the water through a tube full of water; If you are using long tubing from a remote location, terminate the end of the tube at the drip point upward into the top of another narrow tube/ cup with a hole at the bottom – the air gap and upward orientation will eliminate the siphon effect and eliminate excess water (filling this system may be problematic); instead of an open hole at the drip point, provide a vertical rod/nail at the hole for the water to run down and form a drop.

[Also: With one hole, a stream will only form if there is enough water and pressure. With a squeeze bulb or syringe, you can control both. (For example, crack open the valve on a faucet and watch the drip slowly form…) ]

A little trial and error and you should be able to come up with something. Timing and the cue may take a little practice.

I assume that you have no means of getting above the place you want to drip from during the show, hence black box, etc......

the syringe really sound like a good idea. if you need lots of the tubing marine suplie or maybe even hard ware stores may carry it. i know i boagh some for an ant farm i once owned, i just forgot where i purchased it.
I don't know about your hardware store, but I know for a fact that the hardware store near where I live always has lots of tubing. Just go to your local hardware store and pick up some black tubing that will fit the syringe. Then run it to the location where you need the drips. (Of course, being the person that I am, I would build an electronic syringe pump to electronically release the drips in a consistent manner, but that's just the crazy inventor me!)
If it were me, instead of buying feet upon feet of tubing, I'd just borrow some garden hose and run it the majority of the distance and just reduce it down on either end. The only real problem I see with the though is keeping the garden hose filled with water, but that really just depends on how you set it up.
McMaster and Grainger both should sell syrringes and small PVC tubing cheaply.

Pull back some on the plunger and it ensures there is no drip, push down on it and you regulate the flow. Smaller dia. tubing is easier to control by way of a single drip coming out at a time. Since there is only one outlet for the water, it should also be easy to counteract gravity and uncontrolled drips.
For about $20.00 you can purchase 24 v sprinkler valve from Home Depot. Use a resovoir of some type, ( I love modifing 5 gallon buckets), and plumb it to the sprinkler valve. Using standard 1" - 3/4" Pvc Pipe and an end cap, expirement with different Diameter drill bits on the end cap. Start small, REAL SMALL, it doesn't ake a big hole for a big drip. Depending on the amount you drip the one bucket < or whatever you use > may last the run of the show. If not you can Plumb directly to the valve , as it is rated to resist the head pressures of standard water systems. The advantage of this system is that you only have a small low voltage wire < 16 - 18 ga zip > running to you booth or effects station. Beside trying to shove water through a tube with a syringe from 20 feet away is sort of like pushing a rope uphill.
You can get I-V drip bags from the medical supply stores. Just go in with a business card and tell them what you are using it for and they may help you out. Offer them free tickets and tell them you will acknowledge them in the program and you may get it for free.

If that does not work get a syringe and you can control the drops that way. You can get one from most feedstores or even the medical store.

Have fun with it.


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