Categories
SFX EFX

Pools, Waterfalls, …

However, let’s get the pool built. First, pools take a lot more water than most people realize. A small pool 10″ deep and 4’ diameter contains 78 gallons of water. 78 gallons of water weighs 650 pounds, or, at 10″ deep, 51 pounds per square foot. That is a lot of water and a lot of weight to handle. In addition the weight of scenery such as rocks or trees and the framework to hold and contain the water must be considered. Last but not least there is the live load of the actors which can add up very quickly, depending on the action or lack of it. A pair of performers weighing 120 pounds each can easily add up to one ton of impact loading if they are cavorting or dancing. If the pool bottom is directly on the main stage floor, there is rarely a problem. Most stage floors are rated at 150 pounds per square foot or higher. To exceed that loading the water, by itself, would have to be 30″ deep or greater. If the pool is built into a raised level or platform, then the scenic unit has to be built to handle the weight of the water, other scenery, and the live load of all the actors that are in or around the pool at one time.

The easiest way to create a pool is to use “pond liners” that are available at garden shops, some Home Quarters, Home Depot, et al. Smaller liners, 3’ to 4’ diameter, are usually made of a very ridged plastic and molded into shape. They are commonly 10″ to 14″ deep and irregularly shaped. While these liners look fairly strong and self supporting, they are designed to be set in the ground with soil supporting the weight of the water on all sides. If one of these molded liners is used, you must support the bottom and the lip or edge all around. Larger liners come in the form a vinyl sheet and if you have access to a used or discarded above ground pool liner, they can work also. If you have a second hand pool liner, make sure there are no leaks in the section you intend to use. Soft liners must be supported on all sides and surfaces, just like an above ground pool. Otherwise the weight of the water will pull the liner away or possibly rip it where it is fastened along the edge.

The easiest way to support a soft liner is simply to make a 3/4″ ply box (the stage floor can be the bottom). If the pool is supposed to be natural rather than man-made, build the box with as irregular a shape as possible, install the liner, and then shape the interior of the pool with real stones, astro turf etc. until the shape matches the design concept. When building a pool, it is easy to forget it once it is installed and filled. This is a big mistake because you have created a perfect place for bacteria and other things to grow. Theatre stages are also not noted for their pristine cleanliness. Dust, dirt and a myriad of other surprising things will find their way into the water. The water should be treated with a mild, non clorene pool or spa treatment to prevent any possibility of bacteria, mold or fungus growth. The reason for the non clorene treatment is twofold.

First, the clorene smell can be objectionable and is easily detected by the audience. Second, any costume that comes in contact with the water will be slowly bleached out. The water should be changed at least once a week, depending on how much contamination it gets from dust, dirt, the snow from last year’s Nutcracker……! Streams and waterfalls are two aspects of a similar problem. Both have to use a recirculating water system. Both create noise that has to be dealt with in some way. Both have to have a catch basin to collect the water for recirculating. A water fall and a stream can end in a pool, but a stream can also run off stage to a 55 gal. barrel or some similar holding and recirculating tank. Streams can be built as high tech as a fiberglass trough that bolts together in sections, or as simple as a couple of sections of corrugated culvert liner with visquene or a pool liner.

Visquene should be a last resort as it can develop leaks very easily. One rather easy method of constructing a small stream is to cut or build a series of ribs with a concave shape. Connect the ribs by laying 1/4″ ply or luan sections from rib to rib. After cross bracing and securing, line the wooden trough you have built with visquene or a soft pool liner. The support structure for a stream rarely has to be built as strong as a pool, as there is usually far less water in any given section of the stream. The greatest danger to a pool or stream is if performers have to walk or wade in them. Walking or wadding present a grave danger of puncturing or abrading a hole in whatever you have used to line the waterway. First make sure that there are no foreign objects, dirt, grit, etc. between the floor and the underside of the liner. Next place a thin, firm but soft surface such as 1/4″ ethafoam sheet or indoor-outdoor carpet, soft side up, between the liner and the support surface. Finally place a second layer of similar material, soft side down, where the walking or wading is to take place. This second layer must be weighted down, clamped or otherwise fastened to prevent a slip hazard. One way to help fasten down the layer in the stream is to use silicone caulk. It doesn’t really adhere to the ethafoam, vinyl or visquene but if left overnight before running water through the stream it will help to prevent slipping as performers walk on it. The amount of water running through a stream can be staggering.

A small stream 24″ wide and 6″ deep at the center can run several thousand gallons an hour, depending on how steep the slope is. A pump that large creates quite a bit of noise and is pumping water out at a tremendous pressure. How do you handle the noise and the stream of water that would shoot clear across your stage like a fire hose? The first trick is to reduce the amount of water needed to the absolute minimum. Build your stream as shallow as possible. Break up the flow with rocks, logs etc. Make the bottom of the stream bed a dark color with mottled, soft edged break ups, like camouflage. If performers have to wade through an area, make that a small pool, deeper if not wider. Reduce the total drop from the top of the stream to the bottom to the least amount possible. Finally, at the out put of your pump, use the principle of greatly reducing the output pressure by greatly increasing the size of the output pipe.

A simple way of doing this is to use a series of reducing couplings to increase the size of the pump output from the 1 1/4″ to 3″ that is the most common, to about 6″to 10″. If this series of pipes is in a straight line it will have little or no effect unless it is 20’ or 30’ long. Put a 90 degree elbow or two in the system, the last one just after the final increase in size. Point the final stage straight up and turn on your pump. If the water simply bubbles up over the top, you are ready to install the piping to the stream. If you still get a slight fountain (you have one heck of a pump!) more than you want, you can add another section of pipe at a still larger diameter or you can use the “barrel method”. The barrel method is simply to take your final stage pipe and aim it straight down into a 30 to 55 gallon barrel, from about 6″ to 10″ below the rim. When the barrel fills up you have effectively increased the final stage of your piping to the square inch area of the barrel minus the area of your pipe section.

The water will pour over the edge of the barrel in a flow instead of a jet. The easiest way to terminate your stream is to have it continue off stage, out of sight lines and pour directly into your holding/supply tank. This eliminates the need to pierce your stream bed to install plumbing and piping for the drain. If you have any choice, do not design the stream so that the stream bed needs to be pierced anywhere for any reason. There is likely to be enough trouble with unintended leaks without adding any of your own. If you must end the stream on stage, the most common method, of course is in a small pool. If possible design the pool with one 6″ section of the rim lower than the rest. Then, like a gutter drain in a swimming pool, run your piping to the holding tank under the brush, grass, rocks, platforms, etc. Again, avoid having to put a hole in the stream bed liner if possible. If you must place a drain or hole in your stream bead the best method is to use two bolt on, 8″, PVC pipe flanges.

Purchase some 1/16″ neoprene gasket rubber and cut two discs, slightly larger than the pipe flange bases. Next cut an inside diameter hole slightly smaller than the I.D. of the pipe flanges. Finally cut out holes for the bolts. Using one of the flanges for a pattern, cut the stream bed material for the bolt and center holes. Place the flanges face to face on opposite sides of the stream bed with the gaskets in between the flanges and the stream bed lining. Cover both sides of the gaskets with silicone caulk (it will get a bit messy) making sure to surround the bolt holes and the center hole completely with no breaks. Bolt the flanges together carefully and tighten down in a star pattern. Allow this to set at least over night, 24 hours is better, before subjecting it to water. Now add your plumbing from the outside flange to the holding tank. Now for waterfalls. Water falls are really easy, they are just a stream that has a sudden drop. Everything we have discussed up to now apples to waterfalls also.

A waterfall is usually a combination of streams, pools and a waterfall. The main addition is that there will be a constant sound of water as it fall into the pool. Whether this means micing the actors, living with the sound as part of the ambient sound design, placing the water as far upstage as possible or what is up to you. One way to lessen the sound is to have the water hit a steeply slopped surface that then runs down into the pool at the bottom rather than have the water fall directly in to the pool. Making the pool shallow or having something soft in the pool for the water to fall on does not work. In addition to the noise, there is the spatter problem. All surfaces anywhere near the waterfall must be sealed within in inch of their lives or be made of a material that will quickly and easily air dry on their own without soaking the surface underneath. Anything less is to risk mildew, mold, fungus, bacteria and all the bad things that can come with them. To make a waterfall seem more impressive doesn’t take a great deal of water. Simply make the area where the water falls over the edge as flat and long as possible so that you have a very wide but thin curtain of water.

To increase the “size” of the water fall you can also hang a curtain of thin clear or silver strips behind the water(Rosco Glame) and light the water from the side or slightly from the back. If you have access to lights designed for outdoor pool use, light from directly below the waterfall shooting up the cascade can be very effective. What kind of pump should one use and how big should it be? The easiest to acquire are the submersible sump pumps available from any home improvement store, Grangers, McMaster Carr, etc. These are usually fractional horse power pumps ranging from 1/4 to 1/2 horse and from 1400 to 4200 gallons per hour and from $40 to $400. Which one you choose depends on your budget and the design perimeters of you situation. Generally it is a good idea to use the largest pump your budget allows without overkill. It is easy to restrict the flow with a ball or gate valve, it is impossible to get a pump to push more water than its rating. It is often more economical to use two smaller pumps rather than one larger one. In addition this gives you a bit of a safety margin. If one pump fails, you still have water, not as much, but some.

When using any kind of “natural” water effects, there is a great temptation to have the grass and other things run down to and in the water. Be very careful what and how you do this as there is the chance of a wicking effect pulling the water up and away. This can lead to a soaking of areas around the stream or pool and, in effect, a slow leak. The last bit of advice is to build your effect with access to as much of the stream or pool bed as possible, so that leaks may be spotted and repaired as easily as possible, without having to tear up half your set to find and fix them. As the needs and design of water effects are so varied, this discussion has intentionally been very general, with little attention to specific details. If you are actually doing a water effect and have specific questions, please feel free to contact me and I will be happy to offer what help and advice as I can. So, until next month, stay safe, don’t sweat the small stuff…..and remember….it’s all small stuff. —

Michael Powers is the Technical Director at The Meadow Brook Theatre, a LORT B theatre in Rochester, Michigan, a Detroit suburb. Prior to The Meadow Brook Theatre, Michael has worked at such theatres as Geva in Rochester, N.Y., The Lyric Theatre in Oklahoma City, The Cherry County Playhouse in Traverse City Michigan, The Walnut St. Theatre in Philadelphia, The Pittsburgh Public Theatre in Pittsburgh and Wild Wood Park For the Performing Arts in Little Rock.


Categories
SFX EFX

General Wet Stuff

Probably the most common water FX asked for or required by scripts and directors is a sink, usually a kitchen sink. For a sink, supply and storage are virtually the same thing and delivery is often combined here as well. Recovery is usually, but not always, a five gallon bucket under the sink drain. Control is basically making all your plumbing connections and joints water tight with no leaks. Water quality is very important as water from a sink is often consumed. However, as the performer is not immersed in the water, heating it is rarely necessary. Delivery, while usually simple is the biggest variable. The three most common forms of delivery to a sink are: 1. A hose from a backstage faucet or sink. 2. A barrel or container higher than the sink using gravity for the delivery pressure. 3. A hudson sprayer or similar, with the wand removed, hooked to the sink

Other less common methods include: 4. A pressured water tank with a connection to a separate air tank or compressor for the delivery pressure. 5. A commercially manufactured Precharged Diaphragm water tank. When installing a sink on your set, the first thing to do is to adapt the faucet inputs to the type of plumbing you intend to use. This step is the same for all methods of water delivery. The most common and the easiest to use is the common garden hose type of fittings. In the laundry plumbing section of most hardware stores there is a shelf of various fittings to adapt different types of pipe fittings to hose fittings. The fittings on the sink you have will determine just which adapters you will need. Once the sink has been fitted with adapters the next thing to attach is a “Y” hose which is just what it sounds like, a “Y” shaped section of hose with fittings at all three ends.

The “Y” hose is kind of like a two-fer for water, it splits up your water and sends it to both the hot and cold faucets on your sink. From the “Y” hose you then can run a hose to your source of water. Of the first three methods of supplying water, the hose to a back stage sink is by far the easiest. The water is supplied clean and under city pressure. It doesn’t need to be treated or filtered. The draw back to this method is that if there is a leak, the supply of water is unlimited. If the hose runs where it is out of sight, quite a bit of water can run out before anyone discovers the leak. It also means that, unless you can run a second hose to the back stage sink supplying the water, your supply may exceed your drain container. It can be very disconcerting to have the actor turn on the faucet and have water start running out from under the sink cabinet. In addition there are times when the set is in the round, on a turntable or a rolling wagon or some other configuration that prevents you from running a hose to the sink.

The second method, a container that drains to the sink is also very easy to do. The container is simply placed on a platform, backstage landing etc. that is at least six to eight feet or more, higher than the sink . The container holding the water can be a 55 gallon barrel or a 5 gallon pail. The main thing is that it must be very clean. If the container is washed and refilled every day, treating the water is unnecessary. Otherwise it should be treated for purity, much as you would treat drinking water on a camping trip. Purification tablets are available at any good sporting goods store. Because stages are notoriously dusty and dirty, because stagehands and electricians working over head can always knock down dirt, spike tape, snow from last year’s Christmas Carol or Nutcracker etc., any container should always be covered. The advantages of the gravity feed are simplicity in plumbing, limited water supply in case of a leak and it is very inexpensive. The easiest way to run the water from the container to the faucet is simply siphon it. Of course you will need to clamp or fasten the hose in some way to keep the end at the bottom of the supply container.

If the water is consumed in quantity, I suggest acquiring a “potable water” hose from a RV dealer. Some hardware stores will carry this type of hose but not many. The potable water hose is not a necessity for a short run or when the water is used for washing or a small sip, but it will make the water taste a bit better. Otherwise a ordinary, clean, garden hose or laundry hose will do fine. If you want to drill a hole in or near the bottom of the container and install a hose bib or faucet, that is fine and does allow you to shut off the water from the off stage side if needed. PVC valves are easy to work with and can be purchased at almost any hardware store today. Brass or copper valves cost more if you buy them new, are more difficult to work with but are far sturdier in any situation where physical abuse or contact takes place. Iron valves work, are cheap, but they will rust and put a distinct metallic taste in the water. If you have never done plumbing work or don’t have someone available who has, I would not suggest this variation. If you want to try it anyway, a few hints are in order. First, use plenty of teflon plumbers tape on any pipe thread joints.

Second, While I do advise using pliers or channel locks on hose fittings, remember that too tight will produce a leak almost as often as too loose, for this purpose, hand tight and just a tad more is what you are aiming for. Third, all hose fittings require a washer, I prefer rubber but the plastic or other types supplied with hoses are just fine. Fourth, tape of any kind or silicone caulk and similar sealants will never stop a leak when placed on the outside of a hose, joint or tank. Another way to install a valve between the tank and the sink is to get a ball gate valve. It will have pipe threads at each end and a lever type handle. When it is turned 90 degrees it is full open or full closed. These are available from Grangers, McMasters & Carr et al. and better hardware stores. You will have to find adapters to change from the hose threads to pipe threads and back again, but it will allow you to shut off the water from back stage. The major disadvantage of the gravity feed system is that water is HEAVY!

Any platform built to hold a water container must be very sturdy. Any slight bump can start the water sloshing from side to side and if the platform or container are not stiff and sturdy, the result can be a disaster. Water weighs 8.322 pounds a gallon, 41 pounds for five gallons, and 458 pounds for a 55 gallon barrel. The third method of providing water to a sink is the altered Hudson sprayer. By “Hudson Sprayer” I am referring to any of the hand pump type of garden sprayers available at hardware/lawn and garden stores, Hudson and Chapin are two of the best brand names, but any of them will do the job. To use one of these units you must first remove the wand and valve or cut the hose near them. This will give you a rubber/plastic tube about 1/4″ to 5/16″ inside diameter. Insert a hose barb into the end of the tube and secure with a hose clamp. (illustration #3) Hose barbs come in a variety of sizes and styles. The barb section must fit the inside diameter of the hose from the sprayer you are using and the thread end should be male hose threads to fit a standard garden hose fitting. Once you have the sprayer hooked up to the back of the sink, simply fill it with water to the fill line, put the top on and pump till the desired pressure is reached.

The advantage of the sprayer method is that it is easy, cheap, self contained and has a good pressure. The disadvantages are that the volume of water is limited, the largest sprayers hold 2 gallons or less of liquid, and the pressure drops off rapidly the water is used up. If your needs are more complex, you may want to resort to more complex methods of providing water. The most usual reasons for needing “other” methods of producing water are turntables, cut-a-way sets and theatre in-the-round or extended thrust. In all of these situations, a hidden, self contained unit it needed. If the amount of water necessary is small, the hudson sprayer is an excellent method. For situations requiring more water or sustained pressure the two methods mentioned earlier are very good. The first, a water tank and an air tank, is especially suited to a situation where your space is oddly shaped or very limited. In fact, I am using this method on our stage at this very moment. The show is “Having Our Say” and is done on a turntable with a cut-a-way set.

They actually cook a meal on stage so all but two of the cabinets must open and be used, and they use 4.5 gallons of water. The two cabinets that do not open are used for the waste water so the only place left is the space between the walls of the two sets. The available space is 10 1/8″ wide. The solution was to make two tanks out of PVC. One for water and one for air. The PVC used is schedule 40, rated at 260 psi at 180 degrees fahrenheit temperature. When using PVC for a pressurized system, all fittings and joints must be made at a professional level, anything less will leak air or water. For the system I am using now, the water tank is 6″ i.d. at 48″ long, which contains slightly over 5 gallons of water. The PVC fittings needed to build the tank have an outside diameter of 8.5″ so 6″ i.d. is the largest pipe that would fit inside the walls of this set. The tank is constructed with an end cap at the bottom with a hose bib faucet installed in the end cap. To install the hose bib, the end cap was drilled to 45/64″ and tapped to 1/2″ FPT.

Even though teflon tape is not required for this joint, I strongly recommend it as it prevents the possibility of the threads spalling or cracking if you have to remove the faucet in re-insert it for any reason. At the other end of the PVC pipe, a 6″ slip fit socket to female pipe thread adapter was attached. The cap was then constructed from a 6″ male pipe thread to slip fit socket attached to a series of bushings, adapters ending in a shutoff valve and a female hose fitting. Just below the top of the tank there holes drilled and tapped for a pressure gauge, air input and a bleeder valve. (illustration #4) The reason for the 6″ thread and socket adapters is so the water tank can be opened up and cleaned before and between uses. This is very important as a closed tank will grow a forest of mold and bacteria in the months or years between shows that need a sink. The air tank is simply a 4″ section of schedule 40 PVC 4’ long with end caps at each end and drilled and tapped for an air input and a tank pressure gauge. To complete the system simply install an air in put valve, a “TEE” fitting a regulator and a hose to the sink. (illustration #5) The main advantage of the twin tank method is that you can design the tank size and shape to suit very unusual situations.

The last method I will touch on is the use of an accumulator tank. An accumulator tank is a device used in residential water well systems. Check out your Granger catalog under precharged water tanks, a 2.1 gal tank is part # 3P676. Basically an accumulator tank is a two part tank with a rubber diaphragm dividing it into halves. A precharged tank has one section of the tank pressurized and sealed. When you fill the other half of the tank with water under pressure, it further compresses the air in the first chamber. The valves are closed and the water source removed. Then when you release the water into the sink, the diaphragm section provides the water pressure. In some ways it is like the hudson sprayer method except that you don’t have to pump it up. In some ways it is like the twin tank method except everything is in one container. Some of the advantages are that the water supply can be quite large, these tanks come in capacities to from 2 gallons to over 300 gallons. The cost ranges from $45 for a 2 gallon tank to $5,600 for a 370 gallon tank. The disadvantages include the shape and size. They closely resemble a large compressor tank of a comparable volume, basically short, squat cylinders. Another disadvantage is that they are designed to be always filled with water. In the theatre we will use the tank for a few weeks and then it will be in storage for weeks, months or years between uses. Even if it is cleaned with bleach and dried very thoroughly, the probability of mold or fungus etc. growing inside during the storage period is quite high. — 

Michael Powers is the Technical Director at The Meadow Brook Theatre, a LORT B theatre in Rochester, Michigan, a Detroit suburb. Prior to The Meadow Brook Theatre, Michael has worked at such theatres as Geva in Rochester, N.Y., The Lyric Theatre in Oklahoma City, The Cherry County Playhouse in Traverse City Michigan, The Walnut St. Theatre in Philadelphia, The Pittsburgh Public Theatre in Pittsburgh and Wild Wood Park For the Performing Arts in Little Rock.

Categories
SFX EFX

Rain

Michael Powers has graciously allowed us to reprint his articles on the tech site. We are working on bringing in more of Michael’s very informative articles. As for this article, pictures will be added soon

TECHIE’S CORNER Hello! Welcome to the Techie’s Corner. As I said last month, this column will cover as wide a variety of topics as possible in no particular order. If any of you readers wish to suggest a topic, I will be happy to give it a try. Bear in mind that I am notoriously weak in the areas of sound design and reinforcement. This month’s topic is RAIN. Rain on stage, real water, wet, sloppy, leaky, runny water! From a small drizzle outside a window to a real downpour. How do you get the water on the stage and more important, how do you get rid of it. When you make rain on stage there are 6 major areas of consideration. Supply, storage, delivery, recovery, control, and water quality. As you will see from reading, several of these areas overlap or become the same in different methods of creating rain on stage. First we will look at these 6 main areas and try to define and explain them, then I will follow up with a few examples of how you might create rain for a few specific situations. The scope of the column is meant to cover effects produced on live stages for a “theatre” audience, not effects for theme parks or large casinos with millions of dollars to spend. Supply: supply is just that, where do you get the water from? What is the most immediate source to the stage? Is it a sink back stage or down the hall? A storage tank like a 55 gallon barrel? If your supply is from city water in some form or another, you have the advantage of a constant pressure source. It is also cheap and easy. On the down side, if there is a leak, there is an unlimited supply of water to feed the flood. A storage tank has to be refilled, treated as necessary, and requires a pump or gravity to get the water to the rain system. On the other hand, any leak is limited by the size of the tank. Delivery: Delivery is how the water gets from the supply to the stage and how is it distributed or spread out, sprayed over the performing area or dripped behind a window. Delivery needs a force to move the water, a “pipeline” get it to where you want and a “rain head” to release the water.

Generally if an effect is to last for more than a few moments a pump or municipal pressure is necessary to provide the force. However, if you only have a single window, say two or three feet wide, a 55 gal. barrel with at least eight to ten feet of height above the window, will keep a slow, steady rain going for five to ten minutes, depending on the size and number of holes in your “rain pipe”. If the rain only needs to be outside a door as someone enters or exits, something as simple as a Hudson sprayer above the door will work. For a full stage effect a tank won’t and city water will rarely, provide the volume of water necessary. This leaves us with a recirculating system and a pump for most sustained rain effects. How big does the pump need to be? A very quick estimate can be made by figuring the total area of opening you will have in your pipes and multiplying by the height of your rain pipe or sprinkler heads above the stage. This will give you the approximate volume of water you need per second. If you figured in inches, multiply by 1728 to get the cubic feet of water. Now multiply the cubic feet of water you need by 7.481 to get the gallons. Now multiply by 3600 to get the gallons per hour (GPH) needed. The reason for finding the GPM is that most pumps are rated by gallons per hour at a specific “head”. “Head”, sometimes called “Static Head”, is the term for the number of feet the pump must lift the water to the discharge point.

For example, if your pump has to lift the water 20’ to pass over an obstruction, but the pipe/hose comes back down to 10’ at your actual rain pipe, your “head” will be only 10’. The reason for this is due to the siphoning action as the pipe hose comes back down over the obstruction. Although this effect is theoretically the same at any height, obviously there is a point where gravity and internal friction in the plumbing system put a maximum on the height you can pump the water over. The pump simply cannot get the water up to the top of the hill to start the siphoning effect. Now that you know the GPH that you need, you can go shopping for the pump(s) that will provide it. A point of importance here, the pump outlet, 1″, 1 1/2″,2″, 2 1/2″ etc. actually determines the final GPH. Your system must maintain that diameter of piping, on the average, to achieve that rating.

For example, if your pump outlet is 2″ diameter, that is 3.14 sq. inches in area. If you have a branch or “Y” in your system, each branch must have at least 1.414″ diameter, or about 1.5″, to maintain the maximum potential GPH flow. If you need more information for sophisticated systems such as water effects at theme parks, flowing rivers and waterfalls etc., that is beyond the scope of today’s column. Control: How do you make the water spray or fall where you want, and once it hits the stage, how do you make it go to your drain or catch tank? How do you keep the water from soaking the stage (or platform) floor and warping or ruining it? How you direct the spray depends on what kind of spray head or water pipe you use. The three general types of spray devices are: shower head types, including fire sprinkler system heads; rain pipes, basically pipe or hose with holes at regular intervals; modified rain pipes with some additional method of directing the water.

For examples of modified rain pipes, see illustrations 1 and 2. Fire system sprinkler heads are designed to spread the water very evenly over an area. They tend to be best for very large spaces, outdoor use and film or video applications. Spray/shower heads can be used pointed either up or down. Pointed up gives a softer, more realistic looking rain, but of course you have to have height above the piping to clear lights, teasers or other scenery. Pointed down will give you a fairly controllable, usually round or oval spray pattern. The round pattern is great in the middle of an area to be rained on but if you have to cut the rain to a sharp, straight line like a shutter cut with lights, it won’t work. Straight lines and tight control generally have to be achieved by rain pipes or modified rain pipes. Rain pipes, like shower heads can be pointed up or down. Again, pointed up gives a better look but sacrifices a bit of control. Pointed down gives better control, but has a tendency to look too regular…..like a pipe with holes drilled in it. Modified rain pipes offer the most precision control but because the control is so tight, it often doesn’t look “real”. Which is best? There is no best, only what works for you in a particular situation. It is simply a matter of what you and the director want the look to be and what constraints the set, stage, budget, time, crew etc. place on your realization of the effect. The second aspect of control is how to channel or direct the water once it hits the stage.

rain.h1

For something as simple as rain falling outside a window, a small trough to catch the water, tilted to a catch basin like a 5 gallon pail with a small recirculating pump in it is all you need. Rain falling outside the door or over a large portion of the stage is a different matter. The floor, whether a platform lid or the actual stage floor, must be covered with a waterproof cover, linoleum, dance flooring, sheet metal et al. Something like gloss painted masonite won’t do unless you have only one dress rehearsal and 2 or 3 performances. Even then you run a major risk of ruining the floor underneath. All seams and joints must be sealed with caulk or vinyl tape or something similar. Clear silicone caulk is a very good sealant, but you cannot paint it. Silicone caulk also comes in a few basic colors. Acrylic painter’s caulk sounds good but will not last more than a few performances. In addition it does not adhere as well as silicone to a variety of different materials. Basically you need a surface that is completely water tight everywhere except where you want it to drain. The floor must be raked toward your drains and the edges must be either raised like a curb.

 1

The outside pipe was 4″ schedule 40 PVC. There was a slit 1/4″ wide along the entire length. The slit was at the bottom of the pipe and a 4″ strip of screen wire was inserted into the slot. The screen wire was “frayed” three or four wires along the lower edge and snipped or “pinked” to a ragged edge. The inside 3/4″ tube was drilled 1/8″ on 3″ centers, aimed straight up and connected to the supply line. The water sprayed up inside the outer tube and ran out the slit at the bottom. The slit controlled where the water fell and the screen wire broke up the “sheet” effect back into droplets. In the center of the stage I used the same basic method except I cut away ¾ of the outer pipe (illustration 2).

  

This created a shallow curved trough, over the pipe with the spray holes drilled in it. The spray went up and the curved trough spread the water in all directions. But no water went above the pipe system. This was important as there were lighting instruments as close as 6″ to the side and above the piping. The reason I didn’t simply one small pipe with holes drilled in the bottom is that it would look more like a lawn sprinkler with a steady stream of water, not droplets, coming from each individual hole, it looks very regular and fake. If you have at least 20′ above the stage you can do it that way as the steady stream starts breaking up into drops by then. If you noticed earlier, I used two pumps to deliver the water and two pumps to return it, why? Simple redundancy, if one pump failed, I would still have rain, maybe not as much but still rain. I also ran one delivery and one recovery pump on the same breaker. That way if a recovery pump failed a delivery pump would also shut down and maintain balance in the system. You may have noticed that the recovery pumps were half the size of the delivery pumps. Why didn’t the delivery pumps empty out the barrel faster than the recovery pumps could put the water back? The answer is GPM at a specific head. The delivery pumps had to lift the water about 15’ to clear HVAC ducts etc. in the ceiling before arriving at the rain pipes.

rain.h2

The recovery pumps only had to lift the water 36″ to return to the tank. The 1/4 horse pumps were rated at 2750 GPH at 3’ head and the delivery pumps were rated at 2800 GPH at 15’ head, almost equal. The way I controlled the water was to install a shallow rake on the stage under the area where the rain was to fall. I rose only 1″ in 20′ but it was enough to make the water run down stage. The stage was covered with Marley floor and all the seams were vinyl taped. Another method is to make a raised stage with a steel grate floor and a catch basin under it. In my case, the height restriction made any added elevation undesirable. As a result I had to attach the catch basin to the front edge of the stage. The catch basin was a 1′ wide trough across the front of the stage. It was 6″ deep at each end and 11″ deep at the center. The covering for the catch basin was a steel grate similar to that used on fire escapes and catwalks. The rain along the front of the stage fell directly into the catch basin and so there was very little spatter on the audience only 18″ away from a downpour. At the sides of the thrust stage there was a street curb 6″ high and 18″ wide. It channeled the water down stage to the catch basin. The rainfall on the sides was directed to fall just inside the curb so that it blocked the spatter on the patron to the sides This has been a rather basic over view of what needs to be considered when putting rain on stage. I hope I have covered your questions and given you enough information to start out on your own.

Michael Powers was the Technical Director at The Meadow Brook Theatre, a LORT B theatre in Rochester, Michigan, a Detroit suburb. Prior to The Meadow Brook Theatre, Michael has worked at such theatres as Geva in Rochester, N.Y., The Lyric Theatre in Oklahoma City, The Cherry County Playhouse in Traverse City Michigan, The Walnut St. Theatre in Philadelphia, The Pittsburgh Public Theatre in Pittsburgh and Wild Wood Park For the Performing Arts in Little Rock.

Categories
SFX EFX

Fire part IV

Another type of torch was the “bundle” type.  This type of torch consisted of a number of thin twigs, reeds, plant stalks, whatever bound together tightly.  Again, the business end was soaked in some type of flammable substance.

The main point of soaking the burning portion of the torch in something flammable was to prolong the burning time of the torch.  Soaking the torch produced an effect like a candle or kerosene lamp with the torch becoming the “wick” and the absorbed substance the fuel. In this manner the shaft of the torch didn’t burn, only the “wick” and “fuel” which could be renewed.  Some very elaborate torches had hollow shafts and in fact were much more like oil lamps than what we think of today as “torches”.

Just what the torches looked like then and what they are supposed to represent now is a matter of research for the designer, our job is to make it look like it is burning.  One of the easiest methods is the old flashlight trick.  It works best in a crowd scene, far up stage, on a large stage.  To be perfectly honest, this method is not very realistic and works best when either realism is not the goal or in a large moving crowd scene where there are many other distractions.  To make this effect is simple; it is just a normal flashlight with some gel (color media) and a bit of dressing to cover up the modern flashlight.  The gel is cut into flame like strips and taped together in a series of concentric circles.

fire411After the gel strips have been cut, lay them out flat and get artistic! Use transparent markers to draw "“flame” lines and add various colors to the individual areas of flame.  Another way to add to the look is to cut individual flames from various colors of gel and tape them to the larger strips.  Next, tape the large strips into a circle or ring. Now use hot glue, starting with the center or inner ring; attach directly to the flashlight lens. The final step is to dress the flashlight body to look like the kind of torch handle you need.  This can mean wrapping in burlap and adding cord bands. It can also be done by cutting some long, narrow triangles of 1/8” ply or mat board. The wide end of the triangle should be about ½” to 1” wide. The narrow end about ¾ as wide as the top. The length of the triangle should be several inches longer than the flashlight. 

Another torch that works rather well is a variation of the silk flame trick. 

This one requires a bit more work and a few more parts. I am going to list the parts with Allied Electronics part #s because even if there is no Allied Electronics near you, you can look at their on line catalog @ www.allied.avnet.com (SITE IS DOWN as of 4/6/02)  to see the item. That will allow you to locate similar or equal items from a supplier in your area. The parts are as follows:

1. A small muffin type fan like those used to cool electronic equipment. 4” to 6” (102 mm to 153mm) in diameter depending on your torch design. The Fan should be 12 volt DC brushless fan with a high CFM (Cubic Feet per Minute) ratting. An example is Allied Electronics stock # 599-0660. For those readers using the metric system, there are roughly 35.5 cubic feet in a cubic meter, if I have done my math correctly.

2. Battery (s) to match the fan chosen. Standard D cells will work fine but you need 8 to get 12 volts for your fan. I prefer a small electronic sealed lead acid type. They come in sizes as small as a pack of cigarettes and can be recharged. A good example is Allied Electronics stock # 621-1208 with charger # 621-6310. This battery is 3.78” x .96” x 2.42” (96 mm x 25 mm x 62 mm)

3. 12 volt automotive tail light or turn signal lamp and a socket for the lamp.

4.  A small bit of colored china silk or similar very light weight fabric.

5. Misc. wiring, a switch, connectors etc.

6. Decoration.

fire4

 

The Flame part is rather similar to the flashlight gimmick. The difference is that there are usually only two rows of flame and the outer one is the silk fabric. The silk strip should look similar to either the outer or middle ring of the gel strips shown above and should run roughly along the centerline of the airflow. That is, if the fan blade is 4” in diameter and has a solid 2” diameter center, the silk strip should make a 3” diameter circle. The flame sits directly on the center of the fan, and depending on the design of the fan, may need a wire frame of something to hold it up off the rotating center of the fan. The wiring runs around the fan and down to the battery and switch.

As with other silk flame effects, the look can be enhanced by artistic “painting” on the silk with brightly colored dyes. Do Not use paint, as it will make the fabric too stiff. Also, as with other silk flame effects, there are very few absolutes and a lot of trial and error. Plan to spend some time experimenting with several fans for power and noise, and some time cutting the fabric to look and act the way you want.

fire41

The next item on the agenda is candles. Candles are an enigma. Fake candles rarely look realistic, even the best of the commercially made units. On the other hand, real candles drip, sometimes smoke, can be distracting because of the flicker and often it is a problem to keep lit if an actor has to move about the stage with the candle.

 There are a number of very good commercially made units, the two I am most familiar with are the Rosco candle, available from almost any theatrical dealer, the Candlelite unit from City Theatrical and many special effects and magic dealers have their own house brand. Most of the commercial units are between $35 and $50 U.S. to purchase. The best units have three or four lamps, one to maintain a steady background glow and the others to “flicker”. These candles run off a single 9V battery or with a power adapter that you can plug into a wall outlet. I do not know if the adapter version is available where the standard voltage is 220 VAC rather than 115. I have never tried to “dim” one of the commercial units so I don’t know if that will work or not. The Commercial candles also come with or without a white plastic tube with “wax” dripping down the side a bit. These candles look best where there are several such as a chandelier or candelabra and the candle gimmick becomes part of the background rather than the point of interest. They look the worst when there is only one candle on stage because all the audience attention is drawn to the one fake candle.

1. 555 timer chip

2. R1 1K ohm, ½ watt, 5% tolerance.

3. R2 1.8 Meg ohm ½ watt, 5% tolerance.

4. A small PC board 1” x ½” or a kit to make your own.

5. D1 almost any diode will do.

6. C1  4.7 mf 

7. C2  47 mf

8. 2 Micro lamps (grain of rice) 12 volts, 60 ma.

9. DPST switch

10. Misc. wire, solder, flux etc as needed.

 The last section this month is on Lanterns. Lanterns are the simplest of all as you can simply take any of the methods used for candles and place them inside a prop lantern.

fire42

The largest single problem when dealing with torches, candles and lanterns on a live stage is the same whether one is using real or fake flames, is turning them on or off with the rest of the stage lighting. There are a number of ways of dealing with this. Some methods are commercial units that interface with today’s computer consoles and are somewhat expensive. There are a number of shop built methods that work in varying degrees and are reasonably affordable. However they require a bit of knowledge of electronics and circuit building and each individual circuit is an article in and of itself. Some of these circuits will be the basis of a future article. 

 In the meantime, remember, if any reader has any questions concerning this article; feel free to contact me. As with all other articles, when this moves to archives, the illustrations will no longer be supported. If you are reading this in the archives and would like the illustrations, let me know and I will send them to you.

 As always, don’t sweat the small stuff……and remember……it’s all small stuff.

Categories
SFX EFX

Fire part III

Theatre has always thrived on some form of spectacle. Special effects have been with us since the time of the Greeks. Buildings on fire, volcanoes erupting and explosions are all exciting events on stage. But how do you do it safely and night after night? This month we will look at one of the oldest and simplest forms of fake fire, the silk streamer and blower method. The most recent time I have seen this method use was in the ice capades where a small wall of flames rose suddenly behind the skaters for a few moments and then disappeared with no trace of smoke or heat. The lack of smoke can be an advantage or disadvantage depending on the final desired effect; in this case it was a definite advantage. In an ice show the ability to produce flames without heat is an obvious advantage. Of course the silk streamer method does not need the approval of the fire martial which is always a plus.

Simply stated, the “flames” are strips of some very light weight but tightly woven cloth, cut into strips or a series of strips to resemble flame shapes. The thing that makes the flames look the most realistic is the color or “dye job". A good color job on fabric flames is a variegated blend of color from the base to the tip and from flame to flame. Real flames tend to be a deeper red-orange color at the base and more light orange or yellow toward the tip. Occasional flecks of blue and green can add additional reality to the look of a flame.

fire37

Until the middle of the 20thcentury, silk was the fabric of choice as it was very light weight, tightly woven and would easily take bright colors of dye. Silk also had a shimmer or sheen that would reflect light very effectively. Now there are a number of synthetic fabrics that can be used. Rayon, nylon and polyesters galore are available. How long should the strips be? How many should there be? The length of the strips is determined by the desired look and the strength of the fan or blower you have available. The most common length I have seen or used is between 10” and 24”.Less than 10” is hardly effective and with strips longer than two feet it is very difficult to prevent tangling. The number of strips is again, determined by the desired look. Generally two or three look the most realistic, but even a single row can look great when lit well.

fire38

Silk strips are nothing without some form of air movement to raise and flutter the streamers. Some of the methods used by our forbearers are at once, primitive, ingenious and incredible. One method used by early church pageants and miracle plays was the “Bellows” method. In this method, a large bag of leather was fitted with a number of bellows or manual “air pumps” with one way valves. The “air pumps” were operated by many means such as hand pumps similar to today’s fireplace bellows, or by foot pumps like those found in old pump organs, or giant fireplace bellows operated by a water wheel. By this means air could be pumped into the bag from the bellows, but could only escape by blowing past the silk streamers. The leather bag was then compressed by weights or simply by a person sitting on it! Much like a bagpipe, it then produced a steady flow of air rather than a series of “puffs". Today a chamber such as the leather bag is known as a plenum chamber.

Today the airflow is provided almost exclusively by electric fans or blowers. Fans with a propeller type blade are a poor choice for this effect as they produce an air current that looks like the double helix of a DNA molecule. This has a pronounced tendency to twist and tangle the streamers. Fans or blowers known as squirrel cage fans are a far better choice. First the airflow is in a straight linear column. Second the squirrel cage type of fan produces a greater “force” known as static pressure. Static pressure produces greater “push” against the fabric streamers for the same or less air velocity and noise as propeller type fans. Squirrel cage fans are also known in the air moving industry as “centrifugal blowers". There are three types of blowers named by the shape of the blades or fins that make up the fan. They are: the Forward Curve (FC), the Backward Incline (BI) and the Radial Blade (RB).

fire39The forward curve is the most common and the one you are most likely to encounter. The FC blower is the quietest and produces the greatest airflow for the noise level. The BI and RB type blade blowers produce, respectively, increasingly greater air flow and noise levels.

So, for example, a quiet, romantic fireplace would probably need an FC type of blower. A large flame coming from a burning building window with crowd noise and sirens might ask for a BI type. Flames spouting from a distant volcano or a boiler explosion might need the extreme airflow of an RB blower.

For the most part, 90% of the blowers the average consumer is going to encounter is the forward curve type. For fireplace or a windowsill, a wide narrow blower is needed such as those offered by Grainger as Tran flow or low profile blowers. These blowers run from $45 to $95 and are listed in the 4C743 and 4C825 series. Other suppliers such as McMaster-Carr et al have many similar blowers.

The final thing that makes this fire effect work is the lighting. To be perfectly honest I cannot find, nor imagine a good, safe, way to light fabric flames without electric light sources. Today we have a number of very bright, sources of light such as the MR-16 type lamps. These are very small and can be concealed rather easily.

fire310

While I have shown MR-16 lamps in the sketch, any type of lamp that you can use will work to a greater or lesser degree. I should mention here that the lamps should always be aimed so that when the fans are off, the light is not aimed at the fabric. Otherwise the fabric without the air cooling effect can catch fire very rapidly.

The descriptions and illustrations of the fire effect may seem a bit vague so far. That is true. The reason is that this effect is very much a trial and error type of thing. The exact fabric you choose, the particular “look” of the fire, whether a campfire, or a fireplace etc, the space you have for lamps, the size and shape of the air holes, etc will all affect the exact operation of the effect. It is a rather easy and surprisingly realistic way to produce fire on stage but it does take a bit of work to get it the way you want.

As with all the tech tips I write about, if you want to give them a try and need some help, feel free to contact me.

Until next month, Don’t sweat the small stuff, and remember …. It’s all small stuff! 

Michael Powers

 

 

Categories
SFX EFX

Fire part II

The starter is the main ingredient in the mix. Starters are the small silver cylinders about

1 ½” long and about ¾” around that fits into one end of older type fluorescent fixtures. They are available at most home improvement stores, hardware stores, Home Quarters, Home Depot et. al. A starter is basically an electrical capacitor that gives a short boost of voltage to start the old style (slow start) type of fluorescent lamps and then turns off. In a fluorescent fixture the starter is then out of the circuit until the switch is turned off and then on again. In our effect, the starter is wired in series with the lamp and is “in the circuit” all the time. When the switch is turned on, the starter is “off” but it starts storing up voltage. At a certain point the voltage builds up and “overflows” causing the lamp to light up. The starter is now “empty” of electricity and “shuts off” causing the lamp to be dark. It is kind of like a bucket under a faucet that is hinged to tip over when the bucket is full and to tip back up when it is empty. In the fluorescent fixture the starter only operates once each time the fixture is turned on, therefore it is not important just how consistent or accurate the starter is. The impreciseness helps in our circuit because no two lamps will blink at the same rate.

 For most fire effects, at least three or four lamps should flicker and one should be on for a steady background effect. If physical space in your fire unit permits, as many as nine or ten lamps may be used. As you increase the number of lamps you can lower the wattage. However a mix of different wattages makes a more realistic effect.

 To wire your effect you will need a starter for each lamp, a socket for each lamp, a male Edison plug, wire, wire nuts, a plywood (or similar) base. You may wire a switch into the circuit or design the wiring to plug into a switch box that you already have on hand. The most critical part of the wiring is the starter. There are two small prongs on one end, most look like the head of a nail that is sticking out about ¼”.The starter should be fastened down in some way, hot glue, plumber’s strap, heavy rubber band, Velcro strap etc.The wiring must not contact the outer case of the starter in any way. The easiest way to connect to the starter is to use small, insulated alligator clips available at Radio Shack. This makes changing the starter very easy if necessary. You can also solder directly to the contacts. The wiring is fairly simple as shown in the illustration below.

fire25

fire26

To add color, refer to last month’s article for a complete description of using gel (color media, Lee, Rosco, GAM etc.) to enhance the effect.

 Next month I will be on vacation, but in August’s column we will take a look at the centuries old but still effective, “Silk Streamer Fire Effect". Hope you enjoy the articles, have a nice summer.

Don’t sweat the small stuff and remember…….it’s all small stuff!

Categories
SFX EFX

Fire on Stage

How does the “mood” of the fire affect how we build/create it? First, do we need visible flames or just an indirect flickering glow. Is the color of the fire a warm glow or a cold heat? The more you use reds/orange, oranges and yellows in the flame the more it will seem hot, searing, arid. Colors in the amber, rose and burgundy range tend toward the “romantic". Flames that are white hot, blue-white and blue tend to give the audience a feeling of unease, of very intense heat or strangely enough of a cold heat. Green flashes can give a softening effect to the red range and add an eerie unworldly effect when used as the main color or mixed with the white and blue-white flames. 

For what it is worth, real flames tend to have some of all these colors in them, the balance depending on how much oxygen is present and the exact composition of the fuel. But we really don’t care what the actual chemical composition of the “fuel” would be. Verisimilitude here is secondary to creating the right mood.

Now that we have briefly discussed what fire should be or do, we will move into some basic methods of creating it. This month’s method will be a small battery operated fire unit that can be used in a trash can or behind or under logs to simulate a wood fire. In addition it can be used in conjunction with some of the methods I will touch on in the coming months.

The fire unit for this month consists of a few simple basic elements; several 12 volt lamps between 20 and 50 watts; a 12 volt battery, power supply or transformer; wire; terminal strips or buss bars; sockets; automobile turn signal flashers and one 20 amp toggle switch.

Lamps can be any 12 volt lamps you can locate. Light bulbs from motor homes, campers and other RV’s that look like a normal, house hold light bulb, medium screw base “A” lamps, but designed to operate on 12 volts DC are one type. These can be purchased at Wall-mart, Motor Home/RV dealers, most KOA campgrounds and other placers that cater to the RV camper trade. Automobile tail light lamps or halogen head light lamps are anther very good type of lamp to use. Headlight lamps are brighter than tail light lamps. These can be purchased at any auto supply store, K-mart super stores, Wal-mart etc. Twelve volt MR-16’s can also be used. The MR-16 looks like a small reflector lamp about 2” across the face and come in many types from 6 volts to 12, 24, 82, 120, 220 and other various voltage designs, which means you have to double check the voltage before you buy them.MR-16 lamps can be purchased through Grainger, McMaster Carr, Newark Electronics, Allied Electronics and most electrical supply stores and lighting stores. Which type of lamp to use depends on availability in your area, cost, and physically how large you need your completed unit to be. In general the RV lamp creates the largest fire unit and auto lamp units the smallest.

Sockets: sockets can be any kind that fit the lamps you intend to use, or one can solder leads directly to the lamp contacts or base. If sockets are available, I strongly advise that you use them as this makes replacing a lamp much easier and the socket can be firmly attached to whatever you use as a base for the fire unit. 

Wire should be at least 16ga stranded from the lamps to the flashers and from the flashers to a common buss bar or terminal strip. The single wire from the terminal strips to the switch and from the switch to the battery must be 12ga minimum. The reason the switch must be rated at 20 amps and the power leads to and from the battery must be at least 12 ga. is that the amperage in the system is a lot more than you may think if you are not familiar with low voltage circuits. Usually the best lamps for this effect are about 50 watts. Using ohms law, Watts equal the Voltage times the amperage (W=VA) we find that a single 50 watt lamp at 12 volts equals 4.16 amps

( 50 = 12xA; 50/12 = A; 4.166=A). A 25 watt lamp would pull 2.08 amps. I suggest using six to nine lamps for this effect. Lets figure the amperage if all nine lamps happen to be on at the same time. We can multiply 4.16 times nine to get 37.44 amps or we can use the formula W=VA to find that450 watts divided by 12 volts equals 37.5 amps. Either way we are exceeding the capacity of both the switch and the wire. However we can do what electric companies call de-rating. As the flashers are not a precision device, the lamps are going to flash randomly and the probability is that even if all 9 lamps should be on at the same time (very unlikely) that the time duration will be very short. In fact each lamp is only on for about half the time so by averaging that means that the current will actually be about 18 amps at the worst. If you are using lower wattage lamps then you can figure the amperage for your self if you want or you can simply stick with the wire for the 50 watt situation and know that you are O.K. am not sure if standard auto flashers will handle 100 watt lamps as I have never tried it. I feel that this would probably be too bright for most situations. However if you need a very bright effect try 100 watt lamps and perhaps a flasher for a tractor trailer rig. If any readers try this please give me an e-maifire11l and let me know how it works or not.

Now for the power for our effect. If you buy or build a power supply, make sure that it is rated for the 100% of the amperage your effect can generate. Even though we derated the wire and switch because of the flashing effect most power supplies have fast blow fuses or breakers that will pop when their amperage is exceeded even for a very short time. When it comes to batteries, any combination that equals 12 volts will work just fine. The question is for how long. If your effect has to be small and self contained, a series of C or D cells will probably do the trick if the effect doesn’t have to last more than a few minutes. Lantern batteries, the square six volt kind, are another good solution. They will last a bit longer than the C or D cells and will take up little more room. The best battery I have found is a lawn tractor battery. It is a wet cell 12 volt battery that looks like a half size version of your car battery. It is a very powerful power supply in a very small package. It will run a 9 light effect for an hour or more. In addition it is designed to be recharged. A small 12 volt trickle charger can recharge it between shows. The battery costs between $30 and $50 at most discount stores that sell riding mowers and lawn tractors. The charger will run about $25 at auto stores or discount stores like Wal-mart, Home Quarters, K-Mart et al. 

 

Now it is time to actually build our effect. First we have to determine just how the effect is to be used. One problem with the flashers is that they make an audible click as they cycle on and off. Whether or not this sound is objectionable depends on the size of the stage, the type of show (loud musical, quiet drama) and just where on the set the effect is located. When possible it is usually better to build a separate container for the flasher units, sound insulate it and locate it as far away as practical. For an example, see illustration # 1.fire12

An example of a sound isolated box is seen in Illustration #2.Note that the flashers need no air space for operation or cooling so they can be mounted so that they are actually touching or very close.

 

 

  After choosing the lamps and sockets the first step is to lay out a full size circuit pattern on Kraft paper, drafting paper, fire13card board or something similar. If you need to make separate boxes, containers or mounting boards for the lamps and or flasher sections, make your drawing accordingly. As you make this lay out drawing, pay attention to where the contacts are on the various elements so that you don’t make the wiring harder than it should be.You will need a separate flasher for each lamp. This is so that each lamp will flash independently of all the others.

 

Each lamp must be wired in series with it’s flasher, then all the flashers need to be wired in parallel to the switch and power, see illustration # 3.

Note that this illustration is not to scale and indicates the wiring connections only, not necessarily the physical location of any item in the actual construction of the effect. You can also use wire nuts to replace the terminal strips but the number of wires quickly makes this awkward and unwieldy.

Tfire14he flashers can be attached to the plywood by hot glue, epoxy or construction adhesive like liquid nails. When buying the flashers you will notice that some have two contacts and some have three. Both can be used you just have to connect a lamp across any two of the three contacts and move the wires from one contact to another until it works. The third contact is then simply ignored.  

Finally for the fire unit itself, attach the sockets to a piece of plywood, 1/2” or 3/4”.You can space the sockets as close as the lamps and wiring convenience will allow. The plywood base should be 2” or 3” larger than your socket layout to allow ample room to attach color media.T he easiest way to do the color media is to start with a sheet of clear. Next cut small, odd shaped pieces of scrap gel (leftovers from cutting gel for lighting instruments) and scotch tape them to the clear sheet. Any thing from 2” to 6” across is fine and the more irregular in shape and size, the better. Next, wad the sheet up into a tight little ball, then lay it out flat again. At this point you might have to repair your tape job in a few places. In this crumpled state the gel sheet can be shaped into a self supporting “dome” that can then be stapled or taped to the plywood base over the lamps. It is best if there is at least an inch or two between the lamps and the gel. There is no fire danger if the gel touches a lamp, but the effect looks better if each lamp lights up several gel pieces as it flashes. If the gel “dome” will be visible to the audience, a bit of artistic dusting, mostly around the bottom, with flat black spray paint will help to make it look like coals or embers. If the effect is to be in a trash can or other “out-of-sight” location, the crumple and spray can be eliminated. Just place a piece of screen wire or chicken wire over the lamps and lay the gel pieces on top. You still need to tape them together though so that air currents won’t shift the gel away.

When doing the wiring, lay it out in as neat and orderly a manner as possible. Group the wires together and fasten firmly to the base where the bundle of wires goes to the flasher box. If you use nine lamps that means you will have 10 wires going from the lamp unit to the flasher box, nine to the individual flashers and one from the terminal strip to the battery. Use tie wraps, tape or something to create a neat bundle.

In the next few months, I will touch on other methods of creating fire. As always, if you have any questions, feel free to e-mail me and ask. Till next month……Don’t sweat the small stuff and remember……….its all small stuff