http://www.ghost‐songs.com/props/PropFloater.html#index They say a picture is worth a thousand words, well I am going to give you as many of both as I can! Let us start with a couple pictures of the moving variety in Windows Media (.wmv) format. The first video shows the Floating Candelabra as it appeared during our 2006 Halloween season. As you will see the video camera does not do a particularly good job in the low‐light environment, but it should suffice to convey the smooth, flowing animation of the prop... Gee, perhaps I should have used a tripod... Hah!!! Oh well, live and learn. One of the primary objectives I focused on while developing the Prop Floater was to create an animation that appeared organic and wandering instead of the obvious, repetitive pattern commonly seen when using a Flying Crank Ghost (FCG) type setup to float a candelabra. Please do not misunderstand, I am in no way criticizing the Phantasmechanic's FCG mechanism (or any other similar crank‐type system) for use as a prop floating device; in fact, I suspect that for many haunts the FCG technique will prove to be the better choice. Heck, even Disneyland uses a motorized crank to fly their candelabra in The Haunted Mansion's endless hallway. However, for our haunt, an entirely different kind of animation was needed. I wanted the motion to appear as light and "floaty" as possible; fortunately, I knew just where to turn for inspiration! I have long been a fan of the now deceased Hallowed Haunting Grounds and have always enjoyed a particular fondness for their Floating Ghost Lantern (FGL) which was originally designed by Greg MacLaurin. In its simplest from, the FGL is basically a pair of counterbalanced levers suspended beneath a slowly rotating motor. This arrangement achieves the smooth, irregular motion I wanted to emulate; unfortunately, the FGL animationObtained is limited to the horizontal from with no appreciable vertical movement. I found myself wondering if there was any way to turn the whole thing on its side... Omarshauntedtrail.com How can a 25 gram mouse lift a 5 ton elephant? ~ OR ~ The exciting world of levers, fulcrums, and static equilibrium... A lever is a simple machine consisting of a bar supported at a stationary point along its length which is used to overcome resistance at a second point by application of force at a third point. The stationary point of a lever is known as its fulcrum. Static equilibrium is established in a lever when the sum of the forces acting on one side of the fulcrum multiplied by their distance from the fulcrum is equal to the sum of the forces acting on the opposite side of the fulcrum multiplied by their distance from the fulcrum. As a result, it is possible to counterbalance a very large force at a short distance with a very small force at a great distance. Having the lever in mind, Archimedes is supposed to have boasted that given an appropriate place to stand he could move the world. The above is in a state of static equilibrium with all forces balancing if (F1xD1)=(F2xD2). If we assume our elephant weighs 5 metric tons and is standing at a distance of 10 meters from the fulcrum, then our 25 gram mouse would need to have an exceptionally long lever of 2,000,000 meters (approx. 1,242.74 miles) to achieve a state of static equilibrium. Eeek, indeed! Of course this simplistic example ignores some real‐world complications, not the least of which is the fact that a lever has to be made out of something and therefore contributes the weight of its own mass to either side of the equation... Obtained from ...Which brings me to my next dull‐yet‐mercifully‐brief topic: Momentum. Omarshauntedtrail.com Thanks to Newton's classical Laws of Motion we know that all moving objects have momentum. The amount of momentum an object possesses is equivalent to the product of its mass and velocity, thus the greater the mass of an object the more energy is required to alter its direction of travel. If we set our oh‐ so carefully balanced lever into motion, its momentum must include the mass of the elephant, the mouse, and the lever itself. The greater the mass of the lever, the greater its momentum. By the way, it is theoretically possible for a mouse to have the same momentum as a stampeding elephant! If our elephant friend was moving at a steady 5 kilometers per hour, the mouse would simply need to race along at a zippy 1,000,000 kilometers per hour (or 172.6 miles per second!) to achieve an equivalent momentum. What does this have to do with the Prop Floater? Very little... Its just kinda cool! Hey, what's with all this nonsense about levers, momentum and dead physicists??? As you saw in the Prop Floater video, this device consists of an animated mechanical lever with a candelabra at one end, a fan & motor assembly acting as a counterweight at the opposite end and a pivot point (or fulcrum) near the center. If the lever remains unaffected by other forces, it soon achieves the boringly harmonious state of static equilibrium... But we want this prop to move! The rotating fan, powered by a repeat cycle timer, provides ample force to keep the whole thing animated. It is important to understand that the total weight of the lever including the candelabra, fan & motor assembly as well as the physical lever itself needs to be as light as possible. Because the lever is in motion, a greater total mass will necessarily result in greater momentum and thus increase the difficulty of achieving the desired ghostly animation! The lever in my Prop Floater is made from aluminum tubing and I HIGHLY recommend using aluminum or another similarly strong, rigid and lightweight(!) material to anyone attempting this project. Does the entire Prop Floater need to be made from aluminum as mine is? No. The supporting framework is stationary and can be made from anything you wish, in some situations it may even be eliminated entirely; however, the choice of materials for the animated lever requires special consideration. Alright already, let's get to the nuts & bolts and have ourselves some prop‐building fun! The construction details are divided into the following indexed sections: MECHANICAL LEVER ALUMINUM TUBE The mechanical lever is made from a 72 inch length of 5/8 x .093 round aluminum tube. You may find that you need a lever Obtainedof a different lengthfrom depending on the width of the window or display area in which you intend your prop to float. For the 32 Omarshauntedtrail.cominch opening of my window display this length works quite well. Drill a small hole through the exact center of the aluminum tube and attach a small hook‐eye type bolt secured using a locking nut. The hook‐eye is the pivot point (or fulcrum) of the lever. Eventually you will attach the hook‐eye to the support frame's suspension beam using a heavy‐duty fishing swivel. You may now paint the front half of the lever flat black or cover it with an appropriate length of black Duvetyne tape. I greatly prefer the Duvetyne because it is "flatter" than the paint and does not scratch off. If you are unfamiliar with Duvetyne, you may purchase it through various theatrical supply companies. See the Resources & Suppliers section. Next you will need two lengths of 7/16 inch poplar dowel. The long dowel should be cut to a length of 32 inches, the short dowel should be cut to a length of 8 inches. The dowels should fit quite snugly into the aluminum tube. The long dowel will be used to attach the fan & motor assembly to the counterbalance end of the lever and can simply be set aside for now. The short dowel will be used to attach a prop (in our case a candelabra) to the audience end of the lever and requires a bit more work... Pre‐drill a small hole into the end of the short dowel and screw in a metal cup‐hook. If you find that your cup‐hook is too long you may simply cut, grind & shape the end of the hook using a dremel tool. Give the small dowel and hook a good coat of flat black spray paint and let dry. NOTE: The dowels are held in place within the aluminum tube simply by the snugness of their fitting. The dowels should slide in and out reasonably easily, yet without any extra looseness. If this is not the case, double‐check that you have purchased the correct size aluminum tube and dowel. Also, be sure to avoid accidentally sliding the dowels completely into the aluminum or you may not be able to easily remove them. Seriously, trust me on this one... FAN & MOTOR ASSEMBLY The fan & motor assembly is easily the most complex element of this entire project. It is important that you thoroughly understand how it is intended to work, so before we proceed I recommend that you watch the Prop Floater Video again paying Obtainedparticular attention from to the "Fan & Motor" section... Omarshauntedtrail.com Fan Specs: 12vDC Brushless Fan 0.11A, 1.32W 3200 RPM, 14.5CFM Radio Shack Catalog Number: 273‐239 Motor Specs: 115/120vAC Geared Reduction Timing Motor 3W, 4RPM American Science & Surplus eBay Both of these items may Obtainedrequire a bit of research to track from down. This particular model ofOmarshauntedtrail.com computer fan is frequently unavailable from Radio Shack's online store; however, their physical stores should still carry it.
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