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May 4, 2007

Tekes Esh: fire-writing

Gal Longin (who has shared projects with us before) from Israel wrote to me to tell me about an annual Scouting ceremony called 'Tekes Esh' which is Hebrew for 'fire writing'.

Scouts make fire sculptures for this ceremony, using paraffin-soaked cloth 'snakes' attached to a metal grid. The grid is supported by a pioneered frame, with tinfoil insulating the lashings that are closest to the fire. These pictures and words are clear for around 15 minutes of burning, after which parts start burning out, and after 45 minutes the fire is normally out altogether. As Gal mentions, this is a potentially dangerous activity, and it is important to take safety precautions: make sure you have fire extinguishers, keep the fuel far away from the frames when they are burning, and consider informing the fire department of your activity in advance.

Gal has done a series of drawings which explain different techniques that can be used for making these displays, and even animating them, with screens that spin, drop down and change over time. Here then, are Gal's notes (with slight editing from me to include English names of knots and add hyperlinks).

The most basic idea is the static simple one. As you can see I only wrapped with aluminium foil the parts that were close to the fire (letters) and the lashings. You can also see that the 4 ropes holding the window are not directly connected to the window but to a thick metal wire connected to the window so that they would be isolated from the fire.

A more complex yet fairly simple idea is illustrated in the second picture where the writings are divided into two parts (could be more than two) and folded on each other . The two grids are connected on one side with small metal rings from thick wire which acts as a pivot and at the other end they are only connected using a thin burnable rope which has been preferably dipped in oil. Once the letters catch on fire the rope burns and the two grids depart and reveal the message. You could also do this without a burned rope using a highwayman's hitch, so by pulling the right end you untie the knot and release the grids.

Another cool idea is to have a sliding grid. In front of the crowd you have a big window with only part of the sentence/message/symbol and on another window behind it you have the other half. You have several cables connecting the hidden grid and the front window and you slide the grid forward on these cables. You should slide it after it's burning so the visual effect is more impressing.

Another idea is to a have a swinging message. The grid is connected to a strong pivot above. The swinging is quite simple yet very cool and impressing.

Another is idea is to use vertical pivots to rotate the grids.

A more complex idea is the centrifugal one. In this idea you have a big thick pole like a log or a telephone pole or even several thinner poles tied tightly together. The main purpose of this is that the it will have enough mass to stay stable even though great power are exerted on it. Once you have the pole up in the air you secure it to the grounds with ropes and secure it to the ground at it's base with stakes. Around it you create a polygonal shape grid (a triangle is best because it's the strongest shape but if you have diagonals you can also build rectangle and pentagon). if you have a triangle you should use three words and not two as in the drawing. Once the triangle shape is finished(you should try build a wooden frame for each grid to keep it sturdy) you hang it in the air from the top of the poles using three thick ropes. Then you rotate around the pole a few times and you secure it while it's twirled. After you light the sentence you release it and it spins and reveals the message. Make sure you rotate it so that it spins in the right direction (so that people could read "hello big world" instead of "world big hello"), after that it should spins in both directions for a minute or two. Be very careful with this since there are very large and heavy things moving very fast. Keep people away at a safe distance and make sure the main pole is strong and stable.

A different idea is to build a flipping message. You build two rectangles and secure them at a right angle. One rectangle is laying on the ground and the other is secure the common side to the ground. When you light it you light both words, and after a moment or two when the crowd has seen it you pull the ropes and flip it. It's very impressive and cool and usually it's for a message of change, like if the scouts go through something like getting a new rank, you write on one side the old rank and on the other the new one.

Another way to deliver a message of change is to have a rotating grid (ehs7). You write two different words on each side of the grid and make sure there is a thick material between them so that you can't see through it. Basically you just spin it on it's pivot(usually a thick PVC pipe, if you use PVC or any other plastics make sure you wrap it in aluminum foil so that it doesn't melt or anything).

A different creative idea is the falling balls idea (esh8). You place on the grid many many balls (also made from cloth) at a seemingly random order. But it's not really random at all- most of the balls are secured to the grid using a thin rope that will eventually burn so that the ball falls. Only a few balls are secured with a metal wire so they never fall. Once all the fake balls fall they reveal the message in the left balls(in the picture you can see the letter H revealed). It's usually a symbol not a sentence since it's quite difficult to create many letters in that method. but it's very cool since the crowd doesn't know what's the message and it is slowly revealed by the fire.

(illustrations courtesy of Gal Longin. Photographs courtesy of Israeli Scouting at
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