Winter is coming and Christmas school activities are too (Fear both of them).

My little Guiller and his class will sing a fun carol dressed as a kind of 'vintage sheperd'. They need a campfire for the center of the stage and his teacher asked me if I could build one.

Challenge accepted!

It has to be:

Portable
Child-safe
Battery operated
As real as possible

Supplies

* some branches

* some screws

* a piece of plywood

* hot glue sticks

* PVC pipe, or any cylinder shaped thing (a plastic bottle will work)

* little motor and fan

* led lights

* batteries and battery-holder

* switch

You will need these tools too:

* hot glue gun

* soldering iron

* screwdriver

* saw

Step 1: I+D

I searched for "fake fire" on the Internet and only found some small
devices with a noisy fan and a couple of leds. And, worst at all, powered by 220VAC.

I needed something safer and as silent as possible, so I searched on my broken toys box for a liitle DC motor. Then, tested it with many fans (even some 3d printed ones) but results were discouraging.

Days passed and I did not find a good solution. When fortunately, in one of those one dollar store, I saw a little kit of electricity experiment for kids. It included a motor, fan, wires, switch and battery holder. I took it home, tested it, and woah! It worked really well!

I also made some experiments with differents materiales for the flames: silk, paper... and cellofan stripes got the best effect.

Step 2: Inner Mechanism

Cut a 20 cm piece of PVC pipe (a tough plastic bottle will work). Cut out three or four rectangles at the bottom as air inlets.

Prepare the motor, soldering wires to its terminals, and attach the propeller.

Cut a piece of wood as long as the inner diameter of the tube. Carve a semicircular groove to accommodate the motor and hold it with a piece of PVC or a strip of rubber from a tyre. Another option is making a circular hole in the piece of wood, and glue the motor in it.

Use a couple of screws to hold this piece of wood inside the PVC pipe. Fan should not stand out the top of the container.

Grab your christmas lights and glue them evenly around the top of the pipe.

Step 3: Flames

Cut a piece of a plastic grid a little bigger than the mouth of the pipe.

Use a pair of scissors to cut some irregular stripes of cellophane of different sizes. Mix yellow, orange and red if possible.

Lengh of stripes depends on the power of your fan. Start with long stripes, test the motor and chef if the flames flutter properly. If not, chop the top of the flames to make them lighter.

Use normal glue to stick the stripes to the grid. You can use your glue gun but cellophane melts with heat, so poor the glue on the grid and then attach the stripes to it carefully.

Finally, use some more glue to stick the grid to the top of the PVC pipe.

Step 4: Wiring

My Christmas lights have got a plastic case with three AAA batteries. That means 4.5V. But the small motor works with just 3V.

I went the simpler way soldering one wire of the motor (the red one) to the terminal of the intermediate battery.

Lights have got a little switch, but I added another one for the motor. Just cut the red wire, and solder both tips to the rocker switch.

Use some glue to attach the switch to the battery holder and to fix the wires in position.

Step 5: Decoration

Cut a circle of plywood (35cm wide approximately).

Cut five or six thick branches with a litlle angle, so they are leaning but do not touch the inner mechanism.

When you are happy with the angle, screw the sticks to the plywood circle.

Drill a little hole in every branch and pass a piece of wire through the holes. This will be the scafolding for the thinner branches.

Now, grab a bunch of thin branches and use the glue gun to attach them to the base and the wire.

Optionally add some brown paper to fill the gap between the inner mechanism and the branches (y used the stuffing from an Amazon box). Air must flow into the PVC pipe, so do not make this stuffing too dense.

Finally, build a little 'door' with some branches, and tie it to the scaffolding with two piece of wire to access the battery box and its switches.