Intro: Spitfire Desk Fan.
This instructable is for how to add an extra dimension to your model aircraft; a working propeller (and lights!) which is surprisingly good as a desk fan. It can be adapted to any aircraft of most scales, although you would struggle to fit it into anything smaller then 1:72 scale. You could also use the same principles to make one of those plane-on-a-string things that fly round in circles, or even make an r/c version! I am assuming you know model-making basics such as glueing, painting and adding transfers (if you want advice on these, there are loads of good websites and other instructables on this).
You will need:
A Model Kit (mine was an Airfix 1:72 scale Spitfire mk1a)
A micro-motor (I got mine from an old r/c boat; also available from the internet, including here: http://www.wheelspinmodels.co.uk/i/93255/)
DPDT Switches x2
Quality cardboard (about 2mm thick)
Craft knife (I used a small pocket knife)
Soldering iron + solder
In all, mine cost me £7 (about $10, I think), £5 for the kit and £2 for the paint. I had all the tools and glues already. If you were buying the motor, this would add another £4 to the cost. It's a cheap and cheerful project, this one!
Step 1: Pre-painting the Kit.
This stage is optional, but saves time later on and also results in a better finish.
Paint all small, non body-coloured parts (such as the prop, wheels and exhausts) while they are still attached to the plastic frame. These parts are glued on later, after the body has been painted and this reduces paint bleed and overlap.
Follow the instructions for the kit until you get to putting the fuselage together. This is when we add the Motor (and lights if you have the space).
Step 2: The Electronics.
This is a simple bit of wiring and took me 5 minutes max. Wire together the motor and a switch, using a reverser if you want. I used one so I could have the Spitfire in fan mode (pushing air away) or in realistic mode (i.e. the prop going the right way). This is made from a DPDT slider switch, as shown in the diagram. The lighting circuit uses LEDs powered by a 9v Cell and the Motor from a 1.5v AA cell, hence the DPDT toggle switch used to turn both circuits on. I eventually left the lights out of my Spitfire, purely due to size issues as I didn't have fine enough wire to fit into the slim wings.
Step 3: Installing the Motor.
First, the prop needs to be drilled to fit onto the motor shaft. Use a drill the size of the motor shaft in a pin vice (this makes the hole more precise). Then glue the motor on using the bodger's solve-all, aka cyanoacrylate glue, aka SuperGlue. Then glue the motor into the front of the fuselage. You may need to remove some material from the sides of the fuselage (I did) to make the fuselage fit together properly. Trail the wires out of the wing-mounting position, through the wings and out of the bottom of the aircraft. To fit lights, if you are doing this, you will need to drill mounting holes in the wings for the landing lights and run the wires out the same way as the motor ones. Then glue the pilot and other fittings in place before assembling the fuselage and wings (see pictures).
Step 4: Painting.
I won't tell you how to paint, but it is useful to have the correct colours for your plane. I had the wrong shade of brown, but it seems to have come out ok. Also, wait until the main body is dry and finished before adding the pre-painted parts for a better finish.
Step 5: Making the Base.
Mine is made from good-quality card; if you are a woodworker, you could make something much better-looking. Basically it is a box made up of a 150x150mm top piece, and 4 25x150mm sides. Mine also has a shelf for the electronics to rest on. First, cut the top piece to size (this will vary according to what size your model is), then cut the sides. Cut the shelf the same length as the sides, less 2 times the thickness of your card. The width is up to you. Run the wires from your model through a hole in the top piece and position the main switch, then cover it in something; you could have it look like grass or (as I did) paint it to look like tarmac. Then glue the plane in place (with the old cyanoacrylate). Next, assemble the sides to form a square, and add the shelf in the bottom. Let the glue dry, then attach one side of the top piece. When this has dried, you can then glue the rest of the base on square to it.
The final step is to add the transfers to your model (I didn't do this earlier as I didn't want to damage them by handling them too much).
Thanks for reading this and enjoy your version!