The essential materials for the boat and engine are:
- a brass or copper tube 3mm or 1/8 inch outside diameter, 2mm inside diameter, 50 cm length. For sources see (1) below;
- a narrow aluminium cake baking form (disposable). I prefer to use a size a type about 19 cm long, 6 cm wide and 5 cm high, easily giving the right shape;
- a binder clip with a base of about 2 cm;
- a small aluminium cup, as from a candle light (or you can make something similar from aluminium foil);
- about 1 square cm of double sided adhesive tape (the type without foam, because I am not sure the foam type is heat resistant enough. The foamless kind is, when one side is cooled by the water).
For the bending tool or coiling mandrel you need:
- a sturdy cylinder shape (e.g. piece of wooden dowel), about 2 cm diameter and 3 cm length;
- a piece of scrap wood minimum 4 cm x 15 cm x 1 cm;
- one screw with a length about equal to the thickness of your piece of wood and one screw 2 to 3 cm longer (for each you will need a matching screwdriver, not shown).
- a piece of sturdy tube with a loose fit over the brass or copper tube and minimum about 20 cm long;
For the optional rudder, you need about one third of an extra aluminium form. For this rudder you can print and cut out a helpfull template from the drawing added to step 6.
For the optional decorating you can use permanent markers, common aluminium foil and some more double sided tape.
(1) You can buy the brass tube at modeling shops or at OPITEC
. The article number at OPITEC is 813.716. OPITEC serves Germany, France, United Kingdom, Italy, Switzerland, The Netherlands, Austria, Belgium, Spain and Hungary. You can experiment with shorter lengths (e.g. 12 inch), but lesser coils gives a larger chance the pop-pop cycle stops after a while. To my experience any copper or brass tubing with this diameter is bendable with the mandrel and technique described further. I never found the need to soften the material commonly available.