Heat water in an old frying pan on an electric hotplate, or use an electric frypan.
Place a smaller old saucepan in the water so the 2 pans act as a double saucepan. For safety's sake don't do this on a gas burner; both the linseed oil and the gum turpentine are flammable and the mixture will catch alight if splashed onto the gas flame.
In the saucepan, place 250g of beeswax, 250ml of gum turpentine (not mineral turpentine) and a splash of boiled linseed oil. Stir the mixture with a clean wooden stick until the ingredients are combined and form a clear liquid.
Pour the liquid into steel containers with lids, such as old tobacco tins or similar. Let the mixture cool completely and set to a milky, waxy paste.
Set the paste aside for use later on - don't worry, it will keep for years.
[Creative Common Photo: Marshall Astor - Food Pornographer]