The invention provides an apparatus for generating heat and transferring the heat to a heater head of an external combustion engine, preferably, a Stirling engine. In an embodiment, the system comprises a gas compressor including a gas inlet in fluid communication with an associated gas source and a gas outlet. The housing includes ventilation holes to allow air to circulate through the controller and between the housing and the user’s hands. In one embodiment, the spinner includes a motor and one or more rotational members for engaging the first tubular. The metal plated lands are polygon in which the number of sides is an even number and each pair of facing sides are parallel, and the lands have circular concaves at all the corners and the sides of polygon are arranged to be parallel to the sides of the neighboring metal plated lands.