The 'Hot Box' Cabin Heater
Hot Box dimensions
This box is 9" square by 18"high. The sides are formed from stainless sheet, the edges bent in to allow the rivetting of similar sheet, folded to form the front, back, top and bottom.
An extension of the bottom at the front is bent vertically downwards to allow fixing to the locker front. The back extends upwards 3½" from the bottom. Then there is a 3½” gap.
After that a single sheet extends
11" to the top, and extends 3½” down the front.
Followed by a 2" wide bar which extends 2" each side
of the box, for fixing to the locker front. The door is 31/2" high
with stainless steel hinges rivetted to the bottom, having a 9" high
gap at the front for heat and light to come through.
Exhaust gas ventilation
A right angled cast iron galvanised water pipe in the middle of the top left hand side takes much of the exhaust gasses and water vapour up a flexible water pipe to a deck fitting made from copper pipe and brass plate. This goes through the forward part of the Dorade Ventilator box.
Inner workings
Inside, the base of the Tilley lamp is held tightly by the sides of a folded aluminium tray rivetted to the bottom, and a folded aluminium wedge rivetted to back of the door. The Tilley lamp gives out about 1 kilowatt and can withstand down draughts. A wick-burner gave an unreliable flame and at around 2 kilowatts, a primus stove proved to be dangerously hot.
The Tilley lamp will last all night on one filling, though may need an intermediate pump-up. It maintains a very pleasant atmosphere in the cabins and an even more cosy atmosphere in the heads compartment when the saloon door is shut.
The box gets hot, but does not scorch the paint and the upper fixing lugs are never too hot to press a finger against. If making another I would make it approximately ½” narrower, to fit the original locker width. Tilley lamps are no longer commonly available, but can be obtained from Webbs, Ironmongers, Tenterden, Kent and from Rutherfords of Earlston, in the Scottish Borders, who also carry spares.
John Curtis, Draig-y-Moor