John R. Bentley 2008.



Stack and Smokebox

From the Naphtha Engine's Flash Boiler - constructed from the 1887 patent drawings of Frank W. Ofeldt

The top was turned from a very large brass nut
The brass pipe is in correct scale with the prototype - it was made from a standard 1.5" kitchen sink drain



CONSTRUCTING THE SMOKEBOX:


Note in this picture that the stack band is loose as it not yet attached







A piece of Flowering Crab for the smokebox form







Applewood is close-grained and quite hard







Smokebox dimension marked out in pencil



(I rubbed beeswax into it while it was spinning)



Two-inch brass tubing scavenged from our old bathtub drain/stopper/shower







Cutting a suitable length in the horizontal bandsaw







Ready to start!







Annealing the pipe - for the first of a dozen times







Squishing the pipe in the bench vise to the maximum required diameter







Pounding it over the form







Looks like a piece of Babylonian pottery!







Screwed on to the form - and put back in the lathe for finishing







Polished up a bit, awaiting trimming to proper length







The underside



There will actually be an inner liner of stainless steel at the base of the stack
( and an insulating lining inside the smokebox to reduce heat discoloration )



Mocked up in position over the vaporizer assembly







Finished Stack and smokebox





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