Apr. 7, 2008.
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
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
VAPOR GENERATOR (naphtha boiler) main page
NAPHTHA LAUNCH ENGINE PLANT main page
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