John R. Bentley 2007.



Naphtha Launch Propeller

Steep pitch and square tips!

This thing is 3 1/4 inches in diameter and has a pitch of about 12 inches




Milling 1/16" slots in the hub for the blades
(I mounted the vise at an angle on the mill table then just cranked the x-axis handle)





Hub screwed on to the shaft





Embryo blades and the threaded hub





A test fit, prior to silver brazing







Still cooling down after being red hot!





Bending the blades in the vise
to reduce the pitch as the diameter increases





Ready to trim the blades and hub in the Craftex lathe



This job could have easily been done in the Taig lathe, but I used the Craftex 7" x 8"



An eagle eye might notice the Taig live center being used here...
- it was held in a 1/2" tailstock drill chuck





A flat needle file ready to go to work on the blade camber





Entry side is done - now to the back side...





Darn near done!





Engine Exterior Construction


Cylinders, Pistons and Rods


Valve Operating Wheel


Vapor Generator


Crankshaft


Auxiliaries


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