April 9, 2009

Progress on machining cylinders

Work is nearing completion on the back side of the cylinder castings.  The casting are finished to length on the rear.  This series of photos shows center drilling & hole drilling for the stud holes.  24 studs for each cylinder and 12 studs for each valve. Threading is the next step.

Measurement and design work has begun on all the rods.

center drilling stud pattern on right rear valve and cylinder casting face.
Photo: Steam Operations Corporation
center drilling stud hole pattern on right rear cylinder casting.
Photo: Steam Operations Corporation
drilling stud holes on right rear casting. These holes will be threaded for applying studs to secure the cylinder and valve heads.
Photo: Steam Operations Corporation
completed holes on right rear valve and drilling holes on right rear cylinder.
Photo: Steam Operations Corporation
This is a CAD drawing of the locomotive rods with current size of rod brass bores and crank pin diameters with a comparison to the new, as built dimensions. This is the first step in engineering future serviceability using standard practice.

 

 As additional information the 786 uses a floating brass arrangement on all side rods as an improved design over a more common practice of brasses that were pressed into the rods preventing them from rotating.

 


Photo: Steam Operations Corporation