Machining the valve bodies and lower guide blocks and the valves.
These parts did not scale up double size as to look proper so I went off in another direction.
After squaring up the aluminum stock for both haves I rough drilled thru and did a short location bore on position in each block.
The final bore will be for a .750" x 3" long 660 bronze bushing that will be Loctited in place. This will be the liner for the valve rods. The valve rod will be .500" 303 ground stainless steel bar stock.
The locating bore is used at the lathe to accurately locate the part in the four jaw chuck. The finish bore will be completed here. Only varied less than .002" off center at the opposite end.
Pictured with the bushings installed.
At the mill the mounting holes were drilled 17/64". The air passages were drill 3/16" and a spot face for a o-ring was done. This will be where the valve body mounts to the head. The layout lines visible show where the intake and exhaust ports are drill on the sides.
There are two bushed lower valve guides the will also serve as a location for a made dog point screw to to prevent the valve rod from turning.
Machining the blocks and turning bushings at the lathe.
The guides prior to tapping a 10-32 thread in the sides for the dog point screw.
A quick over view of the valve rod. Cutting a slot in the end for a 1/2" diameter ball bearing.
A view of the valve rod with the key way milled, bearing installed and turned air passages. I will be adding the valve springs in the end of the valve block with a cap on the end. A short counter bore in the end of the rod for the spring.
The springs will not be visible when assembled.