Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

As requested, a bit of photography to show the innards. I needed to build the outlet side valve anyway, and remembered to do the pic before assembly.

The photo shows, from the top, a block of wood that may serve as integral cylinder and valve head.



Second row down we have the outer valve body barrel. 1/4 OD brass.

Third row down is the middle layer, a cage made by slotting the tube in four places around the middle, leaving intact rings at the ends. The purpose of this bit is to support and position the inside bits, control the ball motion so it stays in its straight line, and allow much more water to psss than would be possible using a straight tube. The slots greatly increase water flow area.

Forth row shows the inlet bit of the innermost layer, with a tapered seat cut for the ball. The BB itself, and the outlet nipple, with the notched skeletonized end facing the ball.  The idea is to maximize available water flow around the ball when it is not seated, yet retain control of the ball travel to insure it will seat, even when used upside dow or sideways. .  The notches in the outlet side allow water to pass the ball, which otherwise would be seated against it, since the design uses no spring.
This end gets a nipple to connect an output hose.

Bottom row is the assembled inlet side version of the valve. The only difference is the inlet side has a hose barb and the outlet side has the barb cut away to allow the body of the valve to be glued into a port drilled in the valve block/cylinder head.

The overall idea is minimum back pressure, maximum flow. That will allow the piston pump to gr tun faster without overloading the system.