"Ball valve" for PVC drain pipe

[PhoneGuy]

I put together a cabinet using "Ken's Pachinko Cabinet" plans. I was not sure his slide gate would work out for me. I came up with a fairly simple alternative that may be useful for others here. It should be easy to retrofit in an existing cabinet that uses a PVC pipe to feed the balls into the inner hopper. I'm sure this can be refined but it seems to work well for me.

I have a shaft coming out of the PVC drain hole that extends several inches above bottom of the cabinet hopper. A half turn clockwise closes the drain. A half turn back opens the drain.

Use a spindle that blank CDs come on and a paint can cap that fits the over the PVC pipe snugly. Trim the base of the spindle so that the circular base is the same diameter as the outside of the PVC pipe. Trim off half the of this circular base leaving the spindle shaft with a half circle base. Trim the top of the paint can lid leaving a lip that just covers the PVC pipe end. Either trim the paint cap so the only a half circle is removed or trim it all out and glue another half circular piece of plastic to it. Glue a small tab to the bottom of the spindle base. Cut a notch in the half circular part of the paint cap that lines up with the spindle tab.

I then used some scrap pieces of plastic and hot glue to make a scoop on the spindle base so the balls would not have a flat surface to collect on. The spindle base fits into the cap. The cap slides over the PVC pipe. The spindle base is sandwiched between the lip on the paint cap and the bottom of the PVC pipe.

I'm not sure the scoop is actually needed but I put one on my prototype when I was trying to figure out why the balls were jamming up. I think the key is to have no lip at the bottom edge of the PVC pipe when the valve is open.

[PhoneGuy]

A few more pictures.