Male Halkey Roberts Valve Connector to 1/4" NPT Female Adapter

This is an adapter for connecting a pump with a male Halkey Roberts connector to a 1/4" NPT fitting. The adapter is intentionally slightly longer than it needs to be, which WILL NOT lock into place on the Halkey Roberts connector by default. I sanded the end of the adapter by placing a piece of sandpaper on a flat surface and rubbed the adapter on top of it to sand it down. I periodically test fitted the adapter until it was able to lock into place with good tension. Alternatively you can alter the 3D model to accomplish the same thing, but I found it easier to print once and sand for a perfect fit. The sanding method should only be used with models printed with 100% infill.

This adapter makes a seal by pressing flatly against the gasket on the male Halkey Roberts connector, which is slightly different than how this connector would make contact with a proper Halkey Roberts valve. For my use case this has been fine, but just be aware of this difference in case it impacts you.