While the final version of the Mk II will have an electronic push-button trigger for the firing valve, the manual nozzle assembly is used to both pressure-test the frame prior to the final assembly, and as a safety for the electronic valve. It adapts the threaded PVC connection into a standard garden hose thread, allowing use of a variety of nozzles.

Assembly Itself:

The manual nozzle assembly simply consists of an adapter to go from the 3/4” PVC threads to the valve, and then from the valve an adapter to standard hose threads. All parts should be in stock at any Lowe's / plumbing store.

Parts:

2x 3/4” MIP x 1/2” FIP Pipe Hex Bushing (Watts # A-870)

2x 1/2” MIP Pipe Hex Nipple (Watts # A-833)

1/2” Ball Valve

3/4” MH x 3/4” FIP Garden Hose Adapter (Watts # A-669)

Tools & Supplies:

Teflon Tape

8” / 7/16” Adjustable Wrench

13/16” Wrench

Assembling the Parts:

Since the manual nozzle assembly is a straight line of adapter-valve-adapter, there isn't really anything tricky about assembling it. Start from one end, start from the other, even start from the valve in the middle.  Pictures follow of when I assembled it.