GGDT Design Library

Orbit WaterMaster
1" Sprinkler Valve

Perhaps the most popular valve in the pneumatic spud gun world is the Orbit Model 57461 Watermaster. They are cheap, plentiful, and easy to modify to pneumatic operation.

Why do people modify them to pnuematic operation? Because such modifications dramatically improve the valve's performance in this application. Remember, sprinkler valves are not designed to open/close quickly. In fact, for sprinkler systems, opening quickly is bad as it can damage a sprinkler system. So if you want anything that resembles good performance from your sprinkler valve, you will modify it to pneumatic operation

Those who are unfamiliar with how to modify a sprinkler valve from electric operation to pneumatic need only take a quick gander over here. If after reading those instructions you still have questions, then they will no doubt be answered by the goons over at the Spudtech Forums (but unless you like being abused, I suggest you read that first page before you start buggin' the goons).


And now for a very slight change of subject in the name of full disclosure...

Unfortunately, the WaterMaster (and all other mass-produced sprinkler valves to my knowledge) is not a piston valve. It is a chamber sealing diaphragm valve. This will lead to inaccuracies in GGDT's modeling of the valve, but these inaccuracies shouldn't be prohibitive.

With all that said, below is the list of input parameters that I feel best model the performance of the Orbit 1" WaterMaster. Note that other sprinkler valves should have pretty similar performance, but in all honesty I've not done enough homework on that topic.

Valve Type
Chamber Seal
# of Valves
Flow Coef
Seat Diam
1.2 in
Dead Vol
3.1 in^3
Piston Diam
2.0 in
Piston Mass
22 gm
Vent Diam
.15 in (1)
Pilot Vol
1.1 in^3 (2)
(1) Will vary depending upon exact modifications made. This value represents a generic blow gun.
(2) Will vary depending upon exact modifications made. This value represents a vent mounted directly to the valve body with no extra tubing/etc.

Return to Library Menu

Note: If you came here via a direct link from somewhere else, odds are you'll want to click here.