There are pipe fitters and there are pipe fitters.

My dad has a pond with a small earthen dam on his property. He needed to lower the level to repair a rusted galvanized overfill-drain pipe. How does one do that cheaply? Make a siphon, right?

Well, making a siphon is actually pretty complex when you're moving a bunch of water. Sizing it can be tricky - you don't want turbulent flow (bubbles will break the vacuum) and you don't want it to be too small (takes too long) or too large (expensive, hard to start for small drops). https://www.youtube.com/watch?v=8rgpRJ1xCeM and https://www.youtube.com/watch?v=QLyknJHxGz0 are a couple of decent videos (check the descriptions).

There's lots of interesting physics and math behind figuring out how to move fluids. Reynolds number and so forth.

Copper's too expensive to use in most new houses these days, so plumbers need to understand new types of fittings, how various adhesives work together, what's a safe solder and why, etc. Sure, trade schools can teach that, but knowing the "science" behind the stuff is valuable too, especially with the pace of technological change these days.

Cheers,
Scott.

Post #410,482 by Another Scott 5/27/16 2:08:41 PM 5/27/16 2:08:41 PM Reply	There are pipe fitters and there are pipe fitters. My dad has a pond with a small earthen dam on his property. He needed to lower the level to repair a rusted galvanized overfill-drain pipe. How does one do that cheaply? Make a siphon, right? Well, making a siphon is actually pretty complex when you're moving a bunch of water. Sizing it can be tricky - you don't want turbulent flow (bubbles will break the vacuum) and you don't want it to be too small (takes too long) or too large (expensive, hard to start for small drops). https://www.youtube.com/watch?v=8rgpRJ1xCeM and https://www.youtube.com/watch?v=QLyknJHxGz0 are a couple of decent videos (check the descriptions). There's lots of interesting physics and math behind figuring out how to move fluids. Reynolds number and so forth. Copper's too expensive to use in most new houses these days, so plumbers need to understand new types of fittings, how various adhesives work together, what's a safe solder and why, etc. Sure, trade schools can teach that, but knowing the "science" behind the stuff is valuable too, especially with the pace of technological change these days. Cheers, Scott.
Post #410,484 by boxley 5/27/16 2:23:54 PM 5/27/16 2:23:54 PM Reply	huh? drill thru the base of the dam, throw in a pvc pipe $400, plug when water is low enough always look out for number one and don't step in number two
Post #410,487 by Another Scott 5/27/16 2:37:29 PM 5/27/16 2:37:29 PM Reply	Is that how the British Navy does it? ;-p https://www.youtube.com/watch?v=H9XEMUfbzN0 You don't go messing around with dams, and you don't do anything to weaken them. (Yes, I know you were just yanking my chain. ;-) Cheers, Scott.
Post #410,490 by boxley 5/27/16 2:51:41 PM 5/27/16 2:51:41 PM Reply	that is how it should have been built to begin with, a safety valve :-) always look out for number one and don't step in number two

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