Join Date: Sep 2005
Location: New Westminster, BC
Thanked 587 Times in 558 Posts
Rep Power: 17
Re: Guage for aft water tank
You could make your own such gauge pretty easily... Buy a gauge in the appropriate "inches water column" scale, insert your tube from the top to an inch or so within the bottom of the tank, and tee in the gauge and a way to 'pump it up' - a squeeze bulb type thing.
When you force a bubble out of the tube, the pressure it takes to do that is equal to the pressure exerted by the weight of liquid, proportional to the actual height. in the case of a water tank you could read the gauge directly (in inches). In a holding tank you'd need to know the 'density' of the material in the tank so that could be variable.
btw it takes 27.68 vertical inches of water to create 1 psig pressure - gives you an idea of how low a pressure we're talking about.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)