I have 2 Gravity Works print washers, a 16x20 and 11x14. The water enters at the bottom at one end, but into a vertical chamber an inch in width, with holes which direct it into the "slots" with the prints. There is a "false bottom" below the prints, perforated with holes which allow the water to drain down. The water exists from an area at the end of the washer from the area under the false bottom (opposite end of the tank from the supply). The exit hose has a nice stepped clamp, which controls the exit rate, the key to the timing of water changes.
You adjust the inflow (after filling the washer) so that it stays level at the top, to balance the exit rate. I think mine is about a quart every minute, or a bit less. I also have a temperature controlled valve with which I can tweak the inflow rate.
There is also an exit tube with hose at the top, as an overflow protection. (opposite end of the tank from the supply) I set the exit clamp to position 3 (based on testing), adjust the inflow so that the water just begins to exit the overflow pipe at the top (just a dribble, to insure the tank doesn't drop in level.
I read something years ago which stated that washing fixer and chemistry out of fiber paper takes time (where the "diffusion" thing comes in) and that 2-3 hours of just moving water is more effective than the same number of exchanges over a shorter period of time. I don't know where the sweet spot is, this is my ditty.
You adjust the inflow (after filling the washer) so that it stays level at the top, to balance the exit rate. I think mine is about a quart every minute, or a bit less. I also have a temperature controlled valve with which I can tweak the inflow rate.
There is also an exit tube with hose at the top, as an overflow protection. (opposite end of the tank from the supply) I set the exit clamp to position 3 (based on testing), adjust the inflow so that the water just begins to exit the overflow pipe at the top (just a dribble, to insure the tank doesn't drop in level.
I read something years ago which stated that washing fixer and chemistry out of fiber paper takes time (where the "diffusion" thing comes in) and that 2-3 hours of just moving water is more effective than the same number of exchanges over a shorter period of time. I don't know where the sweet spot is, this is my ditty.
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