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Back into the Dark - Parts List for 16x20 Tank

US Plastics Parts List for 16x20 quick dumping archival print washing tank:

(1)    24x12x18 Polyethylene Tank, (Part 6309), $70.70.  Optional lid (Part 6358), $24.

Installed Tank Fittings

(2)    1" PVC fitting, (Part 16453), $18.62.  This is the bottom corner outlet. This can be larger but then the valve and hose is difficult to manage.  A 1" fitting will drain 25 gallons in 1.5 minutes.

(3)    1/2" PVC fitting, (Part 16451),  $15.51.  This is the top cornet inlet.  This can be smaller then 1/2 inch but then fill-up time is increased quite a bit.  Mine is stopped down to 1/4 inch and it is slow.

(4)    1 1/2 " white threaded MIP ball valve, (Part 22011) $10.13.  This is the outlet valve for the 1" PVC fitting.  The outer threads on the fitting are 1 1/2" while the inner threads are 1".  A 1 inch ball valve can be used here with a one inch PVC nipple.  This will decrease the out flow rate for total dumping but it is easier to get hose in the smaller size.

(5)    1/2 to 1/2 hose fitting, (Part 62172), $1.05.  This connects the upper fitting to a hose.

(6)    1 1/2 to 1 1/2 hose fitting, (Part 61160), $0.94. This connects the outlet ball valve inner threads to a 1 1/2 inch (inner dimension)  hose.  Note:  1 1/2 hose is difficult to find so 1 1/4 outlet may be preferable.  It increases the dump time, but not by much.

(7)    24 x 48, 1/16 thick low density polyethylene sheets (5), (Part 42569), $39.20 total.  These are the separator sheets.  With 5 sheets you can cut 15 separators to 16 x 22, or to other dimensions.  Remember that the low density poly will float in the tank so weighting will be necessary.  Note:  1/8th inch sheet adds rigidity  and is preferable

(8)    5/16" OD by 3/16" ID (Part 44018)  acrylic hollow rod.  This is cut for the spacers.  A better dimension is 3/8 OD by 3/16 ID. 3 feet at $.13/ foot.  $0.40.

(9)   1/8 inch or so threaded metal rod about 11 inches long with two nuts and washers each, two.  From local hardware store.

(10)    Clear suction Delivery Hose (1 1/2 inner diameter), (Part 54253), $3.36 for 3 feet.  Note:  This hose is really thick and difficult to handle but the only 1 1/2 inch hose available.  A clear vinyl hose is preferable

(11)    Clear vinyl Hose (1/2 inch inner diameter with 1/16" wall), (Part 59017 ), $1.26 for 6 feet.

(12)    Hose clamps from local hardware store.

Total Price  including $9.00 delivery is $170.00

The tank is delivered with the fittings installed.  The construction consists of cutting the separators and the spacers, and drilling two holes in the separators for the threaded rod and spacers.  A wood saw and a drill with a 1/8th bit is all that is necessary.  As an additional measure I'm considering adding an overflow hose, but really this is not necessary if your soaking the prints without any flow in the tank.

Notes on Construction:

1.  1/16 inch separators may be too flimsy for a large tank.  Solution (a) is to add a row of spacers through the bottom center of the separators and a row each on the top corners leaving enough space to slide paper in.  Solution (b) is to use 1/8th inch separators.

2. 1 1/2 inch hose is difficult to find.  The 1 1/2 inch delivery hose is too difficult to work with so isn't recommended.  If an outlet hose IS needed the best solution is to go with a 1 1/2 to 1 1/4 inch hose fitting and a vinyl 1 1/4 inch outlet hose. 

Notes after one year of use:

1.  Filling the tank is the most difficult aspect due to the time and attention needed.  I found I used a small flow in the tank prior to archival washing so an overflow regulator was definitely helpful.   The volume of water needed for a soaking wash is far more then is required.  Another method which is far more efficient would be to stack prints in a tray with a hydrophilic membrane between each sheet.  An example of such a membrane is a diaper lining, it allows the water to freely flow through without uptake.