Archival Soak

I am interested in your feedback on the following workflow and thought process in an effort to achieve an archival wash while conserving water.

The Workflow
-1st fix bath 30 seconds (Ilford Rapid Fix 1:4)
-2nd fix bath 30 seconds (Ilford Rapid Fix 1:4)
-30 second running water rinse on each side of the print to remove the surface fix (on a sluice board)
-5 minute wash in a tray with a Kodak tray siphon (about 3 changes in the 5 minutes)
-10 minute Perma Wash – Wash Aid
-30 minute soak in Vertical Print Washer (with 2 pumps circulating water)
-30 second running water rinse on each side of the print (on a sluice board)
-squeegee and dry

My Thought Process
-Homemade 11x14 Vertical Print Washer holds 16 8x10 prints and 30L of water
-Washer is outfitted with two aquarium pumps that circulate at 4L per minute
-8x10 Ilford MGIV Fibre weighs about 15 grams dry, and 20 grams wet
-assume wet weight is totally due to embedded fixer
-assume 1 gram of fixer has a volume of 1 mL (just like water)
-16 prints x 20 mL of fix per print = 320 mL total
-320 mL of embedded fix being diffused into 30L of water
-Ratio of water to fix ~94:1

-30L of water is constantly being circulated to bring less concentrated water / fix solution to the paper-water interface
-30m soak with constant circulation
-no changes of water
-should allow enough fix to be diffused out of the print to be considered archival when followed by another 30 second running water rinse on each side of the print.

I have read most if not all of the various threads and have decided to start with a 30 minute soak but I am also planning a test using the HT2 solution (thanks for the help with the HT2 Mike!).

Again I am interested in your comments.

Todd

Looks good to me. I assume you use fiber based paper. Seems like 5 minutes in PermaWash would be sufficient.

I rinse the print briefly between PermaWash and the washer.

I would not go to all of that work and then use a squeegee. I have not had any problems drip drying the paper from a clip. Aslo, using a squeegee implies that you put the washed print on a surface (I assume the same sluice board you used in an earlier step) that might not be clean.

[QUOTES=Todd Barlow;374480]
"...two aquarium pumps that circulate at 4L per minute"

No fresh water flow?


"...15 grams dry, and 20 grams wet ... due to embedded fixer
-16 prints x 20 mL of fix per print = 320 mL total
-320 mL of embedded fixer"

I only count 80 ml, 5ml x 16. Dan

No fresh water

No fresh water intake into the vertical washer. The fresh water comes from the initial rinse after fix 2, 5m wash, 10m wash aid and a 30s rinse after the soak.

You are right about the calculation, should be 5g / mL X 16 = 80.

Ratio of Water to Fix is 375:1. (Diffusion stops when the embedded fix is of the same concentration as the water at the paper / water interface and decreases as the concentration increases, however the soak follows a 30s rinse, 5m wash, 10m wash aid, 30s rinse, by the time the prints are put in the vertical washer the ration of water to fix could be even higher 375:1)

Would fresh running water in the washer make a huge difference? I will test but am intertested in your comments about the approach.

Thanks

Todd

[QUOTES=Todd Barlow;375001]
"... by the time the prints are put in the vertical washer the
ration of water to fix could be even higher 375:1"

I'd think by a factor of 100 or more. A factor or 1000
would not surprise me.

"Would fresh running water in the washer make a huge
difference? I will test but am interested in your comments
about the approach."

I see .02 gram/square meter of paper mentioned as
an upper limit. Divide by 20 for an 8x10. At equilibrium
that amount wash water which is retained in the paper
should be no more than that. Your final rinse allows for
a little margin. I sponge dry. Sponge or squeegee
some fluid is removed. Must consider everything.

Your pre-washing I think likely has brought thiosulfate
levels low enough for the soak to achieve an archival
finish. As sure as you can be is to accept only a NO
stain what so ever when using the HT-2 test.

BTW, how do you process; one print at a time, when
do you hold? Dan