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adamc
13-Apr-2011, 10:29
I acquired a stack of used plastic trays yesterday. None of them are labeled specifically as Dev, Stop, Fix, etc. and they are crusty. The guy I got them from mentioned that he hasn't done darkroom work in about 5 years, so I'm assuming that crust has been sitting on them for quite a long time. I'm a bit concerned about contamination, is there a good way clean the trays so I don't need to worry about contaminating my working chemicals? Would distilled water draw chemicals out of the plastic? I have some darkroom soap, it's kind of gritty, but beyond that I'm not really sure it does anything different than regular soap.

Is this something to be concerned about, or should I just scrub the hell out of them and not worry about it?


Thanks,
Adam

Mark Woods
13-Apr-2011, 11:22
If the tray is whitish, it's probably hypo. Smell them, and if one's acidic, that's the stop. And the last is developer. I've used my dad's trays that have to be 60 years old and work great. I did have to put resin on one that cracked.

Bob McCarthy
13-Apr-2011, 11:23
Clean developer trays with an acid, clean fix trays with an alkaline is what I would do.

Nothing is going to soak into a plastic tray.

bob

joselsgil
13-Apr-2011, 11:27
Water, soap and air dry. Test them, with a test strip of paper, if you doubt that they are clean. Be sure to mark them; Dev, Stop, Fixer, Wash, for future reference.

adamc
13-Apr-2011, 11:38
Cool. Thanks guys!

jp
13-Apr-2011, 11:54
The darkest one is probably developer.

I'd suggest soap and wanter. A little oxyclean or simple green is good too, but be sure to rinse it off well as you would with soap. Some cosmetic staining of the trays is normal. Don't go too crazy buying cleaning chemicals as new trays aren't that expensive either.

tgtaylor
13-Apr-2011, 12:07
Formula for Kodak TC-1 Tray Cleaner:

Water: 1.0 liter
Potassium Bichromate, anhydrous: 90.0 grams
Sulfuric Acid, concentrated: 96mL

Pour small volume of TC-1 into the tray and slosh it around. Then pour out and wash the tray with water until all traces of the cleaner disappears.

Note: Add acid slowly while constantly stirring the cold solution of the bichromate.

Thomas

Louie Powell
13-Apr-2011, 15:46
The tray with the black stains is the developer tray. Hypochlorite bleach (Chlorox) will bleach it down to something approximating white, but there will still be a layer of silver that will gradually darken over time as you use it. Not a problem - just note which one it is, and reserve it for use with your developer.

Neither stop nor fixer leave truly permanent contamination, but that is not to say that they won't have a layer of dried whatever. Stop bath will simply rinse off; fixer is a bit harder to remove, but once again, the secret is hypochlorite bleach. A very brief rinse in hypochlorite bleach will neutralize any residual fixer.

Just make sure to rinse the trays in plenty of fresh water after bleaching them.

adamc
13-Apr-2011, 16:54
Great information, I'll get these neglected trays back in proper working condition in no-time. Thanks to everyone for sharing the knowledge.

Howard Tanger
13-Apr-2011, 17:11
I acquired a stack of used plastic trays yesterday. None of them are labeled specifically as Dev, Stop, Fix, etc. and they are crusty. The guy I got them from mentioned that he hasn't done darkroom work in about 5 years, so I'm assuming that crust has been sitting on them for quite a long time. I'm a bit concerned about contamination, is there a good way clean the trays so I don't need to worry about contaminating my working chemicals? Would distilled water draw chemicals out of the plastic? I have some darkroom soap, it's kind of gritty, but beyond that I'm not really sure it does anything different than regular soap.

Is this something to be concerned about, or should I just scrub the hell out of them and not worry about it?
Thanks,
Adam

A couple of tablespoons of sodium carbonate (aka soda ash or washing soda)in a gallon of very hot water; pour this solution into the trays and let them stand overnight. The next day rinse them well in warm water and they should be nice and clean. Howard Tanger