Replenished D76 foaming excessively

[mshchem]

 

[mshchem]

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[MattKing]

Are you suggesting a switch from distilled to filtered water?

Perhaps. Or two pre-rinses.
The surfactant is probably incorporated, along with other components, in order to permit use with most tap water.
And of course any problems that might arise from a tendency to foam may be related to your particular choice of reels, tanks and solution volumes, and not be of concern with respect to different reels, tanks and solution volumes or commercial roller transport, dip and dunk or deep tank lines.

 

[pbromaghin]

Perhaps. Or two pre-rinses.
The surfactant is probably incorporated, along with other components, in order to permit use with most tap water.
And of course any problems that might arise from a tendency to foam may be related to your particular choice of reels, tanks and solution volumes, and not be of concern with respect to different reels, tanks and solution volumes or commercial roller transport, dip and dunk or deep tank lines.

Two pre-rinses? Do you recommend any minimum time for each?

The equipment in question are Kinderman reels and tanks, but for the last 5 HP5+ rolls I used an old Jobo 2336 tank that strongly resembles a Patterson system. I have been using all of these for 10-15 years with no problem

 

[pbromaghin]

Why wouldn't all film and paper manufacturers require these agents? I'm not buying the Ilford films froth. They don't (or Kodak, Foma, Fuji) in my processing.

It's the water, or contaminated chemicals, or reused containers....the list goes on and on before I would suspect it's Ilford film.

I used distilled water for developer, stop, fix, and HCA. Tap water rinse was the Ilford Method on steroids - a fill and 20 inversions, followed by HCA for 7 minutes and 5 refills with up to 40 inversions, and Photoflo AFTER removing the film from the reels. None of the equipment has been touched by Photoflo for at least 4 years. Prior to this, the quart-sized coffee creamer bottles ("Half and Half" in the US) used for the D-76R have been used only for splitting D-76 gallons into 4 quarts for 2 home-brew batches and 1 D-23 batch. The 2-liter bottle of working solution contained cheap soda-pop before this and was thoroughly washed and rinsed. Any contamination the equopment might have introduced was there at the beginning, but the foaming was only noticeable after about 20 rolls and damaged the top reel of 24-25.

The only element, not present at the beginning, that may have contained a surfactant, is the film. See post #9.

 

[MattKing]

Two pre-rinses? Do you recommend any minimum time for each?

The equipment in question are Kinderman reels and tanks, but for the last 5 HP5+ rolls I used an old Jobo 2336 tank that strongly resembles a Patterson system. I have been using all of these for 10-15 years with no problem

Understood.
I'm not saying that anything is necessary faulty, or wrong.
In most cases, foam doesn't really matter anyways. It is only an issue if the result of the foaming is that parts of the film spend too much time in foam, and not enough time immersed in liquid. That relates not so much to the developer as it does to the geometry of the tank and reel combination and the volumes used.
The two rinses would just be more likely to remove any excess surfactant - excess to what is suitable, given the particular nature of the water used to make up the developer plus the constituent other chemicals in the developer. As for the time, I can't really suggest anything particular. FWIW, I always use a single 3 minute pre-rinse, but there is no science behind that other than dependable results, and all the rest of my variables differ from yours.
Commercially prepared developers often have extra components included that deal with water variations, and differences between films. If you are mixing up your own, those components won't be present.
It may just be that through coincidence you have hit on a combination that is both particular to your usage and problematic. So if you change any of the variables - water used, volume used, number and duration of pre-rinses, perhaps even agitation, the change may disrupt everything sufficiently.

 

[koraks]

Why wouldn't all film and paper manufacturers require these agents?

They likely do, but the choice of agents, any mitigating factors and their concentration may differ from one manufacturer to another.
I've never found the foaming to be a problem, but it does occur from time to time.

Btw, RA4 developer foams like crazy - which is also due to the surfactants added to it to promote even wetting. What gives; just spritz it with some ethanol if it's a problem, e.g. when pouring it back into the bottle.

I'd just ignore it frankly; the foam isn't really a problem. It'll die down between sessions and as long as the fill volume of the tank is sufficient, it won't affect development.

Commercially prepared developers often have extra components included that deal with water variations, and differences between films. If you are mixing up your own, those components won't be present.

These are generally sequestering agents. Interestingly, in terms of foaming, they would make your developer foam up more instead of less, since the calcium carbonate 'hardness' in the water tends to suppress foaming. Btw, it's not the water.

 

[Don_ih]

maybe I should just start with a new working solution now

I make only 1/2 a litre of replenisher for a litre of stock. Last time that came to an end, I poured off 1/2 the stock and replaced it with freshly made D76 and also made another 1/2 litre of replenisher. Seems like a good way to go.

Deal with the frothiness by making sure you have enough developer in your tank to completely cover the reel plus a bit more - and rap the tank down on the counter after each agitation.

Also, I use tap water and don't get foam. Maybe the foam is held back by the hardness of my water.