Foaming RA4 Developer

[L Gebhardt]

I'm using Kodak RA4 in an Ilford ICP42. Image wise I am not having any trouble, but I am having an issue with foaming in the developer. This is Kodak RA Developer Replenisher RT mixed per Kodak's recommendations with starter. I also replenish it.

The foaming is causing me to stop and clean developer out of the input roller area, which is supposed to stay dry. If I lift the top plate in the tank it's very foamy.

I only run RA4 through this, and it has had many washings and chemical changes since it was setup for Ilfochrome.

Also, I run a mix of Kodak Endura and Fuji Crystal Archive papers.

Any ideas on fixing this?

 

[Mike Wilde]

Is this machine new to you?

I suspect that there may be residue of a foaming agent either in the machine or on the rollers, or with the mixing vessels or tubing or any filter in the plumbing circuit you are working with.

The other chance is that a spray arm (if this machine uses one) is missing (so the developer comes from the pump at full volume) or the spray arm is mis -aimed.

How about a run with just water? Any foaming then?

My Fujimoto CP-31 on RA-RT has the spray aerial for about 1/2" before it hits the surface without the rollers in the tank. The addition of the rollers probably keeps the spary arm's output under the surface.

I have noticed a few bubbles when draining the machine into a jug at the end of a run, but nothing as severe as you are seeing.

 

[L Gebhardt]

Thanks Mike. The machine is used, and I don't know the history. I think it was used for Ilfrochome, based on the way it was sold as an Cibachrome processor. I cleaned the tanks out with many changes of water.

There is no spray arm that I can see. The solutions are pushed up through a slot and flow over a stepped plate and then flow down the other side.

Contamination is my first thought, but the funny thing is it will not foam at first. And sometimes I get many days out of the developer before it starts. The developer mixing tools are only used for color developer, but I do mix C41 and RA4 in the same beaker. but it's always washed out well.

The foam looks like whipped egg whites, but slightly yellow color. After three changes of water there is no foaming when running with just water.

I guess it may be time for a more thorough cleaning. Hopefully I can find the manual.

 

[Mike Wilde]

It might be just be that oxidized developer will foam?.

I never leave the developer in the machine for more than a day, or perhaps overnight once or twice a year. I just don't get the chance to print colour that often.

The other nice thing is that my machine works on 1.9l of chems to fill the tanks. My low volume resulted in me thinking twice after cleaning and restoring a 21" kreonite roller processor I was gifted. I ended up tossing it in the dump after salvaging the replenisher pumps, which I plan to graft onto my little cp-31 someday.

Storing used but replenished RA-RT in an almost full 2l glass jug in a cold dark place means I can usually wring 4 months out of a tank worth of developer before the blacks start to look crappy, and the lot is tossed and mixed from fresh again.

 

[Mike Wilde]

Oh - mine came filthy- like drain and never rinse afterword -

I wash mine (all hard rubber rollers - no soft rubber or foam in this unit) running it on dilute toilet bowl cleaner. I place the crossover racks (which never actually see the tank washing solution ) in a tray to bathe in the same solution, and then brush them with an old toothbrush if I think they need some mechanical help to get the cleaning started.

I will leave it running for 24hrs this way to let the cruddies slowly get cleaned out.

Replenisher lines are usually the worst, and get cleaned after being taken apart and then having a wire threaded though. A pipe cleaner or bit of nylon scouring pad will then get pulled though by the wire. The lines in mine were absolutly full of black crud.

Then it is water twice to rinse.

 

[L Gebhardt]

I usually drain the developer in order to replenish it (no replenishment pumps on this unit), since I never quite know how much is left in the tank after carryover. If I'm done for the day I fill the tank with water and drain it the next day. If I won't be printing for a few days I drain all the tanks and rinse them a few times before the final drain. I've never taken the unit appart, so I'm scared to see how much crud is in the lower part.

Oxidized developer is an interesting thought. Maybe I'm not replenishing enough, though the colors look good. Also, test strips still read the same even when the foaming has started.

 

[Mike Wilde]

I just feed it 20ml of RA-RT replenisher strength dev and b/f per 8x10 size of print and it kind of acts like the energizer bunny...

I pull the cover and pour mine in after about 6-8 prints have gone though. My unit has individual tank overflows, and the proper tank level puts the fliud to just about out the overflow when the roller racks are lowered into place. I pour at the no overflow end, and figure the tank pump has it mixed well enough that not much vorgin makes it out the overflow at the time I am pouring it.