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  1. #1
    Mike Wilde's Avatar
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    An old Roller Transport is now ticking again

    I have processed color prints in tubes for many years. Back to EP2, as it turned out, as I was cleaning off 26 year old chemical storage bottle labels this past weekend.

    But right at the moment I have kids that are 4 and 7, and a wife who is a busy lgal doing things in the evenings after dinner usually at least 2 evenings a week.

    I try to only do darkroom sessions on nights that she is out, because otherwise with getting kids run around, and us both off working during the day at slightly different times, we would never really see each other.

    Working in tubes keeps you tied to the process, so the ability to interact with the kids is limited. So I would usually get the chems warming, the paper out of the fridge or freezer, and then get the kids to bed. I would hit the darkroom in ernest at around 9pm, and then print til the wee hours, since once you have your color under control you do not want to stop. Getting up for work was always a challenge the next day.

    In the spring I saw a 12" wide capable small fujimoto CP-31 tabletop roller transport for sale on criagslist for $300, including the wash dry module. It was in middling shape, but well made, and went for $6000 or more 10 years ago. So I bought it. The metal parts are all stainless steel, the drive gears all nylon; in short the thing is well made.

    Two of its three tanks needed cleaning big time. It seemed the thing had at one time ran EP2 (remember the tar?), and had not been rinsed after being last drained. Lots of runs with dilute toilet cleaner later, and scrubbing with a tooth brush and scotchbrite pads, on every conceivable surface and the thing is looking ok.

    Running it with about 20 partially fogged pieces of 11x14 B&W RC paper in lieu of buying expensive clean out sheets got all the last of the gunks off of the rollers. The rollers are all in good shape, because otherwise they would have been a deal breakers, owing to their replacement cost.

    The first tank temperature controller was a fancy digital model that had gone flaky. I changed out all of the electrolytic capacitors, and put a new nicad battery on the PCB, all for naught. It was beyond troubleshooting it back to health. It still blinks the temperature, but doesn't drive the heater. So I figured out the control wiring and thought a bit.

    *Bay for about $40 yielded 5 digital termostats that had been prototyped to control fan off time in a furnace. I changed the hysteresis resistor setting in the circuit of one unit to give a smaller swing between on and off. I then stuck the unit's thermistor probe into the hole where the replenisher hose usually goes near the pump inlet, and it tested well. The power supply this digital thermostat needed came from a salvaged laptop supply, after the laptop was long ago dead. Until I find a replenisher module for this thing I am using the arrangment as is.

    A number of the titanium tension springs that hold the rollers together were falling apart from stress cracking and corrosion. The previous used had replaced some with now crunchy ordinary rubber bands. I replaced these with square rubber drive belts from the electronics store. These come in various sizes, and lengths. Trial and error showed that 25mm is just the right length to squeeze, but not reject a piece of paper.

    So then I had this unit working on my workshop bench.

    I proceeded to build a rolling cart to put the unit at countertop height. There is a shelf to hold the roller tubes and motor base that I haven't tossed yet, and below that a bottom layer that holds the jugs that catch the overflow from the three tanks of the roller transport.

    I plumbed up a new water supply to feed the wash module low flow, but tempered water, and rejigged a drain inlet to catch the wash overflow. I also installed a dedicated GFI circuit to power the thing so everything else in the darkroom doesn't dim when the dryer heater first kicks in.

    I tried running the thing on home mixed chemistry that I use for tubes, but its developer formulation is not suited for the oxidization that the rollers accelerate, and its activity, as well as that of the blix required an 80 second per tank transport speed. Total cycle time was 7.5 minutes dry to dry.

    So I finally bit the biscuit and bought a batch of RA-RT by Kodak from Mondrian Hall, one of Canada's bigger photo supply wholesalers. Their counter sale prices were very competitive to that the biggy B&H charge in their store, if only they would ship the stuff. The down side is that Mondrian won't break up cases. So I now have 40l (4X10l) worth of Blix ( which should last a while, since it is stabilized from sulfating out) and 20l (4x5l;worth of RA-RT developer replenisher. The Fujimoto uses 2L per tank. The chemistry is supposed to be good if stored in bottles for at least 6 weeks.

    I mixed up the partial volumes to get the replenisher developer solution, and blix working/replenisher solution.

    I then MSDS web searched what was in Kodak RA starter. I then compared it to a 1L bottle of Champion RA starter that was picked off of the free shelf at the hazardous waste depot the last time I dropped of my dehydrated used fixer sludge and used bleach ( I also found a big lot of stable parts of E-6 chems). It looked compatible. Champion is now actually running the Kodak chem plants, so I knew they were a reputable supplier, and there were no components in the MSDS that were organic and subject to break down. So I mixed the developer working solution using the replenisher strength mix, more water, and the salvaged starter.

    The Fujimoto CP-31's bigger cousin, the CP-51 has only two tanks. So I have set the first tank on my three thank unit as a water wash to get rid of the dye coating off of the paper that I have learned in past roller tube work what Dr. Robert Chapman calls the big green meanies. I run this tank at about 30C so that the paper is not too soft when it hits the developer. At the end of a nights printing I dump this tank, and boy, is it blue. By keeping it out of the developer, I hope to help the developer last longer.

    The second tank is the working solution developer at 35C. The third tank is blix at 35C. Transport speed is set for 45sec per tank. Dry to dry is yields 4x5 test prints in 4.5 minutes, and larger prints only a bit longer than that.

    Last night was its first run on the new chemisty. Using my colorstar analyser, and standard test negative, I was into a stable color setup after only 2 test prints. Then I was away to the races. One print would go into the machine, the cover closed, and then I would go on to noting what its exposure parameters were, then on to exposing the next print. I note the exposure parameters in case I want to tweak something on a reprint.

    I stack prints as they come out of the dryer, and when the equivalent to two 8x10's had accumulated I replenish the developer and blix tank solutions. To do this I partially shift the cover to the side when there are no prints running, and at the edge of the tank opposite the drain I pour in 20ml per 8x10 of developer, and 20ml per 8x10 of blix using separate small cough medicine cups marked to the proper level. With time if I can find the correct replenisher module, or make one myself, I will, but for now this works.

    I could do the early part of the printing session while the kids were still up. I would pop into the darkroom, pick a neg, set it up, analyse it, expose, stick it in the processor, and set an old gralab 300 timer to buzz after 5 minutes. All the lego got picked up, the popcorn on the floor vaccuumed away, their teeth brushed, and stories read, and in that process, more than 8 prints were completed.

    By the time I was pouring the dev and blix back into storage bottles, rinsing the rollers, and rinsing the tanks at midnight I had been at it intermittently for 6 hours, and had cranked out 46 prints. Since a lot of them were ones with people in them, and my analysers skin tone settign is right on, there was no more than 3 prints all night that needed reprinting to tweak exposure or color cast.

    I never have done this much color with tubes. What a joy. All the fix up and setup work has now paid off after only one session in my eyes.

  2. #2
    Michel Hardy-Vallée's Avatar
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    Wow! You've got quite a story here, Mike. I just started processing RA-4 in tubes, and I can understand how a processor becomes necessary for any higher yield.

    For the same duration as your sessions, I can only get about 4 new proper prints. I spend up to three sheets for exposure and color balance, but the drum's fill-dump-repeat procedure takes time. At least I keep a consistent exposure record, otherwise I'd shoot myself!
    Using film since before it was hip.


    "One of the most singular characters of the hyposulphites, is the property their solutions possess of dissolving muriate of silver and retaining it in considerable quantity in permanent solution" — Sir John Frederick William Herschel, "On the Hyposulphurous Acid and its Compounds." The Edinburgh Philosophical Journal, Vol. 1 (8 Jan. 1819): 8-29. p. 11

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  3. #3
    AgX
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    You relly enjoyed that enterprise.

    But,
    Quote Originally Posted by Mike Wilde View Post
    So I have set the first tank on my three thank unit as a water wash to get rid of the dye coating off of the paper that I have learned in past roller tube work what Dr. Robert Chapman calls the big green meanies.
    what is this dye coating?


    And this free stuff shelf at the hazmat station is to drop surplus chemistry? But how will you know is has not been hampered with?

  4. #4
    Mike Wilde's Avatar
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    dye layer of RA-4 paper

    I'm not sure what exactly it does. I surmise it corrects the spectral response of the paper to deal with any batch to batch inconsistencies in the base paper, bui I have never heard exactly what it does.

    I know that if you are procesing in tubes, you pre-wet to warm up the paper in the tube, and a whole whack of blue dyed water comes out when you dump the tube.

    The starter came in a full bottle with a foam seal under the lid that had not been tampered with when I got the product.



 

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