----- Original Message ----- From: Butch Black Subject: OT: RA-4 Chemistry question
> Hi Gang; > > I've got a real stumper for all you fellow lab rats. Our printer, an Agfa > MSC 300 won't stay in control. We have jacked up the developer replenishment > rate from 120ml to 280ml, increased the developer temp from 38C to 40C. Our > LD continues to fall and with the increase in temp our D-MAX has dropped > significantly to borderline out of control (-10 to -15). The tank temps are > within .2c and we just replaced the circulation pump (cured a temp > fluctuation problem we had). We are dumping 5L of tank solution and > replacing it with replenisher 1-2X a week to keep it close to control. Lets see, you have more than doubled your replenishment rate, and have bumped your temp, and your just barely in control. Have you actually measured the pump output on the developer pump? Are you sure the replenisher is mixed correctly? Are you sure the correct chemistry is being used? A hint with RA-4 chemistry. The CD consists of a developer and a restrainer. The restrainer is more susceptible to dilution. Adding water will increase the developer activity. Adding raw replenisher will retard the developer activity. William Robb > > My best guess is weak developer replenisher. My problem is that there are > certain subjects that are not allowed to be broached in my shop, chemistry > being one of them ( I work for all the screwballs I guess) so If my > suspicions are correct I won't be able to do anything about it anyway. If > anyone has any ideas let me know. Also, if anyone has Aaron's lab e-mail > could they please forward this e-mail to him as he has a wealth of knowledge > in these matters. > > A little history. When I started to work at the lab I'm now in there were 2 > months of control strips that had been run but not read and all 3 machines > were out of control. Recently, the owner decided that too much time was > being spent on control strips (15 min), so he has taken over the job, and I > haven't seen a plot since, though he does run and read strips occasionally. > > BUTCH > > "Each man had only one genuine vocation - to find the way to himself" > Hermann Hesse (Demian) > >
