View Full Version : Mixing Pyrocat-HD

Peter Witkop
24-Jan-2004, 20:13
My first batch of pyrocat produced some great results, no problems using it in my cpe2 with it's single, rather fast 75 rpm speed. I went to mix my second batch the other day, and had trouble getting solution b to dissolve. It gets to a milky mixture, which eventually settles out. I mixed solution B at room temp, which IIRC was what the instructions called for (I don't have them handy, I got the kit from photographers formulary), and mixed with distilled water in clean containers. I was wondering what I might have done wrong, and any advice anyone might have? Thanks :o)


Michael Kadillak
24-Jan-2004, 20:51
During my first trials with this developer I had problems getting my B solution from Photographers Formulary to go into solution as well even though I used a hot plate magnetic stirrer. My solution was to order the bulk chemicals and mix my own. As Sandy King said recently, since you are not near the critical saturation levels at the prescribed dilutions for the B solution (the chemical reaction of putting it into solution even produces a modest amount of its own heat), it should not be a problem. Everything else you did right - distilled water in clean containers. Since Pyrocat is without question the cheapest and most universal pyro I have ever used, I think that you would be best served by purchasing your own chemicals bulk and mix your own. Many vendors sell reasonable quantities if you are still in the trial stage in your work. One of my other mistakes with using this developer was to not use separate pipets for the A and B solution as it is extremely easy to contaminate the stock solutions which can be a real problem. Good Luck!

Frank Lahorgue
24-Jan-2004, 23:10
I've just begun to use p-cat HD purchased from Photographers Formulary as well. Rather than using a pipette, I store the A and B solutions in cleaned out A1 sauce bottles. The solutions pour very slowly from these bottles making it easy to measure in a 10 ml beaker and avoiding the problem of contamination using pipettes.

I haven't yet finished my testing, but so far I am very impressed with results I am getting using BTZS tubes.

Thanks for sharing information.

Jim Chinn
25-Jan-2004, 08:41
You need to increase the temp of the distilled water for mixing. I have been buying the chemicals in bulk for awhile, but believe photo formulary states 125F in the instructions. I find at 100F I have no problem mixing either solution. For mixing the solutions together I use a couple of syringes, one marked for each solution.

Peter Witkop
26-Jan-2004, 16:46
Thanks for all the responses, I think I'll just mix some new solution B hoping it works out better, and be rid of the old one.