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Re: Gum vs. Kallitype
>1. Rives BFK or Fabriano Artistico is shrunk, sized, and hardened in
>glyoxal.
>2. Anywhere from 1 to 7 coats of gum are applied.
>3. Kallitype layer is applied and developed in Sodium Acetate.
>4. Cleared in mixture of hypo and EDTA
>5. 1 minute swish in Heico Permawash
>6. Washed in cold water.
>
>At step six, the gum is starting to flow off of the paper. I'm thinking
>that the Permawash might be the culprit ...
Permawash, I take it, is a washaid. Washaids usually contain soda. Soda
attacks gelatine. With standard silver prints this is not much of a
problem as the gelatine is fairly tough and will survive a minute or two
(but try 5 or even 10 minutes!). Glyoxal, however is not a very effective
hardener. My advice: Clear the gum print in alun (may take 30 minutes or
more) -- this will further harden the gelatine. Then let it rest for a
couple of days. Omit step 5 and extend step 6.
Andre