I usually put down the first of three layers in a
tri-color without size. Then after that I brush on PVA 1:2. It's fine for the
next 2 coats. No stain...even when the third coat is blue.
Sorry to hear about what U of S did to your
position. This list has been an incredible resource for getting re-immersed in
gum. Don't picture that!
Inspired by the discussion of alternatives to
gelatin sizing I have incorporated Golden's PVA size into a one color (and
multi-color) assignment for my alt photo I class.
My question is: Has
anyone done test to determine if PVA sizing is needed for each layer (coat /
exposure) of gum? I was under the impression that because of the dilution
(1:2) or because it is water based that long soaks in water would strip away
enough of the PVA to allow staining to occur. After observing how
stubborn PVA adheres to the plexiglass I am coating on, I am wondering if
extra coats are needed.
I am just foam brushing on the PVA size, 1:2,
onto BFK Rives.