Re: Gum print formaline

Katharine Thayer wrote:
>
> Ryuji Suzuki wrote:
> >
>
> >
> > When someone brought up gesso last time I tried it, but it was too
> > gritty and I didn't like it.
>
> Gesso mixed with gelatin, in my experience, is not gritty at all, but
> perfectly smooth; Arches Bright White hot press sized this way, for
> example, is actually perceptibly smoother to the touch than the
> unsized paper, which is quite smooth in its own right. The sizing adds a
> velvety quality that's not there in the original paper, and not a speck
> of grittiness. I suppose if a very high proportion of gesso were used,
> then you'd get a grittier surface, but my experience is that a high
> gesso to gelatin ratio won't hold gum anyway, so wouldn't be a ratio
> that you could use functionally.
>
> Yes, Kate, it's acrylic gesso, and I don't dilute it before mixing it
> with the gelatin. About 1/3 gesso to gelatin solution works well for me.

Sorry, that's wrong; I just tossed that off the top of my head without
thinking about actual amounts. Here's the real numbers: What works well
for me is 30-50 ml of the gesso in 200 ml of 3.5% gelatin, which is more
like 1/4 or 1/5 than 1/3.

And I should add that I don't know for a fact that gesso mixed with
gelatin at a higher proportion results in a gritty surface; I was just
trying to reconcile Ryuji's observation that he found it gritty with my
own experience that it's not, by speculating that perhaps he mixed it at
a higher ratio of gesso to gelatin than I do. But the times when I did
find that I was getting too much gesso in the mix (1/2 or more) and the
gum wouldn't stick, I didn't notice any grittiness in the sizing.
kt
Received on Thu Feb 3 15:45:44 2005