Re: A PVA for printing "gum" : a practical approach

In a message dated 30/3/06 12:26:52 am, jseigel@panix.com writes:

> now I surmise from this citation that 14 baume gum is (still)
> the criterion.  That's a substance I buy by the gallon -- now somewhat up
> in price, it seems, but last time my favorite was just $16.  (About 8
> British pounds, I gather.) Can someone explain why that's not good enough?
>

One's preference for a particulat specific gravity depends upon one's working
methods and the style of the final print.

I started with a heavier gum and found that the printers' 14 gum was too thin
for me. I tried a gallon of the printers' 14 but passed it on to someone else
  even before I discovered Gloy all those years ago. I prefer the 17 but
that does not make the 14 wrong.

The result is that when I mix up PVA and glycerine for my gum prints I aim to
achieve the same consistency as that of Gloy or the gum I preferred, but that
is my choice.

Is it possible that anyone, as a result of all this experimentastion, can
say which of the PVAs in the catalogues is the one best suited to our purpose
of making gum prints and what the criteria were that led to that choice.

Or does it , as in our experience, not seem to matter very much ?

Terry

In practice, dichromated gum works in much the same way as dichromated, but
plasticised PVA..
Received on Wed Mar 29 22:58:24 2006