From: Ken Watson (watsok@frii.com)
Date: 11/08/02-02:23:38 PM Z
Richard,
As an idea for the "softish" pad, today we might use polyurethane ( I think
this is the material ) . The same stuff used in skateboard wheels, and some
automotive aftermarket bushings for the suspension. It compresses but will
always spring back.
It is also use in the Jewelry industry for pressing 3 D ornaments out of
silver or at least used to form them. So silver foil would work but maybe
more expensive.
If anyone is interested try searching for Hydraulic Die Forming for
Jewelers and Silversmiths. This is a book that I have and I am sure there
is more than one web site on this.. They talk about a 20 ton press forming
4 x 6 inch sheets. They are also going for a lot more depth / relief that
something we would use for printing.
They actually make die's from epoxy that survive the pressure. I had thrown
this out quite a number of months ago, but since I am carbon challenged, I
do not have any way to test out casting a carbon image to see if there is
enough relief afterwards to make a die from epoxy or casting silicon. So if
anyone is looking for a new print medium here is the epoxytype. Actually,
Wayde gave me a print to try out but... I needed more mold release as his
print now has a dense coating of epoxy on it.
----- Original Message -----
From: "Richard Sullivan" <richsul@earthlink.net>
To: <alt-photo-process-l@skyway.usask.ca>
Sent: Friday, November 08, 2002 8:22 AM
Subject: Re: Woodburytypes
> I would explore the Stannotype process developed at the very end of the
> Woodbury life span. As we can see from the posted thread in the archives,
> a print smaller than 4 x 5 used 50 tons of pressure and that may not have
> been enough. Even 50 tons translates into 2000 tons for a 16 x 20. You'll
> need a press that can squish a greyhound bus to do that!
>
> The Stannotype used tin foil (stannous = tin) This is real tin foil and
not
> aluminium foil as us old folks continue to misname it. Real tin foil is
> hard to find. One source I found was in the hobby area of folks who
> reproduce Edison's original sound recordings which used real tin foil.
(And
> we thought we were retro!)
>
> Instead of pressing down the thick sheet of lead as in the Woodbury, the
> Stannotype used thin tin foil which was pressed down under a softish pad
> and far less pressure was needed. The relief was then backed up by casting
> of plaster behind it to give it support. From all reports at the time it
> was just as good at reproducing an image as the Woodbury but since other
> reproduction methods came along it and the Wooodbury were quickly
abandoned.
>
> The Woodbury's claim to fame was in being able to Make a number of images
> for tipping into books. I have several books in my collection with tipped
> in Woodburys. The trick was you could make a small 2 x 3 inch portrait
cast
> it in lead and make say 20 more casts from the same gelatin relief. The 20
> lead casts were soldered up and the 20 prints were then pulled by filling
> with the colored gelatin and pressing it under a light pressure.
>
> I have seen claims that they don't hold "detail". Bull pucky! This might
be
> true under microscopic examination and I think a 16 x 20 inch Woodbury
> would be spectacular. Pulling an edition once the plate was made would be
> fairly easy and you could literally pull an unlimited amount.
>
>
> --Dick Sullivan
>
>
>
>
> At 09:45 AM 11/8/2002 +0100, you wrote:
> >Hi Craig,
> >
> >Jan van Dijk used to be on this list (Hello Jan are you still there?). He
> >teaches and publishes about historical photographic techniques and is an
> >expert in photo determination.
> >
> >There is a 1999 post about their Woodburytpe research in the archives:
> >
> >/lists/alt-photo-process/1999/alt99a/2462.html
> >
> >
> >Kees
>
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