Re: polymer plate drying time
Jon and Keith,
Thanks for this discussion. Lots of helpful information.
I rigged a striplight under my exposure head so that now I can really
watch the positive as it gets sucked down against the plate. What I
see are lots of little irregular shaped areas that move and change
shape, and they're colors are rainbow-like and change... I think it's
a Newton's rings kind of thing. (and no I haven't been smoking
anything :P ) The shapes are larger in the beginning, then get
smaller but more numerous as the vacuum continues. This is SO hard to
describe, haha. Do you all see anything like that happening?
I'm snowed in here and happy as a clam to be heading to my studio for
a day of printing! Will definitely be drying my OHP now. I'm going
to find one of those bonnet hairdryers this week and try out using it
to rig a drying box.
Happy St Patrick's Day!!!
Susan O'Flaherty O'Daly (my real family names 2 generations back :o) )
On 3/17/07, Jon Lybrook <email@example.com> wrote:
More questions and responses below...
Keith Taylor wrote:
> I remove the Mylar and dust with talc (screen and positive).
Do you use actual talc, or baby powder? I've found that real talcum
powder is difficult to find - though I used some in Florence. Much more
chalky and coarse than baby powder -- at least the batch I had access to.
> I have a 33x43" vacuum frame with glass, get 22in Hg and I leave it
> for at least 3 minutes before exposure. I have a ribbed bed to the
> frame which causes problems with platinum prints, so I have a sheet of
> black plastic 1/32" thick.
The Kreene makes it so I can only get about 12 in the vacuum frame.
Images are generally pretty sharp except for the patches though.
> You use an anti-static spray regularly don't you?
Yes, due to the Kreene plastic.
> I clean the glass with a non-ammonia, non-alcohol based cleaner, but
> no anti-static spray. I also use Pictorico on a roll (never sheets)
> with an Epson 4000. I do have a 2200 that I use infrequently with
> sheet Pictorico, but not for gravure - usually small platinums.
> I dry the OHP in the film drying cabinet for 20-30mins low heat prior
> to use.
Drying the OHP seems to be the biggest difference, since I used to have
glass in my vacuum frame, and do basically everything similarly to
you....but I've never bothered to try drying the OHP with heat for 20-30
minutes. I did use to dry my plates with a hair drier until I was told
by an instructor that it was a waste of electricity...NOT.
> I'm just throwing out things here that you may recognise as being
> different from your setup.
Thanks Keith. I'm very eager to dry some OHP and try dusting again,
both the plate and positive and will report back.
gravure blog at www.susanvossgravures.blogspot.com